Author:Site Editor Publish Time: 2018-01-05 Origin:Site
With the increasingly fierce competition in the domestic waste incineration industry, in order to maximize the profitability of enterprises, we are actively exploring the possibility of an increase in the revenue generated by power generation (accounting for two-thirds of the total revenue of incineration plants) and an increase Space (the current feed-in tariff is 0.6 yuan / kWh, the upper limit of electricity consumption per tonne of rubbish is 280kWh). However, the most direct and effective way to increase the income from power generation Internet access is to increase the power generation steam parameters in order to increase the power generation efficiency and increase the efficiency of waste incineration power generation. In addition, with the improvement of economy, the national production level is improved, the garbage source classification policy is gradually perfected, the heat value of rubbish increases year by year, and the litter components are also simplified. All of these provide favorable conditions for the power plant to adopt higher-temperature sub-high pressure steam technology Technical conditions. At present, the waste incineration plants that use medium-temperature and medium-pressure steam parameters in China are Li Hang (6.4MPa, 450 ℃), Wuhan Xincou (6.4MPa, 450 ℃), Hubei Huangshi (6.4MPa, 485 ℃), Langfang 6.4MPa, 485 ℃), the rest are mostly medium temperature steam pressure parameters.
Compared with the mid-temperature and medium-pressure steam parameters and mid-temperature and sub-high-pressure steam parameters currently used in China, the temperature of the medium-temperature and medium-pressure superheater is about 400 ° C while the wall temperature of the medium and high temperature superheaters is 420-450 ° C; The temperature of the device is 450 ° C, and its wall temperature is between 470 ° C and 500 ° C. Medium temperature and high pressure superheater tube wall temperature corresponding to the metal corrosion rate is about medium temperature high pressure superheater tube wall temperature corresponding corrosion rate of 2 to 3 times. However, the first LiKeng waste incineration plant in China using medium-temperature and high-pressure technologies has been in operation for 6 years. With the mid-temperature and high-pressure design, due to the high steam temperature, the original designed superheater (material 15CrMoG) It takes two years to replace the superheater, the corrosion of the pipe far beyond the design life, and in 2008-2009, the factory boiler waterwall corrosion serious, frequent pipe burst, up to 20 times. This also shows that high temperature superheater corrosion in addition to high temperature and temperature, but also with the composition of the flue gas is concerned, and flue gas composition by the garbage composition, boiler operation and operation habits, heat recovery boiler structure design and many other factors.
However, the waste heat power station adopting medium-temperature and high-pressure parameters is the development direction of future waste incineration power generation. Some domestic experience of construction and operation of waste incineration has gradually begun to accumulate, but it is subject to different plant climate and waste components and the atmosphere in the furnace , In addition to using expensive imported corrosion-resistant materials, so far no effective measures have been found to prevent the rapid corrosion of the heated surfaces in the furnace when using high parameters. Therefore, at present, the incineration power generation uses medium-temperature medium pressure parameters (4.2 MPa, 405 ℃) Waste heat boiler is still the mainstream.