Wood and coal boilers for the home. Solid fuel boilers on coal and wood are a real alternative to gas heating
Despite a common misconception, boilers designed to burn wood cannot burn coal and vice versa. The difference lies in the design of the combustion chamber, the principle and temperature of combustion.
To solve this problem and satisfy the numerous wishes of consumers, universal boilers firewood-charcoal.
The principle of operation of heating boilers on coal and wood
The design of a boiler that runs on wood and coal takes into account the difference between the two types of fuel. The difference is as follows:- Firewood and charcoal are burning different length flame. Coal, depending on the grade, during combustion forms a relatively low column of flame, or is burned in a flameless way.
- Coal combustion requires a large amount of oxygen. To ensure uniform combustion and a minimum residue of underburning, a special grate is installed. The function of the grate is not only to prevent spillage of coal, but, more importantly, to evenly distribute air throughout the combustion chamber and remove ash.
Universal boilers long burning on wood and coal, differ in the strength of the heat exchanger. During the combustion of coal, the temperature of the exhaust gases reaches 1300°C. The heat exchanger of wood-burning heating equipment, with such overheating, will quickly lose the integrity of the welds.
The difference between a wood-fired boiler and a coal-fired boiler is that the former remains operational with constant heating of the exhaust gases to 550 ° C and short-term heating up to 1000 ° C. Heat generator on coal, capable of transferring more than high temperatures without loss of performance.
The device of the boiler on wood and coal, allows you to use two types at once solid fuel, automate the combustion process and the supply of coal to the combustion chamber. At the moment, universal models available in two versions, differing in the degree of automation.
Boilers with manual supply of coal and firewood
Combined boilers operating on wood and coal in manual mode, with their appearance practically no different from single-fuel units. An additional door for fuel filling is provided in the upper part of the structure. The design is equipped with a large firebox, sufficient to accommodate up to 2-3 buckets of coal.Transfer from firewood to coal is carried out manually. Grates are inserted into the furnace. The air damper is opened several notches to ensure a better air flow.
Semi-automatic charcoal boilers
Another fundamental difference between working on wood and coal is the ability to automate the process of burning fractional fuel. A hopper equipped with a worm gear is connected to the structure. As the coal burns out, a new portion of fuel is added.Individual semi-automatic heating boilers on wood or coal of the usual type, are installed in a separate room to avoid smoke from entering the living rooms. Pyrolysis units are equipped with a forced smoke exhaust system. The ingress of smoke into the living quarters is excluded, therefore, installation in any other room in the house is allowed.
Long-burning dual-fuel coal-wood boiler, regulated by sensitive automation, the task of which, among other things, is:
- Control of coal supply to the combustion chamber - a fuel hopper is fixed on the boiler body. Feeding is carried out by auger or "drum". The volume of the bunker is sufficient to ensure autonomous operation of the boiler for 3-10 days.
- Ignition of coal - the design provides for electric ignition, automatic type. There is a sensor in the furnace that monitors the presence of fire and, when it goes out, gives a signal to ignite the fuel.
- Air supply and removal of combustion products. As already noted, burning coal requires more air than burning wood. In automatic mode, fans are turned on, increasing the intensity of the passage of air flows through the combustion chamber. Automation monitors the preheating and production of the air mixture, which ensures the best efficiency of the boiler.
- Self-cleaning system - automatic operation on coal does not completely eliminate the need for boiler maintenance. But, the self-cleaning system increases the interval between inspections. The unique design of self-cleaning movable grate dumps accumulated ash into a special box. Remove combustion products without stopping the boiler.
Semi automatic boilers are easy to operate, provide autonomy of combustion and reduce the need for maintenance. The owner is required to monitor the amount of coal in the fuel bunker and once every 1-2 months, remove carbon deposits from the combustion chamber.
