Norms for the installation of septic tanks and permits. Snip and sanpin for autonomous sewers
There are two groups normative documents regulating the requirements for treatment facilities. The first group includes building codes - SNiPs. They determine how the wastewater treatment plant should be designed and built. The second group includes documents containing sanitary and hygienic standards and requirements for water disposal - SanPiNs. They, in turn, are controlled.
The main document that guides the construction treatment facilities, - SNiP 2.04.03-85 “Sewerage. External networks and structures”. In particular, it establishes a very important parameter - the size of the sanitary protection zone, that is, the minimum allowable distance from the treatment plant to residential development.
At its core, this SNiP has not been revised since 1985. As you know, in the USSR there were no local treatment facilities of low productivity, designed for individual users, except for cesspools, so the minimum volume of wastewater considered in this document is 200 cubic meters per day. About a thousand people can produce that much. Therefore, in the current regulations there is a "white spot" just for local treatment facilities of low productivity.
Another fundamental document of federal significance is SNiP 2.04.01-85 * "Internal water supply and sewerage of buildings." In it, in addition to calculation methods and rules for the construction of sewerage networks inside buildings, water consumption rates for various consumers are given. But this is the most important parameter when calculating the required performance of treatment facilities.
Some regions have their own guidelines for water use and sanitation. In the Moscow Region, these are the territorial and construction standards for water supply and sanitation systems for residential low-rise buildings in the Moscow Region TSN ViV-97 MO, TSN 40-301-97.
This document is somewhat more up-to-date than the indicated SNiPs, and contains more detailed information on local treatment facilities of low productivity. Here are some of the most important extracts:
“Intensive development in the suburbs of cottage construction, farming and small subsidiary plots, low-rise residential settlements that do not have treatment facilities, has a negative impact on the state of groundwater and surface water. This is due to the specifics of water use in individual residential buildings, when the water intake structure of the water supply system is located in close proximity to the drainage system. This kind of use of water bodies is contrary to Art. 133 and Art. 144 of the Water Code Russian Federation and SanPiN 2.1.4.1110-02 in terms of creating reliable sanitary protection zones for water intake facilities and prohibiting the discharge of wastewater into water bodies within the sanitary protection zone and district.
These territorial building codes establish a general procedure for the design, construction and reconstruction of drinking water supply and domestic wastewater systems in low-rise residential areas of the Moscow Region, the production and installation of drinking and waste water treatment plants. Low-rise residential buildings include:
- individual houses and farms, personal subsidiary plots;
- detached 3-4-storey houses, groups of cottages;
- settlements with up to 5,000 inhabitants (including cottage and summer cottages).
Sanitary protection zones of treatment facilities for wastewater disposal systems of low-rise residential buildings, depending on the productivity and type of facilities in accordance with SNiP 2.04.03-85, must be taken:
- 15 m for underground filtration fields, with a capacity of up to 15 m3/day;
- for filter trenches and sand and gravel filters with performance:
- 1 m 3 / day - 8 m,
- 2 m 3 / day - 10 m,
- 4 m 3 / day - 15 m,
- 8 m 3 / day - 20 m,
- 15 m 3 / day - 25 m;
- 5 and 8 m for septic tanks and filter wells, respectively;
- 100 m for biofiltration facilities, with a capacity of up to 50 m 3 / day.
- 150 m for biological treatment facilities with a capacity of up to 200 m 3 / day. with drying of the stabilized sludge for silt pads;
- 50 m for aeration installations on complete oxidation, with a capacity of up to 700 m 3 / day.
For individual and local wastewater systems, if it is impossible to comply with the regulatory sanitary protection zones, the placement of treatment plants must be agreed with local supervisory authorities.
As for sanitary-hygienic and environmental standards, it is necessary to make a remark: today there are a lot of documents that partially contradict each other. In particular, this concerns the definition of sanitary protection zones for wastewater treatment plants of low productivity.
Note that in fact we can talk about two different zones: the first is the distance from the treatment plant to residential buildings, the second is from the point of discharge of treated water (drainage) to sources of underground and surface water supply and water use. SanPiNs regulate both the first and the second.
The main document that guides the regulatory authorities and the creators of treatment facilities is SanPiN 2.1.5.980-00 “Hygienic requirements for the protection of surface waters” from the section “Water disposal of populated areas, sanitary protection of water bodies”, adopted in 2000. All hygienic and ecological conclusions and certificates are issued on its basis. It establishes hygienic requirements "for the placement, design, construction, reconstruction and operation of economic and other facilities that can affect the state of surface waters, as well as requirements for organizing control over the quality of water in water bodies."
Also, the main document is - SanPiN 2.2.1 / 2.1.1.1200-03 "Sanitary and epidemiological rules and regulations" from the section "Sanitary protection zones and sanitary classification of enterprises, structures and other objects", adopted in 2003. As the name implies, it determines the size of the sanitary protection zones depending on the classes of objects. Despite the relative novelty, it still has the same very significant size of the sanitary protection zone from treatment facilities to residential areas for stations. closed type- 50 meters.
An important hygienic and anti-epidemic task is the cleaning of populated areas from waste generated in the process of production, household activities of a person.
Distinguish between liquid waste (sewage, water from cooking, washing dishes, washing, wastewater from industrial and commercial enterprises) and solid waste (garbage, food leftovers, household waste, etc.). Waste can contain pathogens of infectious diseases and pollute the soil and water with them, serve as a breeding ground for flies.
The most hygienically preferred liquid waste disposal system is sewerage. Sewerage is a rafting system in which sewage diluted with water is rafted through pipelines outside settlements. Sewerage is built only if there is a water supply. With a combined sewerage system, atmospheric (rain, melt) water is also discharged through pipelines along with domestic and industrial water. With a separate system, wastewater enters the treatment plant, and precipitation is removed through the rain network directly into the reservoir.
For businesses Catering best solution sewage disposal is the connection to the centralized city sewerage. At the same time, the company is designing separate internal networks of domestic and industrial sewerage to prevent domestic wastewater from entering the technological equipment. sewer risers with household drains, it is not allowed to lay in commercial, industrial and warehouse premises; when located in ceilings, they are sealed.
Technological equipment is attached to sewer network with a jet break from the top of the receiving funnel 20 mm. At large enterprises for the treatment of industrial wastewater (before it enters outdoor network) from fats, starch, pulp, sand and dirt at the outlet from the respective shops (meat, fish, vegetable shops and washing) are installed outside the building of the facility for partial mechanical cleaning. Sewer drains are installed in the floors of production workshops and washing facilities.
In non-sewered areas, it is allowed to place public catering establishments with a number of places not exceeding 25. The wastewater of such an enterprise enters a concrete pit, and a water seal is installed on the drain from the production premises. The concrete pit should be at least 25 m away from the production premises.
The removal of liquid waste in the absence of sewerage is carried out by sewage transport.
All wastewater must be delivered to treatment facilities, where, in addition to cleaning, they are disinfected.
Solid waste (garbage) is collected in metal containers (80-100 l) with lids, installed on a special asphalt (concrete) site. Food waste is collected separately from garbage in special tanks (12-15 l) with lids in production facilities, where they can be stored for no more than 4-7 hours. Then they are stored at a temperature of 2 ° C in a food waste chamber. Waste removal is carried out daily in summer, in winter - every other day.
Garbage bins can be concrete, upholstered with iron. They should be cleaned when they are no more than two-thirds full and disinfected with a 10% bleach solution.
Sanitary regulations
device and operation of household and fecal sewerage
(approved by the Deputy Chief State Sanitary Doctor of the USSR on December 6, 1963 No. 459-63)
. General provisions
1. These sanitary rules apply to the design of new construction, reconstruction and operation of internal and external networks of domestic and fecal sewerage of residential and public buildings, industrial and auxiliary buildings of industrial enterprises, as well as facilities for the treatment of domestic and fecal wastewater from populated areas, industrial enterprises and stand-alone buildings.
