Abstract
The aim of the paper is to compare effect of coal and steam supply to the second stage of the entrained-flow gasifiers on their main operating parameters. Two two-stage gasifiers of SB RAS Institute of Thermophysics were used as experimental units. The 5 MW unit has air-coal feeding to first and second stages (air-blown gasification). The 1 MW unit has air-coal feeding to first stage and steam feeding to second stage (air-steam-blown gasification). Experimental studies of air-blown and air-steam-blown gasification with various stoichiometric coefficients, flow rates, temperatures and supply points of secondary media (air-coal and steam) are carried out. Experimental and calculated (thermodynamic and CFD) methods have established that: in the air-blown gasification unit the increase of stoichiometric coefficients (secondary coal flow rate reduction) reduces the syngas heating value and increases the carbon conversion rate; in the air-steam-blown gasification unit the increase of the steam supply nozzle immersion to the gasifier leads to increase of the syngas heating value, the carbon conversion rate and decrease of the syngas H2/CO ratio.
Highlights
Coal is the most wide-spread type of fossil fuel on the planet and has one of the first places in the world fuel and energy balances
Experimental study Two two-stage gasifiers of SB RAS Institute of Thermophysics were used as experimental units
The 1 MW unit has air-coal feeding to first stage and steam feeding to second stage
Summary
Coal is the most wide-spread type of fossil fuel on the planet and has one of the first places in the world fuel and energy balances. The main element of this plant is gasifier, in which coal gasification takes place – coal conversion into combustible gas (syngas). The air contains 21% oxygen, so the gasification rate is low, which is usually compensated by using two-stage scheme gasifiers [2]. One of the most effective methods of the gasification process controlling is secondary media supply to the gasification chamber. Such media are usually coal, steam, carbon dioxide, combustion products, syngas, etc. Many years development and operation experience of MHI two-stage air gasifier confirmed the effectiveness of radial secondary coal feed into high-heated products of primary coal incomplete combustion [3].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