How else can you heat a coal-wood boiler
In addition to coal and firewood, it is allowed to heat the boiler with wood and peat briquettes. Fuel is made from fine waste of the base material. Previously, peat or wood is crushed into dust. Then, by pressing high pressure, rectangular briquettes are formed.The advantage of using compressed fuel is:
- Humidity is not more than 12%, the optimal ratio for the process of pyrolysis or gas generation.
- The burning time is 3 times longer than that of firewood.
- The efficiency of the boiler when using briquettes increases up to 94%.
- The percentage of ash content is not higher than 0.4%.
When using a briquette, heat the boiler correctly, using ordinary dry firewood to ignite the flame. After the flame has flared up, the required volume of compressed fuel is laid.
How to choose solid fuel boilers for wood and coal
To select a dual-fuel boiler for coal and firewood, many technical aspects and parameters are taken into account, including the choice by country, manufacturer and cost. Additionally, the following factors are taken into account:- The rate of consumption of firewood.
- The operating principle used is the most economical boilers on coal and wood, for heating a private house, pyrolysis combustion is used. In the process of operation, the afterburning of the exhaust carbon dioxide is carried out separately, which makes it possible to obtain additional thermal energy.
- The degree of automation - heating the house with a semi-automatic long-burning coal-wood boiler, requires minimal attention from the owners. Refueling is carried out no more than in 3-10 days. Conventional classic dual-fuel units require manual refueling of coal or firewood. The maximum period of work from one bookmark to 12 hours.
Selection by country manufacturer
Modern innovative semi-automatic stations and standard classic boilers are offered by several dozen domestic and foreign manufacturers. Judging by customer reviews, heat generators made in Poland, Germany, the Czech Republic and Russia are the most popular:- German boilers are considered the best in quality and reliability. Automated stations work almost perfectly. It spoils the picture a little and limits popularity, only the high cost of production. Boilers are offered by several companies, including: Bosh.
- Czech boilers - in terms of quality performance and efficiency, are not inferior to German counterparts. Offered at the same price. It is believed that automatic boilers made in the Czech Republic are slightly better than German units, thanks to more sensitive automation. Products are offered by Atmos,.
- Polish boilers - products are offered by several manufacturers. You need to be extremely careful with the choice of products you like, due to the large number of fakes made in China. It is better to buy boilers from trusted manufacturers SAS, DREWMET.
- Russian wood-coal boilers - the first models offered by manufacturers, had many flaws. But, for now, effective domestic boilers working on coal and wood are no longer a rarity. Heat exchangers are made of cast iron and steel, the models differ high reliability. Boilers are mainly equipped with automatic equipment of foreign manufacturers. The products of companies Teplodar are popular.
The cost of bi-fuel charcoal boilers
A water-heating combined heating boiler for coal and wood, German-made, using the principle of conventional combustion, will cost from 150 thousand rubles. Pyrolysis units, on average, cost between 250-500 thousand rubles. Automatic stations, from 500 thousand rubles and more.Gas-generating wood-coal boilers for water heating, domestic production, will cost 55 thousand rubles. fully equipped. Ordinary, classic heat generator, from 15-25 thousand rubles. A fully automatic station running on wood and coal will cost about 200 thousand rubles.
Installing a wood and coal fired boiler
A boiler room for coal and wood must comply with the safety standards set forth in SNiP and PPB. In particular, the following standards must be observed:The safety of the people living in the house depends on the correct installation. Therefore, it is better to have the installation carried out by a qualified person.
What is more efficient to heat the boiler - coal or wood
Universal boilers can be fired not only with coal and firewood, but also with briquettes, wood chips, etc. A competent choice of fuel affects the energy efficiency of the equipment and, accordingly, its heat transfer and efficiency.The consumption rates of firewood and coal, the cost of each fuel and calorific value, differ significantly. To determine how efficiently to heat the boiler, the following parameters are taken into account:
- Calorific value - for anthracite, the coefficient is 31 MJ / kg, for firewood, with a moisture content of 20% - 14 MJ / kg, 45% = 11-12 MJ / kg. It turns out that if you heat with coal, it will take 2-3 times less than firewood.