At existing facilities, the requirements of these rules must be met within the time agreed with the local authorities of the sanitary and epidemiological service.
2. The conditions for the disposal of wastewater and the determination of the necessary treatment before release into water bodies must comply with the requirements of the Rules for the Protection of Surface Water from Pollution by Wastewater (No. 372-61).
The question of the joint disposal of domestic fecal and industrial wastewater should be resolved in each individual case, based on the composition of the latter and specific sanitary conditions.
3. Technical solutions in the design and construction of household and fecal sewage facilities must comply with the requirements of building codes and regulations approved by the State Committee for Construction of the USSR. (SNiP II-G. 6-62 "Sewerage. Design standards", SNiP II-G. 4-62 "Internal sewerage of residential and public buildings. Design standards", SNiP II-G. 5-62 "Internal sewerage of industrial and auxiliary buildings of industrial enterprises. Design standards").
4. The conditions for the disposal of wastewater, the degree of their purification and the place of discharge into the reservoir in the process of allocating a site for construction, as well as before approving projects for the construction or reconstruction of a domestic fecal sewage system, must be agreed with the state sanitary supervision authorities.
5. Sewage can be sewered through separate, incomplete separate, general alloy and combined systems, and with special requirements regarding the discharge of polluted rainwater into intracity water bodies - through a semi-separate system.
The choice of system should be made on the basis of a comparison of the technical, economic and sanitary-hygienic indicators of the options.
6. Water from stationary snow melters, after passing through a sand trap, may be discharged into any sewer network (rain, general alloy, domestic).
7. The release of rainwater is not allowed:
a) in stagnant ponds;
b) in eroded ravines (if it is inexpedient to take measures to strengthen them);
c) in closed hollows and lowlands prone to swamping;
d) to water bodies - in places specially designated for beaches;
e) in fish ponds - without special agreement.
8. In the absence of reservoirs for the discharge of rainwater and with appropriate climatic conditions in agreement with the local bodies of the sanitary and epidemiological service, evaporation sites can be designed.
9. The release of industrial wastewater into the city sewer is allowed only in cases where this does not disrupt the operation of the network and treatment facilities of the city sewer.
10. Industrial wastewater that may contain dangerous bacterial contamination (anthrax, glanders, etc.) must be disinfected before being discharged into the city sewer.
11. The conditions for receiving contaminated industrial wastewater into the sewerage of populated areas and the degree of their preliminary treatment, if any, must be agreed with the bodies of local Soviets of Workers' Deputies and local bodies of the sanitary and epidemiological service.
12. When choosing a wastewater treatment method and the location of treatment facilities, the possibility and expediency of biological wastewater treatment in natural conditions should be identified first of all.
If there is a possibility and expediency of agricultural use of wastewater, the latter can be applied in compliance with the sanitary requirements set forth in the Sanitary Rules for the Construction and Operation of Agricultural Irrigation Fields for the Neutralization and Use of Wastewater.
Artificial biological treatment can be applied in cases where natural biological treatment cannot be applied due to local conditions, sanitary requirements or technical and economic considerations.
13. The design solution for wastewater treatment should take into account the prospective development of the settlement in accordance with the general design of its planning and development.
14. The norms adopted in the project for the disposal of domestic and fecal wastewater must comply with the norms of water consumption approved by the State Committee for Construction of the USSR and given in the Sanitary Rules for the Design, Construction and Operation of Domestic and Drinking Water Pipelines.
15. The dimensions of the sanitary protection zones (gaps) between sewerage treatment plants and residential areas or food enterprises should be taken based on the data indicated in Table No. 1.
Table 1
Dimensions of sanitary protection zones
Wastewater treatment facilities |
Distance in meters at the estimated performance of treatment facilities in thousand m 3 / day |
||
more than 0.2 up to 5 |
more than 5 to 50 |
more than 50 to 500 |
|
1. Structures for mechanical treatment with sludge beds for digested sludge |
|||
2. Structures of artificial biological treatment with sludge beds for digested sludge |
|||
3. Filter fields |
1000 |
||
4. Irrigation fields |
1000 |
Notes:
1. Sanitary protection zones (breaks) for treatment facilities with a capacity of more than 500 thousand m 3 / day are established in agreement with the bodies of the sanitary and epidemiological service.
2. When the facilities for drying sludge are located in enclosed spaces, as well as in the absence of sludge sites on the territory of the treatment plant, the gaps established in clauses 1 and 2 of the table are reduced by 30%.
3. For sludge sites located outside the treatment plant, breaks should be installed, as for a treatment plant with mechanical cleaning, according to its capacity.
4. The distances given in the table should be calculated from the buildings of residential quarters and buildings of food enterprises to the boundaries of the territory of the treatment facilities, taking into account the prospective expansion of the latter.
5. Sanitary protection zones (breaks) can be increased at the request of the sanitary and epidemiological service, but not more than twice, in the case of residential areas located on the leeward side of the treatment plant.
6. When drying raw (non-fermented) sludge on sludge beds, sanitary protection zones (breaks) are established in agreement with the local bodies of the sanitary and epidemiological service.
16. The dimensions of the sanitary protection zones (gaps) for small sewage treatment plants (with a capacity of up to 200 m 3 / day) should be taken based on the data indicated in Table No. 2.
table 2
Dimensions of sanitary protection zones (breaks)
Structure types |
Distance in meters from residential buildings |
1. Fields of underground filtration throughput up to 15 m 3 / day of wastewater |
|
2. Irrigation fields of communal type with an area of up to 1 ha |
|
3. Irrigation fields of communal type with an area of more than 1 ha |
|
4. Filtration fields up to 0.5 ha |
|
5. Filtration fields with an area of more than 0.5 ha |
|
6. Structures for mechanical and artificial biological treatment (with sludge beds) with a capacity of up to 50 m 3 / day |
|
7. The same, with a capacity of more than 50 m 3 / day |
|
8. Biological ponds |
Note:
When arranging closed sludge areas, the distance according to pos. 6 and 7 can be halved.
17. Treatment facilities should be located, as a rule, in relation to the nearest residential building or group of buildings on the leeward side of the prevailing wind direction during the warm season (according to the average wind rose based on long-term observations), as well as downstream of the river and groundwater from water intake structures fed by these waters.
18. Sanitary gaps from the buildings of pumping stations located within the urban area to the buildings of residential areas or food enterprises should be taken:
a) with the estimated productivity of the station up to 50 thousand m 3 / day - 20 m;
b) the same, more than 50 thousand m 3 / day - 30 m.
19. For personnel servicing sewer facilities, appropriate measures and devices should be provided to ensure labor protection.
II. Sanitary requirements for the arrangement of internal household and fecal sewerage of residential and public buildings, industrial and auxiliary buildings of industrial enterprises
20. The arrangement of internal utility and fecal sewerage is mandatory in residential and public buildings, industrial and auxiliary buildings of industrial enterprises, in which the arrangement of internal utility and drinking water supply is provided.
Note:
In production and auxiliary buildings of industrial enterprises, it is allowed to install an integrated internal sewerage network for the removal of industrial and domestic fecal wastewater, provided that it is possible to treat them together or if there is an appropriate external sewerage system.
21. Residential and public buildings erected in canalized areas of populated areas must be equipped with internal sewerage. During the construction of buildings in non-sewered areas of populated areas, the following buildings should be equipped with internal sewerage with the installation of local treatment facilities:
a) residential buildings above 2 floors;
b) hotels, boarding houses and hostels (with the exception of class III hostels);
c) hospitals, maternity hospitals, polyclinics, outpatient clinics, dispensaries, sanitary and epidemiological stations;
d) sanatoriums, rest houses, pioneer camps;
Note:
It is allowed to build pioneer camps with a capacity of 240 seats or less for use only in the summer without a centralized sewage system.
e) kindergartens, boarding schools, educational institutions;
f) general education schools.
