Waste incineration power generation furnace type, mainly mechanical grate incinerator, rotary kiln, circulating fluidized bed furnace and pyrolysis gasifier. China's waste incineration power generation technology started late, after years of development, combined with China's economic and technological level and the characteristics of municipal waste, the formation of a mechanical grate incinerator and circulating fluidized bed incinerator as the main waste incineration power generation furnace type of the status quo
Rotary kiln incinerator in the treatment of toxic and hazardous hospital garbage or chemical waste advantages are obvious, while incineration of low calorific value of municipal garbage is difficult, while the construction of rotary kiln, the incineration of low calorific value of municipal waste is difficult. Compared with the rotary kiln, pyrolysis gasifier, mechanical grate incinerator and fluidized bed incinerator in the waste incinerator has more prominent advantages:
(1) good fuel adaptability. On the one hand, it is suitable for combustion of complex components of municipal waste, on the other hand, it can be suitable for incineration of low calorific value, high moisture waste.
(2) Single furnace capacity. At present, China's large-scale circulating fluidized bed incinerator single-furnace capacity has reached ?500t / d, Guangzhou City, LiKeng waste incineration power plant phase II introduction of Danish Weilun technology, incinerator single processing capacity of up to 750 t / d. Processing capacity, processing speed, so that the mechanical grate incinerator and fluidized bed incinerator effective solution to the garbage generation rate is too fast, the original landfill overload operation of the dilemma. Relying on the above advantages, mechanical grate incinerator and fluidized bed incinerator has become the main furnace type of waste incineration power generation in China, which is widely used.
Incineration treatment enterprises are actively introducing and digesting mechanical grate manufacturing process and technology. Mechanical grate incineration technology is currently the longest development time, the most mature technology incineration technology, is the mainstream technology of waste incineration. At present, waste incineration power generation in developed countries basically adopts the mechanical grate furnace combustion mode. Compared with the traditional coal-fired power plants, waste incinerators in actual operation have the following characteristics:
(1) Due to the unstable calorific value of the waste, and water content fluctuations, resulting in large fluctuations in the boiler load, the combustion control problem is more prominent.
(2) The excess air coefficient is large. Due to the large size of the garbage, in order to ensure that the garbage is fully combusted, it is necessary to increase the oxygen content in the garbage incinerator. Incinerator outlet flue gas oxygen content must be about 6% to 10%.
(3) the furnace chemical reaction is very complex. Garbage components are complex and variable, and the combustion characteristics of different components vary greatly, resulting in the overall chemical reaction of the garbage becomes very complex, chaotic system, difficult to accurately describe.
(4) There are differences in the types of corrosion. Garbage contains a large number of plastics, rubber, food waste, biomass and other components, chlorine content, alkali metals and volatile metal content is much higher than conventional fuels, the complex composition of the flue gas leads to the heating surface is very susceptible to corrosion, prone to pipe bursting accidents.
(5) flue gas treatment. Conventional coal-fired power plants are mainly dust removal, desulfurization, denitrification, and waste incinerators in the actual operation of the waste incinerator should pay particular attention to ensure that dioxin emissions meet the standards, based on the use of activated carbon, lime, water, urea, etc. to achieve the removal of pollutants, including dioxin, NO, SO and so on. /