Energy & Fuels, Vol.26, No.11, 6792-6802, 2012
Comparative Study of Gasification Performance between Bituminous Coal and Petroleum Coke in the Industrial Opposed Multiburner Entrained Flow Gasifier
A comprehensive three-dimensional numerical model for simulating Shenfu bituminous coal and petroleum coke in the industrial opposed multiburner (OMB) gasifier is established. The effectiveness factor method is used to extrapolate the intrinsic char reactivity data to industrial gasifier conditions. With the proposed models, the predicted gasification performance of Shenfu coal is in good agreement with industrial operating data, and the predicted carbon conversion of petroleum coke is about 96.7%. Comparing with Shenfu coal, the specific solid fuel consumption of petroleum coke is lower, while the specific oxygen consumption is higher. The characteristic of char gasification in the entrained flow gasifier is investigated. In the high temperature jet flow region and impinging flow region, when the particle diameter is above 200 mu m, the Thiele modulus of the char gasifying with steam for Shenfu coal and petroleum coke are 15.4 and 4.8, respectively. Therefore, pore diffusion has a significant effect on the apparent char reactivity : :white for the char gasifying with CO2, the Thiele Modulus is below 5 in different regions of the OMB gasifier, and the apparent char reactivity is affected by the chemical reaction and pore diffusion: When the char reactivity of petroleum coke is accelerated at 5 times by catalysis effects, the carbon conversion reaches 99.2% and the consumption of oxygen and feedstock decrease obviously. Importantly, the temperature at the dome of the gasifier decreases to 1345 degrees C, which prolongs the life of refractory Wall and favors a long period of-availability for the gasifier.