Note:
It is allowed to build schools with a capacity of 320 students or less in the presence of sanitary and feasibility studies without an internal sewage system.
g) theaters, clubs, cinemas.
Note:
It is allowed to build clubs and cinemas with auditoriums up to 400 seats inclusive without a device internal sewerage.
When designing these buildings for construction in the 1st climatic region, it is necessary to provide for the installation of backlash closets outside the main dimensions of the building, and in II, III and IV climatic regions - outdoor latrines.
h) catering establishments.
Note:
It is allowed not to equip public catering establishments with internal fecal sewage, instead of which, in climatic regions I, II and III, backlash closets should be arranged, and in climatic region IV - external latrines.
i) stadiums of 5,000 spectators and more;
j) communal baths and laundries.
22. Discharge sewer pipes from sanitary appliances are not allowed to be placed under the ceiling of residential premises, kitchens, hospital wards, doctors' offices, bedrooms, treatment rooms, dining and trading rooms, workrooms of administrative buildings, warehouses for food products and valuable goods, lobbies, premises with valuable decoration, meeting rooms and auditoriums, classrooms, classrooms, supply ventilation chambers and rooms requiring a special sanitary regime.
23. Sanitary appliances and sewage receivers connected to the domestic fecal sewer must be equipped with a hydraulic seal (siphon) located at the outlet under the appliance or in the design of the appliance itself.
24. Wastewater receivers must be provided with a flushing device from the water supply network.
25. All toilet bowls should be equipped with individual flush cisterns or flush taps.
26. Internal sewerage networks should be made of cast iron sewer or asbestos-cement non-pressure pipes. Use of plastic pipes is allowed.
Internal sewer networks can be laid openly with fastening to walls and ceilings or hidden in the structure of ceilings and under floors in the ground, in prefabricated blocks, panels, cabins, as well as in furrows and boxes with a device against revisions of inspection hatches with doors.
27. Networks of household and fecal sewerage, as well as industrial sewerage networks that discharge polluted wastewater that emit odors, must be ventilated through risers. In necessary cases, internal networks are equipped with special ventilation risers.
28. The connection of the exhaust part of the sewer risers with the ventilation systems of buildings and chimneys is prohibited.
29. The exhaust part of the sewer riser must be brought out 0.7 m above the roof of the building. The mouth of the exhaust pipe must be equipped with a wind vane. Exhaust risers leading above the roof must be at least 4 m away from opening windows and balconies, and with flat roofs, exhaust pipes must be led to a height of at least 3 m above the roof level.
30. A manhole must be provided at the point where the outlet is connected to the external sewer network.
Note:
The device of manholes on the network of fecal sewage inside the building is not allowed.
III. Sanitary requirements for the installation of external household and fecal sewerage in populated areas, industrial enterprises and detached buildings
a) Sewer networks
32. On the territory of populated areas and industrial enterprises, overground and ground laying of a sewer network is not allowed.
When crossing deep ravines and reservoirs, as well as when laying sewer pipes pipelines outside settlements, above-ground laying of pipelines (along overpasses and bridges) is allowed.
33. The design of open sewer channels for treated wastewater is allowed outside the territory of settlements, taking into account local conditions and with the permission of the sanitary and epidemiological service.
34. The location of sewer networks should ensure the safety of water lines from the ingress of sewage into the water supply network in case of damage and accidents on the sewer network.
35. When laying parallel sewer and water pipes, the clear distance from the sewer pipelines to the water lines must be at least:
a) when laying at the same level and with a diameter of water conduits up to 200 mm - 1.5 m;
b) with a diameter of 200 mm or more - 3 m;
c) when laying water pipelines below the sewer line, the indicated distances must be increased by the difference in the marks of the depths of the pipelines.
Note:
In cramped conditions, the distances indicated in this paragraph may be reduced with special justification and agreement with the organizations concerned.
36. Sewer pipelines at the intersection with utility and drinking water supply lines should be laid, as a rule, below the latter with a vertical clear distance of at least 0.4 m between the pipes.
When crossing at a vertical distance of less than 0.4 m or when laying sewer pipes above the water supply, protective measures must be taken (laying water supply from steel pipes, sewerage - from cast iron, as well as gasket water pipe in a protective case with a length of at least 5 m on each side of the intersection in clay soils and 10 m in filtering ones).
37. Sewer gravity pipelines can be made of ceramic, concrete, reinforced concrete and asbestos-cement blocks; in exceptional cases, the use of special bricks is allowed.
Sewer pressure pipelines must be made of reinforced concrete, asbestos-cement, cast iron and steel pipes.
38. Appropriate ventilation must be provided for the sewer network.
39. When crossing reservoirs, siphons should be laid in at least two working lines made of steel pipes with reinforced anti-corrosion insulation. Reserve (non-working lines) of siphons can be provided if there are special requirements justified by technical, economic and sanitary considerations.
Note:
When crossing ravines and dry valleys, and in justified cases, when crossing small reservoirs, with an insignificant flow of wastewater, it is allowed to lay a siphon in one line.
Gates must be provided in the inlet and outlet chambers of the siphon, as well as in the emergency outlet. The device of emergency releases is allowed in agreement with the local bodies of the sanitary and epidemiological service.
Emergency release closures must have sealing devices.
40. The locations of the heads of wastewater outlets must be agreed with the bodies of the sanitary and epidemiological service.
41. To regulate the flow of rainwater in order to reduce the diameter of the network pipes, existing ponds that are not sources of drinking water supply and are not used for swimming, sports and recreation of the population can be used. In the absence of this possibility, such ponds can be designed in the zone of green areas or closed reservoirs.
b) Pumping stations
42. Pumping stations for pumping wastewater should be located in separate buildings. Protective green spaces should be provided along the perimeter of the territory of pumping stations.
43. Emergency release of sewage with pumping station into reservoirs or into a rain network must have a sealing device.
44. The locations of pumping stations and emergency outlets must be agreed with the local bodies of the sanitary and epidemiological service.
45. The air temperature in the engine room and in the grate compartment with the constant presence of service personnel during the heating period should not be below plus 16 °. In summer, this temperature in the engine room should not exceed the outside air temperature by more than 5°.
46. The operation of pumping stations, as a rule, should be automated.
47. The receiving tanks and the room for gratings must be separated from the machine room by a deaf watertight partition.
48. Mechanized cleaning of screens from waste is mandatory if their quantity is 0.1 m 3 / day or more. When the amount of waste is less than 0.1 m 3 /day, gratings with manual cleaning are allowed.
49. At pumping stations with mechanized screens, it is necessary to provide for the installation of crushers for grinding waste, followed by feeding the crushed mass into waste water, as a rule, up to the screen. When the amount of waste is more than 1 t/day, in addition to the working one, it is necessary to provide for the installation of a backup crusher. With manual screens, the waste must be removed in closed containers.
50. In the premises of pumping stations, supply and exhaust ventilation should be provided:
a) for a receiving tank with five air changes per hour;
b) for the engine room when heat is released from the engines in an amount exceeding the heat loss of the room - according to the calculation, and in the absence of excess heat - with a single air exchange per hour.
Note:
In the premises of pumping stations with a capacity of up to 1000 m 3 / day, natural ventilation is allowed using deflectors or transoms.