- Cost - anthracite of a large fraction, costs approximately 7 thousand rubles. per ton. If we calculate the consumption of coal for the heating season, then for a house of 150-200 m², at least 5 tons will be required. For this money, it is possible to buy approximately 37 m³ of wood. And, if you plan to use a pyrolysis kolel, with high efficiency, achievable precisely when burning firewood, the choice of fuel is clearly not in favor of coal.
- Autonomous operation - the main advantage of universal units on coal and wood, it remains possible to eliminate the need for maintenance as much as possible. The supply of coal is carried out automatically. The boiler is able to work without human intervention from 3-10 days.
With a nominal boiler power of 10-15 kW, the consumption will be about 5 tons of coal per season or 15 tons of wood. Transferring such an amount of fuel manually is quite problematic.
Long burning boilers are heating devices. They burn firewood, coal or pellets, and the released heat is spent on heating water, which then enters the heating pipes and batteries. The long-burning boiler works regardless of the presence of gas. This is an autonomous device that requires minimal human participation in the operation process. The combination of independence from gas and the relative freedom of the owners of the house makes boilers popular in organizing heating.
Let's look at how long-burning boilers work, what are the advantages of heating with these devices, and how to choose a device for heating your own home.
A traditional charcoal stove takes time to fire up the stove and add wood. Every day, the owners should allocate at least 2 to 4 hours of personal time for heating the house. Unlike conventional wood-burning stoves, long-burning solid fuel boilers do not require the constant attention of the owners. After loading and lighting firewood, the stove independently regulates the air flow, combustion force and energy consumption. How is the adjustment carried out?
Boilers use the principle top burning. If in traditional oven all loaded firewood burns on firewood, then in the long-burning chamber the flame is only at the top of the masonry. As the wood (coal) burns, the flame moves down. Thus, the burning time of the entire volume of loaded firewood is at least 7-8 hours, and can reach 2-3, and even 6-7 days. Such a device, together with an automatic combustion controller, allows you to leave the house for several days and not worry that the room will freeze or be left without heating.
How to create conditions for upper burning?
In order to localize the flame in the upper part of the firewood, air is supplied to the combustion zone. Air preheating improves the completeness of fuel combustion and increases heating efficiency. The strength of the air supply and its volume determine the size of the flame, the rate of combustion of firewood and the temperature of the heated water at the outlet of the heating device.
Air is supplied by special devices - a fan and a telescopic air distributor. Their work is controlled by an automatic machine that operates from the electrical network. Therefore, for the operation of such a boiler, the presence of electricity in the house is necessary.
As the fuel burns, the air supply unit moves down. The flame moves lower and spreads to the next batch of coal (firewood). So gradually the air distributor tube reaches the bottom of the chamber.
Another principle of operation: pyrolysis
In addition to upper combustion boilers, there are heating boilers for pyrolysis fuel combustion. They work exclusively on wood. AT pyrolysis boilers there are two combustion chambers. In the first, firewood burns slowly - smolders, in conditions of lack of oxygen. In this case, gases are formed, which are called pyrolysis. In the second chamber, the resulting gases are burned under conditions of enhanced oxygen supply. Pyrolysis processes are characterized by complete combustion of fuel, without soot and residual impurities. Chimney not covered with soot.
Device
From the outside, a wood-fired or coal-fired boiler looks like a rectangular cabinet with doors. Firewood or coal is loaded through the top door. Through the bottom - the firebox is cleaned of ash.
The combustion chamber is located inside the boiler. It is made from cast iron or steel. The amount of loaded firewood and the duration of burning of the boiler on wood depend on the volume of the chamber.
Scheme of a long-burning boiler
Below the combustion chamber there is a container for collecting ash. It is separated from the firebox by a grate (grate). During combustion, air passes through the grate and rises. The ash formed during the combustion of the fuel wakes up down into the ash chamber (from which it is periodically removed).
In the upper zone of the combustion chamber there is a pipe with water. Here, in the upper zone, heat rises, which heats the water in the pipe. Then the heated water is fed into the heating system.
