The Research On Technology Of Mixed Coal Combustion For Guohua Taishan Power Plant 600MW Boiler

At this stage, the mixture combustion technology has been studied using in most thermal power plants, in order to adapt to the change of coal price market, reduce cost of power generation enterprise, and widen coal supply channels of power generation. But this technology is very complicated. Different strategies of mixing different coal and mixing ratio has a huge impact on the safty and economy of the unit.It is very necessary that the Power generation companies develop mixture combustion strategies according to their own characteristics.In this paper,we mainly choose the units of Guohua Taishan power plant as the research subjects to analysis their equipment and operational characteristics.In Guohua Taishan power plant,we burn Shenhua coal mixed with Australian coal、South Africa coal、and Indonesian coal, respectively. We specific research the different blending ratio of coal and different unit load impact on the safety and economy of the plant unit.These are our main conclusions:First. Compared with the Shenhua coal, Indonesian coal has characteristics that the lower kindling point and the better property of burnout, and the performance of coking are close to. Australia coal and South Africa coal ignition and burnout characteristics is a bit poor than Shenhua coal, but it still belongs to the coal with better combustion performance. From the point of view of the coking tendency, South Africa coal is relatively high, while the Australian coal is relatively low.Second.The characteristics of Indonesia coal is high moisture content and high volatile matter,it is a hard grind of coal with serious coking tendencies and more serious explosion tendencies, and the raw coal is not easy flow,so the mill outlet temperature must be controled scientificly and reasonably to make the ignition point far away from the burner nozzle when burning it in the boiler. Take this adjustment, to avoid coking phenomenon in the spout position, and maintain safe operation of the burner.At the same time,it is not recommended to use Indonesian coal separately. Indonesian coal can be mixed with Shenhua coal and South African coalThird. If the coal mixed whith African coal and Shenhua Coal be burned, it still has a stronger tendency of coking.But South African coal single burning or mixed with shenhua coal can accommodate the boiler of Taishan power plant. However, boiler soot-blowing operation should be strengthened. In addition, either South African coal single burning or mixed with Shenhua coal,It may be appropriate to increase the mill outlet temperature because the African coal is not easy to explode.Fourth. Let the Australian coal mixed with Shenhua coal be combust, If Australian coal accounted for more than 40% of total coals, the tendency of the slag is lower. In contrast,If Australian coal accounted for less than 40% of total coals, the conclusion is just the opposite.at this time,boiler soot-blowing operation should be strengthened.And when Australian coal single burning, operators need to raise the angle of burner to prevent the main steam temperature becoming low.Fifth. From the point of view of safety, environmental protection and the need for full load of unit, in Taishan power plant, burning Indonesian coal alone has a certain risk, so it is not recommended. Indonesian coal must be mixed with other coals.The mixing ratio of Indonesian Coals in the mixed coals should be less than 50%,and boiler soot-blowing operation should be strengthened to avoid coking. The overall performances of South African coal and Australian coal are better than Indonesian coal.We can choose one of them to complete separate combustion or choose different types of coal(Shenhua coal, Indonesian coal, etc.) to complete mixture combustion according to the operating requirement.