51. As part of pumping stations, the following service, amenity and utility rooms should be provided:
Pumping station performance |
With manual pump control |
With automatic pump control |
||||
washroom with washbasin |
shower room |
office space (room) |
washroom with washbasin |
shower room |
||
up to 5000 m 3 / s |
for 1 toilet |
for 1 grid |
for 1 toilet |
|||
over 5000 to 15000 m3/s |
8 m 2 , besides a workshop, 10 m 2 pantry 6 m 2 |
for 1 toilet |
for 1 grid |
8 m2 |
for 1 toilet |
for 1 grid |
more than 15000 to 100000 m 3 / s |
12 m 2 besides a workshop, 15 m 2 pantry 6 m 2 , wardrobe |
for 1 toilet |
for 1 grid |
workshop room 20 m 2 |
for 1 toilet |
for 1 grid |
more than 100000 m 3 / s |
20 m 2 in addition workshop 25 m 2 , pantry 10 m 2 , wardrobe |
for 1 toilet |
for 1 grid |
52. Water supply to pumping stations should be provided, as a rule, from the network of domestic drinking water supply of a settlement or the nearest enterprise.
53. The performance of working pumps and power supply should ensure the uninterrupted operation of pumping stations.
c) Sewerage treatment facilities
54. The amount of domestic wastewater and the mode of their entry to treatment facilities should be established taking into account the prospective development of a populated area and water disposal standards.
55. A set of treatment facilities should be selected depending on the required degree of wastewater treatment, their composition, the capacity of the treatment plant and other local conditions.
56. The territory of the treatment facilities should be surrounded by a fence or hedge, landscaped, landscaped, illuminated and have paved roads and footpaths to each of the structures and buildings.
57. The design of the outlet into the reservoir should ensure the most efficient mixing of the purified liquid with the water of the reservoir.
58. Lattices as part of treatment facilities should be arranged both with gravity and with pressure flow of sewage to the treatment plant.
When the pumping station is located on the territory of the treatment plant or in its immediate vicinity, gratings are installed at the pumping station.
59. Transportation of waste from grates to crushers with more than 0.1 m 3 / day must be mechanized.
60. Crushed waste is allowed to be sent to waste water up to the grate, as well as pumped into digesters.
61. Supply and exhaust ventilation with a five-fold air exchange should be provided in the lattice building, and the exhaust must be carried out from the lattice channel. Local air suction from the crushing plant should also be provided.
When installing grilles with periodic manual cleaning, natural ventilation of the room is allowed.
Measures should be taken to prevent the entry of cold air into the room through the inlet and outlet channels of the grilles.
62. Sand traps should be provided when the productivity of the treatment plant is more than 100 m 3 / day. The speed of wastewater movement in them should not exceed 0.3 m / s. at their maximum inflow and 0.15 m / s. with minimal flow. Mechanized removal of sand from sand traps is mandatory if its amount is more than 0.5 m 3 /day. For sewage treatment plants with a capacity of up to 2,000 m 3 /day, the use of sand traps with drainage for sand dehydration is allowed.
63. For drying sand coming from sand traps, special platforms or storage tanks are provided.
64. The number of sedimentation tanks for domestic wastewater must be at least 2, provided that all of them are working. Sludge removal from primary settling tanks should be mechanized or under hydrostatic pressure, from secondary settling tanks - under hydrostatic pressure.
All types of primary clarifiers must have facilities for the removal of floating substances.
65. The duration of the sedimentation of the waste liquid in the settling tanks must correspond to the calculated data.
66. In the event of the release of wastewater clarified in primary settling tanks into a reservoir, the amount of residual suspension should be taken in accordance with the "Rules for the Protection of Surface Water from Wastewater Pollution" .
67. Pre-aerators, bioflocculators and clarifiers are recommended to be used if it is necessary to reduce the content of contaminants in the settled liquid in excess of what primary settling tanks are capable of providing, as well as in the presence of industrial effluent impurities that have an adverse effect on activated sludge.
68. Special structures such as sedimentation tanks are used as sludge thickeners. In sludge thickeners, as a rule, it is necessary to send activated sludge from secondary settling tanks to the sludge mixture from aerotanks.
69. For artificial biological treatment, high-load drip biofilters, biofilters of great height, aerotanks, aerotanks-settlers, aerotanks with a double inlet of sewage, two-stage aerotanks, aerotanks-mixers are used.
70. Crushed stone, hard rock pebbles and expanded clay can be used as feed material for biofilters.
71. The distribution of waste liquid over the surface of biofilters should be carried out with sprinklers, jet sprinklers or rolling sprinklers.
72. The number of sections or biofilters should be taken at least two, and all of them must be working.
73. Drip biofilters are designed for complete purification of waste liquid to BOD 20 = 15 mg/l. Their use is allowed for a capacity of not more than 1,000 m 3 /day.
At an average annual air temperature of up to plus 3 °, biofilters of any capacity, and at an average annual air temperature of more than plus 3 ° and up to plus 6 ° - biofilters with a capacity of up to 500 m 3 / day should be placed in heated rooms with five air changes per hour and an estimated internal air temperature 2° above the temperature of the waste liquid. Biofilters with a capacity of more than 500 m 3 /day at an average annual air temperature of more than plus 3 ° to plus 6 ° should be placed in unheated lightweight premises.
74. Highly loaded biofilters are designed for complete (BOD 20 = 15 mg/l) and partial cleaning and are used for treatment plants with a capacity of up to 50,000 m 3 /day. With appropriate justification, they can also be used for larger stations.
75. Highly loaded biofilters can be designed with natural and artificial aeration (air filters).
76. High-altitude biofilters, with appropriate justification, can be used for treatment plants with a capacity of up to 50,000 m 3 /day. Biofilters are designed for complete (BOD 20) purified liquid up to 20 mg/l and partial purification of waste liquid.
77. Aerotanks can be used for complete (BOD 20 purified liquid - 15 mg/l) or partial biological treatment of waste liquid. With complete purification of the waste liquid with bringing the final BOD 20 to 15 - 25 mg/l, aerotanks are designed without regenerators or with regenerators. The device of the latter is mandatory in the following cases:
a) when the BOD 20 of the waste liquid entering the aerotank is more than 250 - 300 mg/l;
b) in the presence of harmful industrial impurities in the liquid.
78. Aerotanks-settlers are designed in the form of rectangular tanks, divided by longitudinal inclined partitions that do not reach the bottom into aeration and settling zones. The arrangement of aerotanks, round in plan, with an annular inclined partition is allowed.
79. Aerotanks with a double inlet of sewage can be used to treat liquids with BOD 20 and the concentration of suspended solids in treated water up to 20-25 mg/l. They settle down with regenerators.
80. Two-stage aerotanks are used when the BOD 20 of the incoming liquid is from 250 mg/l or more, bringing the BOD 20 of the purified liquid to 15 - 20 mg/l.
81. Aerotanks-mixers can be used to treat wastewater with an initial concentration of up to BOD 20 to 1,000 mg/l.
82. Digesters are used to ferment sediments from primary and secondary sedimentation tanks and excess activated sludge.
Note:
Together with the sewer sludge, it is allowed to supply other organic substances to the digesters after their crushing (garbage, waste from grates, industrial waste of organic origin).
83. Digestion of sludge in digesters is designed under conditions of mesophilic (fermentation temperature 38°) and thermophilic process (53°). Digested sludge can be used in agriculture after drying in sludge beds or vacuum filtration and thermal drying, and for sludge digested under mesophilic conditions, composting is also required.
Notes:
1. Fermentation under thermophilic conditions should be provided for when the humidity of sediments loaded into digesters is not more than 94%; at higher humidity, the choice of the fermentation method (thermophilic or mesophilic) should be made on the basis of sanitary and epidemiological requirements and technical and economic calculations, taking into account maximum heat recovery.
2. Further processing of the digested sludge should be taken depending on the local conditions of its use in agriculture. At the same time, for sludge fermented under mesophilic conditions, the following can be used: drying on sludge beds and subsequent composting; supply of non-dehydrated sludge through the sludge pipeline to soil decontamination sites; vacuum filtration and thermal drying. For sludge digested under thermophilic conditions, the same except for composting.
