Features of boilers with automatic feed
The elements of the boiler system that are directly responsible for burning fuel and transferring heat to the home heating system are not significantly different from conventional solid-fuel devices.
The main operational advantage of devices with automatic feeding is provided by the presence in their design of three basic components:
- Fuel hopper for one-time loading of large volumes of combustible materials;
- auger conveyor for regular transfer of fuel to the combustion chamber;
- complex automation responsible for the operation of the entire system.
The listed construction elements provide the possibility of long combustion without additional maintenance of the boiler unit. For the operation of such equipment the participation of a person is required not more than once in 1-2 weeks, and sometimes even less.
Automatics also regulates the amount of fuel supplied, which depends on the current temperature of the coolant and set in the settings. When the hopper is almost empty, the system notifies you to fill it.
Many models also have the possibility of automatic removal of combustion products. That is, the entire process, from ignition to cleaning, in these units is carried out without human intervention.
What else can these heaters run on??
Automatic boilers designed to work on wood chips can also work on:
When operating on sawdust and husk, the efficiency and maximum output of the boiler is reduced due to the peculiarities of combustion of these solid fuels. When operating on woodchips, efficiency and maximum power depend on the size of the chip and the type of wood.
When operating on coal or pellets, the boiler produces a higher output than on wood chips.
After all, coal has a higher calorific value, and pellets have a much higher specific density, so that for the same volume of wood mass is somewhat more.
THERE IS NO DOUBT: FROLING BOILERS ARE RELIABLE AUSTRIAN STYLE
thought through to the smallest detail. EACH ONE IS TESTED AND PRESSED.
Other boilers are not as reliable as Froling. Only a company as large as Froling, which produces more than 30,000 boilers annually, can afford a 90-minute pressure test of every boiler, a thorough inspection of every weld seam and the use of only the best components from the world’s leaders. Drives Belimo (Switzerland), ignition system Leister (Switzerland), smoke exhausters EBM Papst (Germany), actuators Linak (Switzerland), oxygen sensors Bosch (Germany). This, together with the tried and tested, reliable design guarantees many years of trouble-free operation. All boilers are manufactured at Froling’s own factory in Austria.
Boiler plants with wood chip boilers are daily used more and more in public utilities, wood processing and furniture industries.
Boilers for chips and sawdust can be used not only for heating but also as source of heat for technological processes of the enterprise (saw-timber drying, wood thermomodifying, drying of agricultural products etc).д.)
Wood chip boilers can be installed in any settlement or enterprise where there are raw materials for wood chip production. An important economic indicator for businesses, organizations or individuals. is the cost of heating.
Using wood chips and sawdust of local production as fuel we get cheap heat and recycle waste wood. During the combustion of wood chips in boilers produced by “Ecodrev-Tver” no harmful environmental contaminants are released.
Svetlobor is designed for G30 Austrian standard chips. Main fraction particle size 3.15P16mm, more than 80% by weight. P1mm fine fraction, less than 5% by weight. Coarse fraction of P45mm, maximum 1% weight. Maximum chip length P85mm. The maximum wood chip size is 3 cm square. Humidity less than 30%.
Net calorific value of pellets (10% moisture) 5.65 kWh/kg or 3.76 kWh/l bulk. The lower heating value of wood chips (30% moisture) is 3.44 kWh/kg or 0.876 kWh/l bulk. Hence, the volume of storage is 4 times larger. Cross section X auger speed is 4 times higher compared to pellet operation. The efficiency of the boiler on wood chips is 2% lower. About 90-92%. It is calculated from the calorific value.
Differences in the design of the boiler. The area of the grate is larger for drying the chips before burning. The presence of a pitch in the afterburner is for the same purpose. The auger pipe is square. At the end of the screw there is a mirror pen (coil with a reverse coil). Single-chamber bucket type fire lock, with knives for cutting long chunks of wood chips. Increased torque on all drives.
Automatic storage. only with spring agitator. Feeding by auger through a square tube of large cross-section.
Feeding the wood chips to the storage. with a tractor and a bucket. Carrying wood chips over long distances is the same as carrying water.
Any solid fuel unit can work on wood. But it would have to be reworked. To do this, you will need:
A hole in the outer part of the heater is cut 20-40 cm above the grates. Diameter must match the size of the pipe into which the auger is inserted. It must be welded to the hole, restore the outer wall, ensure tightness. After that cut sensors, controllers, assemble control unit. Connect the conveyor to the hopper, connect to the electric motor.
