LAWI - Recirculation Gas System
Without coolant, solid waste fuels burn at temperatures at up to 1,800 °C. In order to avoid adherence deposits (ash melting) in the combustion chamber as well as damages to the boiler (high temperature corrosion), cooling-down of the furnace temperature is required. The standard principles are:
- cooling down by excess air results in heat losses and high amounts of exhaust gas and, therefore in low efficiency
- cooling down by water-wall chambers results in low flexibility for multi-fuel application
The solution is the LAWI EtaComb® Combustion System with recirculation gas technology for furnace temperature control and cooling purposes: highly flexible multi-fuel application combined with high efficiency. The combustion recirculation gas system provides combustion air and recirculated flue gas to the combustion chamber to allow a controlled and evenly distributed combustion and heat generation at all stages. The LAWI EtaComb® Combustion System operates on an automatically controlled, optimal air supply level with a very low excess air rate keeping the oxygen content below 4 %. This results in combustion efficiency over 98 % and very low emissions regarding CO, NOx, and unburned hydrocarbons.
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Automated Radar-Controlled Fuel Dosing System
The hydraulic driven LAWI EtaComb® Fuel Dosing System provides a reliable and fully automated processing of feedstock into the combustion -
Fire Protection System
LAWI`s advanced ignition control and backfire protection system combining low oxygen content reci-gas supply with a hydraulic driven guillotine gate to safely control fuel ignition even for high calorific fuels (such as RDF) and protect the fuel dosing system. -
Moving Step Grate
LAWI`s hydraulic driven moving step grate with independent speed control of each grate zone allowing optimal fuel retention time in each combustion zone (drying zone, ignition zone, combustion zone and burn-out zone -
Air & Gas Supply System
The LAWI EtaComb® operates on optimal air supply level with a very low excess air rate keeping the oxygen content 3-4 %. This results in combustion efficiency over 98 % because CO emissions and unburned hydrocarbons are kept on very low rates. -
Refractory & Adiabatic Design
The adiabatic (heat insulated) combustion design with multi-layer brick lining that not only insulates but is highly resistant against chemical attacks during the combustion process -
Post-Combustion Chamber
The LAWI EtaComb® post-combustion chamber design allows for an optimum protection of the highly stress exposed super heater coils from erosion and fouling and a complete burn-out of flue gas with 2 seconds after last air injection -
Advanced Automation System
LAWI EtaLogic®, the customized control and optimization system signficantly increases process stability and simplicity of operation for combustion and boiler, profiting from advanced MPC, adaptive controllers and using LAWI’s long-term know-how in biomass and solid wastes power incineration design.