84. The number of digesters should be at least two, all digesters should be working.
85. In areas with an average annual air temperature of at least plus 6 °, when industrial wastewater is discharged into the city sewerage and the territory is limited for placing sludge sites at wastewater treatment plants with a capacity of up to 50,000 m 3 / day, it is recommended to use two-stage digesters.
86. It is allowed to arrange sludge beds on a natural basis provided that groundwater occurs at a depth of at least 1.5 m from the surface of the pits and only in cases where, for sanitary reasons, sludge water is allowed to be released into the ground.
With a shallower depth of groundwater, it is necessary to provide for a decrease in their level.
87. If there is a lack of territory, it is recommended to arrange silt pads with tubular drainage laid in ditches filled with crushed stone or gravel.
88. Drainage wastewater from sludge sites, if it is impossible or inadmissible to release them into the ground, should be sent to treatment facilities for processing or neutralization.
89. It is allowed to install two to four-stage sludge ponds instead of sludge platforms, while the sludge water from the last stage should be directed to mechanical wastewater treatment facilities.
90. Mechanical dewatering of digested sludge should be applied depending on local conditions and three feasibility studies.
91. Thermal drying of sludge after vacuum filters should be carried out in drum dryers.
92. Filtration fields, as well as silt fields and irrigation fields, are not allowed to be arranged in areas directly bordering on places of wedging out of aquifers, as well as in the presence of fractured rocks and karsts that are not covered by a water-resistant layer.
They should be arranged on sands, sandy loams and located downstream of the ground flow from water intake facilities at a distance from them, determined by the radius of the depression funnel of the water intake well, but not less: for light loams 200 m, for sandy loams 300 m and for sands - 500 m .
When the filtration fields are located upstream of the ground flow, the distance from the filtration fields to the water intake facilities should be taken taking into account the requirements of the sanitary protection of the water supply source.
93. The norms for the load of clarified wastewater on filtration fields depend on the type of soil, the average annual air temperature and the depth of groundwater.
Soil name |
Average annual air temperature in degrees |
Loads on filtration fields in m 3 / ha per day when groundwater occurs at a depth (in meters) |
||
Light loam |
from 0 to +3.5 |
|||
over +3.5 to +6 |
||||
over +6 to +11 |
||||
over +11 to +15 |
||||
sandy loam |
from 0° to +3.5 |
|||
over +3.5 to +6 |
||||
over +6 to +11 |
||||
over +11 to +15 |
||||
Sands |
from 0 to +3.5 |
|||
over +3.5 to +6 |
||||
over +6 to +11 |
||||
over +11 to +15 |
Note:
For areas with an average annual rainfall of 500 - 700 mm, the load norms should be reduced by 15 - 25%, for areas with an average annual rainfall of more than 700 mm - by 25 - 35%. At the same time, a greater percentage of load reduction is accepted for light loamy soils, and a smaller one for sandy soils.
94. It is recommended to plant willows and other moisture-loving tree plantations along the contour of filtration fields and silt areas, 10-20 m wide, depending on the distance of filtration fields from populated areas.
Protective rollers along the slope and ridge should be sown with grasses with a rapidly developing root system, planted with shrubs or other woody vegetation.
95. For the period of spring thawing of frozen sewage and repair of filtration field maps, there should be backup maps, the area of which must be justified and should not exceed the usable area of filtration fields:
a) in III and IV climatic regions - 10%;
b) in the II climatic region - 20%;
c) in the I climatic region - 25%.
96. Maps of filtration fields intended for freezing sewage should provide for the release of melt water, taking into account the "Rules for the protection of surface water from pollution by sewage".
97. Drainage in filtration fields (open or closed) is mandatory when groundwater occurs at a depth of 1.5 m from the surface of the maps, regardless of the nature of the soil, as well as at a greater depth of groundwater with unfavorable filtration properties of soils.
98. At the filtration fields, a shower room, a room for drying overalls, a room for rest and eating, booths for heating service personnel (at the rate of 1 booth for every 30 hectares of the area of filtration fields) should be provided.
99. The area of communal irrigation fields is determined based on the following load rates:
Average annual temperature in degrees |
agricultural crops |
Load on irrigation fields in m 3 / ha per day, depending on the nature of the soil |
|||
skinny clay |
loams |
sandy loam |
sands |
||
0 to +3.5 |
garden |
||||
field |
|||||
Over +3.5 to +6 |
garden |
||||
field |
|||||
Over +6 to +9.5 |
garden |
||||
field |
|||||
Over +9.5 to +11 |
garden |
||||
field |
|||||
Over +11 to +15 |
garden |
||||
field |
Notes:
1. For areas with an average annual precipitation of 500 to 700 mm, the load norms should be reduced by 10 - 15%, and for areas with an average annual precipitation of more than 700 mm - by 15 - 25%. At the same time, a greater percentage of load reduction is accepted for loamy soils, and a smaller percentage for sandy soils.
2. The choice of agricultural crops for cultivation in irrigation fields is made depending on local conditions and in agreement with the local bodies of the sanitary and epidemiological service.
100. For communal irrigation fields, it is necessary to provide maps of filtration fields for receiving wastewater during the preparation of irrigation fields for sowing, as well as at the time of harvesting, etc.
101. Irrigated agricultural fields should be designed on the lands of state farms and collective farms for round-the-clock and year-round reception of sewage, using the latter for fertilizing and irrigating crops.
102. Arrangement of agricultural irrigation fields is not allowed:
a) in territories with groundwater at a depth of less than 1.25 m from the surface of the earth, if their level cannot be lowered;
b) in territories located in the area of supply of artesian and deep free-flowing waters, as well as in the presence of fractured rocks and karsts not covered by a water-resistant layer.
103. Sanitary requirements for the arrangement of agricultural fields are regulated by special rules.
104. Biological ponds as independent treatment facilities may be used with appropriate justification for populated areas located in the IV climatic region. Ponds can also be used for post-treatment of wastewater in combination with other treatment facilities.
105. Biological ponds can be built on weakly filtering soils.
106. The number of stages in treatment ponds should be: 2-3 stages for biologically treated wastewater, 4-5 stages for settled wastewater.
107. The estimated load on the ponds is accepted: for settled wastewater without dilution up to 250 m 3 / ha per day, biologically treated up to 5,000 m 3 / ha per day.
The average water depth in the ponds should be, depending on local conditions, not less than 0.5 m and not more than 1 m.
108. Disinfection of wastewater should be provided at stations for both mechanical and complete or partial biological wastewater treatment.
109. Disinfection should be provided by liquid chlorine. The estimated dose of chlorine is assigned:
a) at mechanical treatment stations - 30 g / m 3 for settled wastewater;
b) at stations of complete artificial biological treatment - 10 g / m 3;
c) at stations of incomplete biological treatment - 15 g / m 3.
110. At treatment plants with a capacity of up to 1,000 m 3 /day, the use of bleach is allowed, while the calculated dose of chlorine should be taken taking into account the active part of bleach.
111. The number of solution tanks must be at least two, and the concentration of chlorine in the solution - 2.5%.
112. The duration of contact of chlorine with the waste liquid in the tank or outlet trays and pipelines must be at least 30 minutes.
113. In the room of the chlorination room, when chlorinating with liquid chlorine, the following should be provided: an emergency exit directly to the outside and a heating system to maintain the temperature not lower than +18 °.
114. Liquid chlorine warehouses should be designed in accordance with special sanitary rules for the design, equipment and maintenance of warehouses for the storage of highly toxic substances.
125. To ensure the efficient operation of structures, it is mandatory to fulfill the following conditions for their operation.