Blueprints and Schematics
To make a wood chip heater at home, you need to follow the instructions of experts. There are diagrams and drawings for this purpose.
For inquisitive gentlemen who are planning to purchase a solid fuel boiler on wood chips
This text requires special preparation of the reader and is not intended for the urban dwellers of warm apartments.
And then we remember that our fathers-commanders allowed us to collect deadwood.
And if you put deadwood through the wood chipper, then here you have wood chips for next to nothing.е. the cost of gasoline or el.the power of the wood chipper drive.
And here we are happily starting to choose a solid fuel boiler on wood chips.
Joy as that immediately disappears after familiarization with the zakordonnye boilers from Austria, Germany are just super.
We turn to the domestic manufacturer and see that the Russian device is actually no worse in its functionality than its European brethren.
We buy a boiler (I am referring to boilers from 20 to 32 kW), prepare wood chips, fill a container with wood chips / storehouse, from which the chips enter the boiler, include automatic mode, which provides continuous operation with the possibility of remote control, t.е. the boiler works and works, and the gentleman smoking a cigar in his office gets periodic messages on the internet that everything is OK!
And what asks the inquisitive reader ? This is the calorific happiness?
Not at all, or rather not at all, because it is necessary to gain experience in boiler operation, i. e.к. as it is required to gain experience in the operation of the boiler on wood chips.
The essence of the question: when you collect dead wood, the wood is naturally different and the wood chips are therefore different in dimension and calorific value, and the boiler has several interrelated parameters:
Froling T4 Wood Chip Boiler
To make wood chips homogeneous in dimension and calorific value is in principle possible, t.е. stir it native with all the fanaticism available, but it’s almost a feat of Hercules.
Therefore, it is necessary to use the same sieve when working with the chipper. 20 mm, and to collect deadwood only birches/aspen trees/alder trees, and rowan trees.
And when setting the parameters of automatic operation.look at the composition of the wood chips.
Buying wood chips at the sawmill, t.е. chips. Sawdust, which is obtained by debarking pine, is a rather cheap fuel, but the boiler works with many times more ash, and the smoke from the chimney is like a steam locomotive.
Modern domestic solid fuel boilers on wood chips and sawdust are fully autonomous stations, requiring refueling once or twice during the heating season. During operation, automatic fuel supply to the hopper and subsequently, to the burner device is used.
To increase the efficiency, instead of the usual way of burning wood chips, the principle of gas-generator or pyrolysis combustion is used. The supply of sawdust and air is controlled by means of sensitive automatics connected to the thermostats. The error in adjusting the heating medium, is only 1-2 ° C.
Principle of operation of the chip and sawdust burner
Solid fuel boilers for long combustion on sawdust and chips, working on the principle of gas generation or pyrolysis. A screw fuel feeder is used. The working principle of the chip boiler is as follows:
Freestanding hopper or room, is equipped with a double auger transfer. One auger is connected to a receiver in which the fuel is discharged, the second, to a small drum located on the boiler and connected to the burner. The rotating inlet auger design, ensures a continuous supply of chips.
Boilers for the combustion of shredded wood differ in the way the fuel is fed into the combustion chamber, and the method of combustion. The principle of operation of the boiler also depends to a large extent on this.
Energy-dependent units are equipped with augers, for continuous supply of chips from storage to the hopper, and from it directly to the combustion chamber of the boiler. The rate of fuel and air flow is regulated automatically depending on the temperature set on the thermoregulator. The smoldering charge allows a new batch of wood chips to ignite, and when the temperature of the heat medium reaches a preset value, the blowing of the combustion air and the fuel supply is turned off.
It is desirable that such units are equipped with fire safety systems, as fire can reach the fuel storage tank via the auger. In some designs, safety is achieved by the fact that the fuel flows upwards through the screw and only a limited quantity enters the combustion chamber through an intermediate hopper. In others, sensors are installed which, if necessary, shut off the air supply and then turn on the water for extinguishing.
In power-dependent boilers the combustion of wood chips can be carried out in the combustion chamber:
Energy-independent boilers can only be of pyrolysis type. They work by manually loading a portion of fuel into the hopper. Slow and efficient operation of the unit is achieved by the fact that such boilers use layer-by-layer combustion from below, where the loose fuel gradually sinks. The wood chips that are located above the combustion zone are heated, dried, and release pyrolysis gases that react in the afterburning chamber, and the dry fuel gradually burns. The efficiency of such units is no worse than the complicated automatic models.