Advantages of long burning boilers
- Long battery life. Unlike a stationary stove, a long-burning boiler can work from 7 hours or more without constant human attention. When heating with wood, the maximum time battery life maybe 2 days, when heating the house with coal - up to 7 days.
- Efficiency (efficiency) of fuel combustion is higher than that of conventional furnaces, and is 92-98%. For daily heating, less energy is needed (by 30-40%). Which means less expenses for its purchase.
- Automatic adjustment, safety, the ability to adjust the temperature of the water in the heating system, the presence of an emergency switch.
- Versatility in the choice of fuel: it is possible to work on coal, wood, pellets.
- Low power consumption, battery operated. Electricity is required for the functioning of automatic controllers and the air supply fan.
Note: Heating boilers for solid fuel allow you to quickly organize heating, without a long project, expensive investments in gas equipment and connection to the gas network.
Which is better: wood or coal?
Long-term combustion heaters can operate on various types of solid fuels: wood, coal, pellets. Each type of fuel has its own characteristics and advantages.
Wood heating
Heating a house on wood - allows you to significantly save on energy costs (especially if you have the opportunity to harvest firewood yourself or purchase wood for affordable price). For kindling the stove, you can use branches from pruning trees, broken boxes, pallets. The purchase of firewood for the winter is cheaper than the purchase of coal for the same heating period. But the volume of firewood that will be required for heating is approximately 4 times more than the volume of coal.
In addition, they do not emit carbon monoxide and do not pose a risk of burning (unlike coal, which produces carbon monoxide when burned).
Coal heating at home
Heating a house with coal allows you to increase heat transfer (the heat capacity of coal is higher than that of wood) and increase the duration of self-burning fuel (instead of 2 days on wood - 7 days on coal).
For installation charcoal oven a separate room is required. Coal burns for a long time and does not completely burn out, it forms carbon monoxide gases. Therefore, for security reasons, do not close chimney completely so as not to burn. For the same reason, coal has to be frequently cleaned of soot. In addition, when coal is filled, dust rises, which pollutes everything around and penetrates into the lungs of a person. These facts confirm that a wood-fired boiler is simpler and more environmentally friendly than a coal one.
Also, heating briquettes and pellets are used as an energy carrier in long-burning boilers. They are made from pressed sawdust, sunflower husks, peat. The specific heat of combustion of briquettes is slightly lower than the specific heat of coal, but at the same time they do not form carbon monoxide, do not get dirty and are the subject of recycling (wood waste). Therefore, pellet heating is as popular as wood burning stoves.
How to choose a boiler?
A long-burning wood-fired boiler has several passport characteristics:
- power - the number of kilowatts of heat that a wood-burning boiler produces per hour of operation;
- area of the room - the total area of \u200b\u200bthe rooms of the house for which this device is intended for heating;
- burning duration - how many hours this unit can operate in automatic mode;
- Efficiency - the efficiency of using heat from the combustion of firewood.
Note: When choosing a heating boiler, the area of \u200b\u200bthe room and the characteristics of the operation of the unit are taken into account. They also evaluate the burning time indicated in the technical data sheet (which depends on the volume of the combustion chamber).
When purchasing expensive equipment, you want to be sure of its high-quality and durable work. Customer reviews about the operation of boilers will help you choose the brand of the unit, decide on the manufacturer.
Long-burning boilers: is it possible to do it yourself?
A ready-made wood-burning boiler for long burning has a rather high price. Often a person who owns a welding machine has a desire to make a boiler with his own hands. However, in the absence of installation skills, the savings can turn into an explosion. It is necessary to correctly calculate the power, weld metal parts with high quality and install the device correctly. In case of errors, the operation of the unit becomes dangerous not only for the owners, but also for the people around them.
