Biomass Waste Heat Boiler
Biomass Waste Heat Boiler (WHB)
Biomass WHB, aka Heat Recovery Boiler or Heat Recovery Steam Generator (HRSG), is specially designed for Biomass Combuster/Burner. Its basic flue gas parameter shall be offered by Client. Normally the flue gas temperature is very high, boiler is designed to be high temperature sub-high pressure (485°C, 6.7MPa) and superheated steam type . The superheated steam produced by boiler is used to generate electricity.
The boiler is designed as outdoor type with single drum, natural circulating water-tube, centralized down comer, π type structure, rainproof ceiling, all steel structure and all positive sealing. The heat surfaces are all hung on the steel frame. Gas flue is composed of membrane water wall. The gas enters the boiler at inlet of boiler, after heat exchange exits at the rear outlet.
The boiler superheater is divided into the high temperature, middle temperature and low temperature three parts. Two grades of desuperheater are set. In order to avoid the dust stuck on the HT superheater, the three parts superheaters are arranged in crossing sequence. In this boiler, the hot gas flushes
MT superheater -> HT superheater -> LT superheater.
The saturated steam from the drum goes
LT superheater -> Grade one desuperheater -> MT superheater -> Grade two desuperheater -> HT superheater -> Steam Turbine.
Considering hot air usage in different type of Combuster/Burner, the Air Pre Heater (1 stage or 2 stages) could be designed.