Herbst Gasmiser

The Herbst Gasmiser - Simple, safe and convenient

• It eliminates creosote build up and the hazards of chimney fires.
• It burns peat cleanly
  Significantly reducing smoke emissions.
• It can efficiently burn hard wood or soft wood chips with a moisture content up to 50% and many other biomass fuels and industrial wastes.
• It can be fitted to most new or existing boilers

How The Herbst Gasmiser Works

The Herbst Gasmiser is designed to burn various types of low grade fuels at high thermal efficiency and low pollution rates.

Combustion of the fuel is divided into two stages, gasification and combustion. In the first stage preheated primary combustion air is introduced and at this point the fuel is decomposed to hot gas and glowing carbon. The reaction between oxygen in the air and carbon in the fuel supplies sufficient heat for a second reaction. The second reaction produces carbon monoxide, a major combustible component of the producer gas. The steam, including hydrogen and a small quantity of methane.

In the following stage the gas is drawn into the combustion tunnel and secondary combustion air introduced. Ignition starts in this zone and the gas is completely burned in the combustion tunnel and the combustion chamber of the boiler or air heater.

The heat output is controlled by regulating the downward flow of fuel in the hopper and by adjustment of the primary and secondary combustion air dampers. With the Herbst Gasmiser this is fully automated.

Fuels

1. The individual particle size is between that of a prime fit and a 50mm (2 inch) cube.
2. The calorific valve, as determined on a Par Bomb (ASTM d20 15) is greater than 10.5 MJ/kg as delivered to the Gasmiser.
3. Ash fusion point is above 1100oC in a reducing atmosphere.
4. For efficient operation and maximum plant life it is generally recommended that the fuel moisture content should not exceed 35% net weight.
5. The fuel is available in the required quantity throughout the economic life of the installation. (The fuel can be any combination of materials meeting the guidelines).

Construction of the Herbst Gasmiser.

The Gasifier.
The Gasifier has been manufactured from a high rate fire proof mass and is insulated with a rigid mineral wood board. In the base of the Gasifier is an ash container and above this the grate and grate bears. The grate height can be adjusted by a control lever outside the casting. The grate is designed especially for the gasifier and the particular fuel used. It is made from a special cast iron. Located above the grate is the most important component of the Gasifier, the reactor.

The reactor and it's supports are made from a high chrome alloy, especially developed for this application. In the front there is a well sealed cleaning door which also contains the control damper for preheated primary combustion air.

The Fuel Hopper.
The Fuel Hopper is a gas tight construction of 1mm, mild or stainless steel (dependent on fuel used). The loading door is sealed with a heat resistant strip.

The Combustion Tunnel.
The Combustion Tunnel is made from the same fireproof mass as the Gasifier and is fully insulated.

Operation of the Herbst Gasmiser. The Herbst Gasmiser is easy to install and simple to operate. The fuel is gravity fed to the Gasifier and the heat output control is automatic. An occasional visit to replenish the hopper and remove the ash is all that is required. In most cases this would be once a day or less. Chimney Sizing. Generally the existing chimney is suitable. However in some cases the chimney must be up graded or changed. The following graph gives an indication of chimney sizes for various Boiler/Herbst Gasmiser combinations. Optional Extras. Automated Fuel Handling and Filling Systems. Automated Ash Removal Systems. Motor Driven Grate Vibrators. Low Cost Large Fuel Storage Units.   Technical details. There are 4 types of gasmisers available: G-30, G-60, G-100 and G-200.   Parameters Type G-30 G-60 G-100 G-200 Heat capacity , KWt 30 60 100 200 Efficiency., % 90 90 90 90 Fuel consumption, kg/h,          - sod peat 9 18 30 57  - wood chips 10,5 21 34 65 Volume of bin, m3   0,37     0,5     0,75     1,35   Start time, hours, not more 0.5 0.5 0.5 0.75 Dimensions, mm:         - length 1300 1400 1500 1500 -width 700 800 800 1300 -height (with bin) 2350 2500 2600 2700 Weight, kg, not more 290 380 400 700   Special equipment with gasmisers Using gasmisers special equipment for air and water heating was developed. Air heaters Parameters Type AH-30 AH-60 AH-100 AH-200 Gasmiser type G-30 G-60 G-100 G-200 Nominal heat capacity, KWt 24 48 80 160 Capacity by air volume, m3 per hour 2000 3000 5000 6000 Heat exchanging surface, m2, 10,1 19,8 Air temperature,  ºC 40 - 80 Electric motors capacity, KWt         -air fan 1,5 4,0 4,0 5,5 -smoke fan   0,55 0,55 0,55 0,55 Efficiency, %, not less 70 Dimensions, mm:         - length 2630 2730 3270 3270 - width 1600 1800 2200 2520 - height 2350 2530 2620 2680 Weight, kg, not more 1750 1850 3800 4170     Water heater Volume of water tank, liters 300 Temperature of the heated water, °C 75±5 Time of heating, hours , not more 1,5 Fuel consumption, kg per cycle   - wood chips 12-15 - sod peat 8-10 Weight, kg, not more 760