Boilers for long burning on wood - drawing
Home-made long-burning heating boilers are distinguished by their clumsy appearance and unreliable automation. It is possible to build a top combustion boiler without automatic control. Weld a cylindrical furnace with a height of 1 to 15 m, weld grates in the lower part and make a chimney. Firewood in such a device will burn for several hours, but the efficiency and operation will not be as stable as that of a finished unit with automatic adjustment.
The long-burning furnace is a worthy alternative gas heating. It allows you to organize autonomous heating at home, not to depend on energy prices and work common system gas supply.
Remember the good old saying about sleds that are cooked in the summer? It is quite consistent in terms of preparation for the heating season. Especially if your house is not connected to centralized heating and the main gas pipeline. Until recently, there were practically no alternatives in such cases. furnace heating.
Indeed, the choice was not great either to stock up on firewood (coal) or to buy an expensive and energy-intensive electric heater, but everything changed when devices appeared that could run on coal, wood and other types of fuel. Now we can safely say that wood and coal boilers are a real alternative to centralized heating.
Rice. one Modern solid fuel boiler with control panelSolid fuel units are an excellent replacement for traditional stove heating, common in rural areas. Due to the fact that both coal and firewood serve as fuel in such heaters, they are environmentally friendly and economical.
The cost-effectiveness of coal-wood boilers is due to the fact that the latest generation devices allow you to maintain the desired temperature with a single fuel filling from 8 to 12 hours. Even if unforeseen difficulties arise with the replenishment of coal or wood reserves, the devices will be able to work for some time on diesel fuel, gas or pellets.
Types of solid fuel boilers
There is an opinion that coal wood boilers are able to work only on certain types of fuel, but this is not so. It follows that such devices should be classified according to the types of fuel used during their operation.
Rice. 2 Option for installation and installation of solid fuel boilers
The following boiler options are available:
- devices capable of operating exclusively on one type of solid fuel (classic) are the least demanding and the easiest to maintain;
- devices that use almost all types of solid fuels;
- universal devices operating on liquid, solid and gaseous fuels.
It is possible to classify coal-wood boilers according to the principle of their operation.
This classification includes equipment:
- with an additional device designed to facilitate the management of the boiler;
- devices that use not only wood and coal, but also directly the products of their combustion (pyrolysis combustion).
As you can see, coal and wood are far from the only type of fuel that wood-fired boilers use, which once again underlines their versatility and efficiency.
Even if it happens that after you have purchased a coal or wood-burning appliance, your house is connected to the main gas pipeline, you do not have to buy a new one, since solid fuel boilers are equipped with special adapters that allow you to work on main gas.
Most often, devices are made of steel or cast iron. To be more precise, heat exchangers of coal-fired boilers and their combustion chambers are made from steel and cast iron.
In both cases, there are certain pros and cons, since steel mechanisms are smaller and heavier, but cast iron ones are more durable and reliable.
Rice. 3 The device and principle of operation of heating boilers
When operating a boiler on wood and coal, it will save your family budget, since both coal and firewood, which are the main type of fuel for it, are much cheaper than other energy sources.
Modern coal-fired boilers can solve not only the problem of heating your home, but also the issue of having hot water for household needs. Agree that in winter period The lack of hot water makes a big difference. Especially in rural areas.
An important aspect is that such equipment is completely autonomous, that is, it can work independently of the mains.
When choosing a coal, wood or universal appliance, it is important to familiarize yourself with the operation features of such heating equipment. Please note that there are devices with automatic fuel loading (mainly these are units that use pellets as fuel) in such devices, it will be enough to feed fuel into a special container once a day, from which it will automatically be fed into the furnace as it is used. . However, the price of such equipment will be higher than that of similar models that need to manually replenish fuel in the furnace.
An equally important factor is the volume of a heated room on average in order to heat an area of 110-120 square meters it will be enough to purchase a product with a power of 12 kW.
Features of the operation of solid fuel boilers
- The so-called wood-burning or traditional (classic) boiler has been in operation for quite a long time. It is equipped with a traditional cast-iron firebox, which uses coal or firewood. The firebox in such units is traditionally located below.