Grids:
a) regular removal of waste as it accumulates;
b) three crushers - crushing waste and dumping them into the channel in front of the grates.
Note:
In the absence of crushers, waste is collected in closed receivers with filling them with a layer of bleach, peat powder and subsequent incineration of the collected waste, neutralization in a biothermal chamber or removal to sewage fields.
Sand traps:
a) compliance with the design speed of wastewater movement;
b) periodic cleaning of sand traps from sediment in order to avoid its deposition above the calculated level and removal by water current;
c) drying of sand extracted from sand traps on special sites.
Note:
Unwashed sand is subject to export to the places indicated by the local authorities of the sanitary and epidemiological service.
Primary clarifiers - horizontal, vertical and radial:
a) uniform distribution of the waste liquid over the sump in compliance with the calculated speed of its movement;
b) monitoring by personnel of the serviceability and cleanliness of the gutters supplying and discharging waste liquid, as well as the serviceability of other distribution devices (semi-flooded boards in horizontal sedimentation tanks, a central pipe and a reflective shield in vertical sedimentation tanks);
c) timely removal of accumulated sludge from settling tanks (daily or at least every 2-3 days) in order to avoid a decrease in the estimated capacity of settling tanks and sludge decay;
d) daily removal of floating substances, light impurities and fat (crust) from the surface of the water.
Two-tier sedimentation tanks:
a) regular monitoring of the correct operation of the settling chutes and obtaining a well-digested sludge;
b) monitoring the uniform distribution of the waste liquid along the settling chute, keeping in good condition the inlet and outlet trays, semi-flooded boards, etc.
c) breaking up at least once a week the crust formed on the surface (outside the gutters) and immersing it in water;
d) systematic removal of floating substances;
e) when signs of acidic fermentation appear (foaming of sediment, release of a significant amount of hydrogen sulfide) - turn off the sump from operation, lower the water level in it, release part of the sediment and mix the contents of the sludge.
Note:
To restore the alkaline reaction, the addition of milk of lime or preliminary chlorination of the wastewater entering the sump is allowed.
f) In case of insufficiency of these measures, the sump is emptied, flushed and put into operation again.
Septic tanks:
a) timely removal of silt and crust, cleaning of weirs and tees at the inlet and outlet of wastewater.
Note:
When cleaning septic tanks, about 20% of its contents are left, which is necessary for bacterial contamination of newly incoming sediment.
b) warming winter time septic tank top with peat, straw.
Silt pads:
a) proper maintenance of distribution gutters and protecting shafts of the drainage system;
b) uniform sedimentation on the maps in layers 20 - 30 cm thick in summer and 10 cm below the height of the ridges in winter;
c) the absence of silty (non-filtering) areas and overflows through the edges of the gutters and trays;
d) drying and use of sludge;
e) treatment and disposal of drainage water.
Notes:
1. Unloading of sludge beds must be done in summer in dry weather or in winter when the sediment freezes.
2. When drying unfermented sludge, its surface on sludge beds should be covered with a layer of dry earth or peat.
Biofilters:
a) uniform distribution of waste liquid over the surface of the biofilter;
b) good condition of the loading material in accordance with the instructions of the project;
Note:
With a satisfactory condition of the feed material and the correct operation of the biofilter, stagnation of the waste liquid should not be allowed on its surface.
d) When surface silting of the filter material appears and the resulting water stagnation on the surface of the biofilter, it is necessary to loosen the wetlands with a metal rake and rinse with a jet of water under pressure.
Notes:
1. In the warm season, silting is eliminated by turning off the biofilter section for 5-7 days. It is also used to add chlorine and bleach to the water supplied to the biofilter, in the amount of 35 - 50 g of chlorine per 1 sq. m of filter surface.
2. Periodic chlorination of water entering the biofilters with small doses of chlorine (3-5 g per 1 cubic meter) helps to reduce odor and kill midges (psychod);
e) protection of the distribution system in winter from freezing;
Notes:
1. The operating conditions of air filters are similar to those of biofilters.
2. It is necessary to take into account the compliance of the amount of air supplied to the air filter with the calculated amount.
Aerotanks:
a) observance of the duration of stay of the waste liquid in the aerotank established by the calculation in accordance with the actual changes in the BOD of the waste liquid entering the treatment plant and purified;
b) observance of the required quality of sludge and the timeliness of air supply to activated sludge (see p. a);
c) uniform air supply throughout the aerotank site;
d) timely removal and treatment of activated sludge so that its excessive concentration is not created;
e) the absence of dead spaces in the aerotank that contribute to the accumulation of activated sludge;
f) prevention of the removal of suspended particles into the reservoir.
Filtration fields and irrigation fields:
b) uniform distribution of wastewater on the maps and compliance with the established load limits;
c) seasonal periodic irrigation of filtration fields for 2-7 days, depending on the filtration capacity of the soil.
Notes:
1. Inlet sewage in the summer time to produce once every 5 days.
2. With a decrease in the filtration capacity of the soil, plowing and harrowing the plots.
3. Pouring of sewage in late autumn into deep furrows with a layer of 20 - 30 cm and under the formed ice crust the flood of sewage during the winter;
d) to control the amount of incoming wastewater, it is mandatory to have measuring devices when wastewater enters the treatment plant;
e) allocation of reserve sites to ensure wastewater treatment during the period of preparatory and agricultural work in the main sections of irrigation fields;
f) in the presence of fields of underground filtration and subsoil irrigation - ensuring the systematic cleaning of the septic tank in order to avoid the removal of sludge into the drainage network.
Biological ponds:
a) compliance with seasonal restrictions on the use of biological ponds as a treatment facility;
b) uniform distribution of the waste liquid over the volume of the ponds and unhindered passage of the waste liquid to the ponds of the next stage.
Wastewater disinfection:
a) the correct selection of the dose of active chlorine.
With the correct dose of chlorine, after thirty minutes of contact, the amount of residual chlorine in the waste liquid should be at least 0.5 mg per liter (0.5 g per cubic meter).
b) control over compliance with the established doses of chlorine and registration of the amount of chlorine consumed in the journal;
c) ensuring vigorous mixing of the waste liquid with chlorine water;
d) systematic removal of sediment from the contact tank.
126. Mandatory is the implementation of management and maintenance personnel sewer facilities the following requirements:
a) at least once a year medical examinations persons in direct contact with the waste liquid or sediment;
b) passing by the staff of planned preventive vaccinations against intestinal infections and examination at least 2 times a year for anthelmintic, followed by deworming;
c) suspension from work of persons associated with contact with sewage or sediment, with cuts, scratches or abrasions on their hands;
d) providing workers with first aid kits equipped with everything necessary for first aid;
e) providing workers with overalls and safety devices without the right to take them home;
e) obligatory presence of a shower with eyeliner hot water for those working in wastewater treatment plants.
127. For labor protection of workers in the chlorination room and warehouses, it is necessary:
a) ensuring the tightness of the dosing equipment and maintaining it in good condition;
b) ensuring the possibility of neutralizing chlorine in case of malfunction of cylinders (presence of tanks with hyposulfite solution, storage of gas masks at the entrance to the chlorination room).
128. Owners of treatment facilities (communal services, industrial enterprises and other economic organizations) are obliged to exercise production control over the efficiency of wastewater treatment and conduct systematic laboratory studies of wastewater.
Research should be carried out according to a plan agreed with the state sanitary supervision authorities.
When drawing up a laboratory research program, it is necessary to proceed from the composition and nature of wastewater, treatment methods and the category of the reservoir into which wastewater enters.
129. Examination of sewage should be carried out at the following points:
a) three receipts of wastewater at the treatment plant and at the final stage of treatment - in order to determine the effectiveness of treatment;
b) at the intermediate stages of wastewater treatment - in order to control the smooth operation of the relevant parts of the treatment facilities.
