Experimental Investigation On Co-combustion Characteristics Of Oil Shale Retorting Residue With Bituminous Coal

Oil shale is a kind of potential and tremendous energy. Among the fossil fuels,its reserve in terms of the calorific value is only next to coal and ranks the secondplace. Retorting residue of oil shale(semi-coke), which has a low calorific value, is asolid waste material left after oil shale retorting. Large areas of land have been usedfor dumping of retoring residue. At the same time, the seepage from the retoringresidue heaps contains potential pollutants with harmful environmental effect. Thispaper proposes a method to burn retoring residue with bituminous coal blends incirculating fluidized bed boiler. The ash can be utilized as building material whencarbon content of the ash is less than3%.After of cold-state test, thermal debugging, and remending of the CFB pilot, theperformance was perfected and operated on the whole. In addition, it was provedthat the pilot can be burned with many kinds of solid fuels was proved.In this thesis, experimental study on combustion performance of semi-coke andbituminous coal was conducted. Experimental investigation the fuel mix ratio andthe wind rate influence of the temperature on bed; And the smoke of burningproduces in the process of composition,bottom ash and fly ash is analyzed and thecombustion efficiency was caculated under different working conditions.Experiment show that, combustion performance was improved with the increase ofbituminous coal mixing. Dense and rare phase temperature increases with the windrate decreases. The content of nitrogen oxides is less than400mg/Nm3and thecontent of sulfur dioxide is less than900mg/Nm3.The pollutants in the flue gas aremet with the national standards (GB13271-2001).The retorting residu, in terms ofexperiment, can be utilized by means of CFB. The fuel that about thirty percentbituminous coal is mixed into semi-coke and sixty-six piont percent of the wind ratewill suit for CFB, which is showed by experiment. The study work of this thesis could provide testimony and direction to design a CFBB (Circulating Fluidized BedBoiler) for semi-coke.