- More productive and profitable for home use are hydrolysis boilers. The principle of their operation is a kind of separation of the fuel combustion elements into solid residues and gaseous products, also used as fuel. Such a wood-burning boiler, firstly, is very economical, and secondly, it is able to provide heat to fairly large areas for a long time.
- There are also solid fuel fireboxes of long burning. Such equipment is refueled once a day.
Despite all the advantages of solid fuel equipment, it still has a number of disadvantages. The main one is that a coal or wood-burning boiler cannot always work if the coal or wood is damp.
When operating solid fuel boilers, it is necessary to take into account the characteristics of the fuel used. Because the durability and quality of operation of solid fuel heating equipment depends on it. Experts recommend following a number of recommendations when using various kinds fuel.
- Firewood, when kindling, a large amount of smoke can be released. Therefore, it is desirable to place larger firewood at the edges, and place small ones in the middle of the hearth.
- Coal, for proper combustion, a fairly massive firebox is needed.
- It is not recommended to use peat in densely populated areas.
- Pellets (waste of wood, sunflower, straw crushed and compressed into granules) are used mainly in special units.
Almost all modern heaters are equipped with a fan control unit and a temperature sensor.
Such boilers, regardless of the fact that they use coal or wood as fuel, are able to maintain a certain temperature for a long time.
A coal and wood-burning unit today is able to provide heating and hot water supply to houses that are not connected to a gas heating system. Modern solid fuel devices provide safe and environmentally friendly combustion of fuel, thereby protecting the inhabitants of the house from possible negative consequences.
A huge advantage of using double-circuit heating mechanisms in rural areas is the possibility of heating water. Thus, solid fuel boilers can not only heat your home, but also provide your family with a constant supply of hot water throughout the entire heating season. Compared to the traditional method of heating water, solid fuel devices significantly save coal and wood used as the main fuel.
The advantages of solid fuel furnace equipment in a country rural house are undeniable. But this does not mean at all that such coal or wood boilers cannot be used to heat an urban private house or a small country house.
Advantages are visible from the fact that they are universal, environmentally friendly, safe. Due to their small size and ergonomic design, they can be easily placed in a country house, as well as in a city cottage or country house.
Rice. four Boiler internalsIf you live in a city cottage and want to install a solid fuel boiler for heating your home for a number of reasons, but you are embarrassed that you may encounter the problem of purchasing firewood and coal for kindling. Then, you should not worry, as you can safely replace firewood and coal, which are quite exotic in urban conditions, with a more modern and affordable type of fuel suitable for both coal and wood-burning devices. It's about pellets. modern form fuel, which is becoming increasingly popular.
Advantages of solid fuel boilers
- The clear advantage is that virtually all modern boilers are easily installed in both old and newer heating systems.
- Coal-fired appliances are widely used in small boilers and mini pumping stations.
- Solid fuel devices can be used as a separate heating unit, or in tandem with a diesel or gas equipment.
- Small dimensions will allow you to easily place your coal or wood-burning heating unit in any small-sized room.
- The efficiency of most boilers is 75-85%.
All these advantages can be achieved if the devices are properly operated and timely preventive maintenance is carried out.
Thus, the prevalence of solid fuel heating equipment is due to a number of factors. Regardless of the country of manufacture, all boilers on the market are economical and safe, do not require special skills for maintenance and operation.
Do not forget that fuel for heating equipment of this type is quite cheap and affordable (this applies to both firewood and coal, as well as pellets and all kinds of fuel briquettes). The cost of such devices also does not reach cosmic peaks, which makes them affordable for most buyers.
The price of such heating boilers mainly depends on their performance. The higher the performance of the device, the correspondingly higher its price. The same can be said about the dimensions of the boilers, the larger they are, the higher their cost will be.
In any case, solid fuel heating heating systems the latest generation are an excellent alternative to gas and electric heating appliances. By purchasing such a boiler, you will get rid of many problems, providing your family with a reliable source of heat for many years.