An exemplary analysis scheme and its scope in assessing the effectiveness of wastewater treatment are given in Appendix No.
130. The state sanitary supervision authorities evaluate the hygienic efficiency of existing treatment facilities on the basis of studying the compliance of the conditions for the discharge of treated wastewater with the requirements for the composition and properties of water in reservoirs at drinking and domestic water use points (Rules for the Protection of Surface Water from Pollution by Wastewater No. 372-61) .
Application No. 1
1. Name of the institution, enterprise, organization responsible for the condition and operation of treatment facilities, their address.
2. Location of treatment facilities, time of their commissioning (year, month, date).
3. Objects served by treatment facilities (residential sector and the number of inhabitants in it, industrial enterprises, medical institutions, etc.).
4. The nature and composition of structures.
5. Quantity and composition of wastewater, for which the facilities are designed, the actual amount and composition of wastewater entering the facilities.
6. Calculation requirements for the composition of the treated waste liquid in relation to the Rules for the Protection of Surface Water from Pollution by Waste Water No. 372-61 Mechanical
Settling tanks horizontal, settling tanks vertical
Reducing the content of suspended solids and increasing transparency
Waste water color, odour, transparency, sludge content by volume and suspended solids content by weight.
The production control of treated wastewater in small facilities consists, at a minimum, of daily sampling and determination of the sludge content by volume compared to the sludge content of the source water.
Mechanical
Two-tier settling tanks
The same clarification effect for the liquid phase of wastewater. Changing the properties of the sediment (improvement appearance, elimination of stench, destruction of its colloidal structure, compaction).
When processing sludge in digesters, the efficiency of digestion must be determined by the same indicators as for sludge fermented in the septic part of a two-tier settling tank.
Biological
Filtration fields, irrigation fields, biological ponds, cleaning using biofilters, aeration tanks with the expectation of complete cleaning
Mineralization of wastewater organic matter, reduction in the content and change in the composition of suspended solids, changes in the external properties of wastewater (color, transparency, smell).
Temperature, color, smell, transparency, sediment content by volume and suspended solids by weight, pH, oxidizability, BOD 5 stability, ammonium nitrogen content, nitrite, nitrate.
Waste water disinfection
Complex of facilities for disinfection of waste liquid with chlorine
A sharp decrease in the total number of bacteria in the water, a significant decrease in the E. coli index, the release of wastewater from pathogenic microbes
Bacteriological study with the determination of the total number of bacteria in 1 ml and the index of Escherichia coli; determination of pathogenic (according to indications). Determination of residual chlorine in waste liquid.
Note:
If the facilities receive not only domestic, but also industrial wastewater containing harmful substances, the analysis should be supplemented by the quantitative determination of these substances.
The construction of a sewer system in any suburban area is a complex of complex works, which involves not only laying pipes, but also installing a cesspool or a ready-made septic tank. It requires permission from the SES. You can't do without collecting a package of documents. Why is this required? The problem is that groundwater and the soil itself can be contaminated with runoff and chemical waste. Improper cleaning of the septic tank with chemicals can lead to various diseases, infection of the residential area of the entire site. Therefore, before starting work, it is necessary to design a sewerage system, collect a package of documents and submit an application to the SES.
Before the construction of the sewer system, you need to make a project, then collect the necessary documents and submit an application to the SES.
Documentation package
A septic tank is an installation for the accumulation and treatment of domestic waste. Not only liquid, but also solid waste, harmful gases, and microorganisms accumulate in sewer tanks. Such installations require constant monitoring by sanitary and epidemiological supervision. This makes it possible to protect groundwater from contamination, prevent the spread of various diseases, and runoff from entering the residential area. For the safety of both yourself and those around you, you must obtain the appropriate permission to use the septic tank.
How to get permission from the SES and where, what package of documentation will you need to collect? Among the main documents that will be required in the SES, it is worth noting:
- availability of a technical passport;
- a detailed diagram of the device of the septic tank, which will help to draw up in the design organization;
- project for a residential building;
- a package of documentation on the ownership of the site and building;
- detailed topological survey of the entire site (obtained by the relevant organization);
- an agreement with various organizations on the removal of all liquid household waste.
After the documentation package has been assembled, you can apply to the SES for. This is done either in the bodies of the sanitary epidemiological station of the region or in the organization for the protection environment. It must be remembered that the application is submitted only together with the documentation package. Permission SES will have to wait about a month. There is one more point in for suburban areas. SES after installing the storage tank for wastewater has the right to conduct scheduled and unscheduled inspections. Employees have the right to check the quality of wastewater treatment and the content of the septic tank.
Location conditions
You can’t just put a septic tank or a cesspool on the site, as any sewer system poses a certain danger. If permission from the SES for installation has been received, you can proceed to the external sewerage system. There are certain rules that regulate the distance from various objects, the depth of the pits and other conditions.
To obtain permission from epidemiological stations to place a septic tank, you will have to choose the right place for the tank.
Today, SNiP 30-02-97 and SanPiN 42-128-4690-88 have a whole list of requirements for the location of cesspools on the territory of a personal plot:
- storage pits should be located on the territory adjacent to a private house, it is not allowed to drain drains beyond the boundaries of the site without an appropriate connection and permission;
- the cesspool for drains should be located at a distance of 10 m from the water conduit and 20 m from the drinking well so that there is no contamination of the clean drinking water household waste, chemicals and effluents;
- the distance from the septic tank to a residential building and other structures should be approximately 10-12 m. A closer location can lead to flooding of the foundation in the spring, destruction of building structures;
- there should be a distance of 1 m from the septic tank to the fence;
- the depth of the cesspool should not be more than 3 m, otherwise its maintenance will be difficult. A thick layer of silt and solid sediments will constantly accumulate at the bottom.
Device options
Today it is possible to install various designs of cesspools for the storage and partial processing of wastewater. It can be:
- ordinary cesspools;
- engineering systems for the accumulation and partial processing and separation of wastewater mass.
The simplest option, which is provided by the relevant licensing services, is cesspools that do not have an equipped bottom. They are constructed if the daily volume of wastewater that is discharged from a residential building is not more than 1 m³. Sewage pits arrange below the level drinking water so that the water in the well is not contaminated with drains.
When installing a septic tank on a personal plot, you must remember to comply with all sanitary standards and obtain the appropriate permit. Sanitary standards regulate the location of the septic tank, establish minimum distances for laying other communications on the site. Taking into account SES and installation of a septic tank in relation to the location of a residential building and other buildings. It is worth being prepared for periodic checks of the employees of the sanitary and epidemiological station. But do not take this categorically, as all this is done for the safety of you and others.
Sanitary and technical measures for the collection, removal, disposal and disposal of waste are called sanitary cleaning.Waste is divided into liquid and solid. Liquid waste - sewage (household, industrial, storm, agricultural, etc.). Solid waste - construction waste, street estimates, waste from public catering, industrial and commercial enterprises, slag from boiler houses, etc.
There are 3 waste disposal systems: floating (sewerage), export, mixed.
Liquid waste - enter the sewer. Sewerage - a system of facilities that receives, transports wastewater through a network of pipelines outside the settlement to sewerage basins, from which wastewater is discharged to treatment facilities by collectors. In the absence of sewerage, the export is carried out by tankers to the drain stations.
Stages of wastewater treatment:
1. Mechanical cleaning. Efficiency reaches up to 50%. For cleaning, grates are used to trap large debris; sand traps for settling heavy particles; settling tanks for settling undissolved suspended solids.
2. Biological treatment - ensures the breakdown and mineralization of organic matter. For this, filtration fields, irrigation fields, biofilters (crushed stone, slag), bioponds and aerotanks (in which a mixture of wastewater and activated sludge flows) are used.
