Pilot Development of Polygeneration Process of Circulating Fluidized Bed Combustion combined with Coal Pyrolysis

Abstract

A pilot polygeneration process of a 75 t h -1 circulating fluidized bed (CFB) boiler combined with a moving bed coal pyrolyzer was developed based on laboratoryscale experimental results. The process operation showed good consistency and integration between boiler and pyrolyzer. Some critical operating parameters such as hot ash split flow from the CFB boiler to the pyrolyzer, mixing of hot ash and coal particles, control of pyrolysis temperature and solid inventory in the pyrolyzer, and pyrolysis gas clean-up were investigated. Yields of 6.0 wt-% tar and 8.0 wt-% gas with a heating value of about 26 MJ m -3 at 600°C were obtained. Particulate content in tar was restrained less than 4.0 wt-% by using a granular filter of the moving bed. Operation results showed that this pilot polygeneration process was successfully scaled up.

Characteristics and application of co-pyrolysis of coal/biomass blends with solid heat carrier

“…In order to realize the efficient and clean utilization of coal, a polygeneration process, which was coupled circulating fluidized bed (CFB) combustion (15 t/h coal and gangue feeding, 75 t/h steam output) with coal pyrolysis (5 t/h coal feeding), was finished in a pilot-scale [25]. In the poly-generation process, a pyrolyzer was set beside the CFB boiler and connected with it.…”

Pyrolysis Characteristics of Corn Stalk with Solid Heat Carrier

“…The experiments above demonstrate that biomass can be pyrolyzed by the hightemperature ash from the CFB boiler. But if the whole poly-generation system can operate successful, the pyrolysis stage should be operated combined with the boiler, just as the reference stated with coal (Liang et al 2007;Qu et al 2011). Such work can be regarded as a priority for future studies.…”

“…However, previous studies of biomass pyrolysis with high-temperature ash from a circulating fluidized bed (CFB) boiler as the solid heat carrier, which can rapidly pyrolyze biomass, are limited. This technology was inspired by coal pyrolysis with a solid heat carrier and poly-generation system, as studied previously in our laboratory (Liang et al 2007;Qu et al 2011). In a poly-generation system, a pyrolyzer is installed beside the CFB boiler.…”

Integration of coal pyrolysis process with iron ore reduction: Reduction behaviors of iron ore with benzene-containing coal pyrolysis gas as a reducing agent

“…The coal pyrolysis gas obtained at low temperatures mainly consists of hydrogen, carbon monoxide, carbon dioxide and methane, which generally accounts for 85v%-95 v% [17,18], with the rest is C2 and C3 with a very low amount. The composition of the simulated coal pyrolysis gas prepared in this work is shown in Table 1, which is made by referring to the gas composition from sub-bituminous coal pyrolysis at low temperatures [19].…”