3. Disinfection of waste water. Use bleach. Sludge (sludge) is neutralized in digesters with the formation of methane gas. Efficiency is evaluated by coli-index (not more than 1000) and residual chlorine (not less than 1-1.5 mg/l).
The question of how to treat wastewater from food enterprises and the complex of necessary treatment facilities in each specific case decided on the basis of quantity chemical composition and sanitary and epidemic significance of wastewater. When using the central sewerage, wastewater treatment is carried out in the central sewerage system. However, before being discharged into the sewer, wastewater, as a rule, undergoes partial treatment (with sand traps, grease traps, etc.).
So, for the correct removal of wastewater from the meat processing plant, four sewerage networks are provided: the first - for the removal of relatively clean water from boilers, refrigeration, pumping units; the second - for industrial waters from fat, sausage, by-product and other shops (before descending into the network, wastewater is freed from fat by passing through special grease traps); the third - for the diversion of household fecal water and industrial water that does not contain fat; the fourth - to remove infected and highly contaminated water coming from the quarantine department, isolation ward, sanitary slaughterhouse and raw material department of the fodder and technical products workshop. Such waters must be subject to mandatory disinfection before being discharged into the general network.
If it is not possible to centrally sewerage small individual facilities for wastewater treatment, small sewage facilities are organized that can receive and process from 25 to 1000 m3 of wastewater per day. These structures are located outside a small settlement or a separate facility and can be represented by settling tanks with digested sludge, small filtration fields without a drainage device, irrigation fields, and various biofilters. In order to decontaminate sewage sludge in small sewage schemes, settling tanks of a special design are used, combining the processes of settling the sewage liquid and sludge fermentation. The most widespread are septic tanks and two-tier sedimentation tanks.
Collection solid waste is carried out with the help of garbage chutes, stationary garbage collectors and replaceable containers. For the removal of waste, special garbage trucks are used. A promising method is the use of special pipelines - pneumatic waste disposal.
All waste must be disposed of to prevent the spread of infections. Neutralization methods should be epidemiologically safe, ensure rapid disposal of waste, prevent the development of fly larvae and create a favorable environment for the development of rodents, quickly convert organic substances into safe compounds that do not rot and do not pollute the air, protecting groundwater and surface water from pollution. Whenever possible, it is necessary to use useful qualities of waste.
Waste is divided into recyclable (not destroyed and used as biofuels, fertilizers, etc.) and non-recyclable (necessarily destroyed).
Neutralization methods by technology are divided into:
For biothermal (composting, landfill, filtration and irrigation fields);
Thermal (burning of waste in special furnaces at a temperature of 1000-1200 °C; pyrolysis to produce combustible gas and oil-like oils at a temperature of 1640 °C);
Chemical (hydrochloric or sulfuric acid at high temperature in order to obtain ethyl alcohol);
Mechanical (pressing into building blocks).
The most widely used biothermal and thermal methods. The best is the biothermal method, which is often used in the form of composting. Due to the vital activity of thermophilic microorganisms, biochemical processes occur in the compost at a temperature of 50-70 ° C, organic substances are mineralized, and pathogenic microbes, helminth eggs and fly larvae die. The composting process lasts from 3 to 12 months. Ripened compost is a loose, odorless, loose mass of dark earthy color, which is used as a valuable fertilizer.
Sanitary and epidemiological requirements for sewerage and solid waste disposal at catering establishments. The sanitary well-being of a public catering establishment largely depends on proper organization removal of liquid and solid waste.
Removal of liquid waste. At public catering enterprises, liquid waste is removed using internal household and industrial sewerage, which is equipped at all enterprises, regardless of their capacity and degree of landscaping.
The device of the sewerage system must comply with the requirements of current building codes and sanitary and epidemiological rules.
All wastewater is discharged to a system of centralized treatment facilities, and in their absence, according to the sanitary and epidemiological conclusion of the sanitary and epidemiological service, to a system of local sewage treatment facilities.
The internal sewerage system for industrial and household wastewater must be separate and have independent outlets to the on-site sewerage network. At the same time, the level of release of industrial effluents should be higher than the level of release of household and fecal waters. All rooms equipped with washing baths, sinks, toilet bowls and drains should not be located below the level of on-site sewerage, which is adjacent to the food facility. Horizontal sewerage outlets from all production facilities must be equipped with pipe cleaning devices, and “breathing” risers are arranged at the end sections of the outlets to prevent sewage from being sucked in during salvo discharges from the equipment.
It is not allowed to lay internal sewer networks with domestic and industrial wastewater under the ceiling of dining rooms, industrial and warehouse premises of enterprises. Sewer risers are not allowed to be laid in dining rooms, production and storage rooms. It is allowed to lay risers in plastered boxes without revision only in production and storage facilities.
It is important to ensure that technological equipment and washing baths are not contaminated by the contents of industrial sewage. For this purpose, they are connected to the sewer network with an air jet break of at least 20 mm from the top of the receiving funnel. All receivers of internal sewage must have hydraulic seals (siphons).
For large enterprises mandatory requirement is also the installation of facilities for the treatment of wastewater from fat, starch, sand before the latter enters the external sewer network.
When a public catering enterprise is located on the ground floor in residential buildings and buildings for other purposes, it is necessary to provide for the isolation of the industrial and household sewerage network of the enterprise from the utility and fecal sewerage of these buildings. For this, the sewerage system of the enterprise is connected to the city network in separate outlets. Household sewer risers from the upper floors of residential buildings and buildings for other purposes are allowed to be laid only in horizontal or vertical technological channels. Sanitary facilities located above the enterprises, showers and bathrooms must have floors with waterproofing.
All production workshops, as well as washing, loading, defroster and food waste storage chambers, are equipped with drain ladders with a floor slope towards them.
In all public catering enterprises under construction and reconstruction, toilet bowls and sinks for washing hands of personnel should be equipped with special devices that exclude contamination of hands (elbow, pedal drives, etc.).
In the vestibule of the toilet for staff, it is necessary to provide a separate tap with a mixer for taking water intended for washing the floor. The crane should be located at a height of 0.5 m from the floor and have a drain with a slope towards it.
All stationary catering establishments must have toilets and sinks for washing hands for visitors. It is not allowed to combine toilets for staff and visitors.
Temporary quick service establishments (pavilions, tents, vans, etc.) must be located in places equipped with public toilets.
It is not allowed to discharge untreated sewage into open reservoirs and absorbing wells.
Removal of garbage and food waste. The accumulation of garbage and food waste at the enterprise can be a source of pollution with foul-smelling poisonous gases (for example, hydrogen sulfide), as well as contribute to the reproduction of microorganisms and the appearance of flies, insects, rodents, which sharply reduces the level of sanitary condition of the enterprise.
Collection of food waste in industrial premises and washing departments is carried out in special containers of small capacity. They are stored in a refrigerated waste chamber at a temperature not exceeding 2 ° C and taken out daily. The location of the waste chambers should provide a minimum path for waste to be removed from the washing compartments.
Separate containers with lids must be used to collect garbage and food waste on the territory. Containers are installed on sites with a hard surface, the dimensions of which exceed the area of the containers by 1 m along the perimeter.
The garbage collector area must have a sanitary gap of at least 25 m from residential buildings, playgrounds and recreation areas.
Garbage bins are released when no more than 2/3 of their volume is filled, after which they are cleaned and disinfected using products approved by the sanitary service.
Currently, there is a planned and regulated system of garbage disposal, which provides for its daily removal outside the city. At the same time, an important hygienic measure is the careful isolation of garbage both during its storage in waste bins and during transportation. It has been estimated that from one dustbin in unsanitary conditions, several tens of thousands of flies per day can breed in the summer. From a hygienic point of view, the system of replaceable containers is the most acceptable for the collection and removal of solid waste.