The cement clinker production line with a daily output of 5,000 tons can generate 21-240,000 kWh of electricity by using waste heat every day, which can solve about 60% of the problem of self-use electricity in clinker production, reduce the comprehensive energy consumption of products by about 18%, save about 25,000 tons of standard coal and reduce about 60,000 tons of carbon dioxide emissions every year.
Pure low temperature waste heat power generation technology of cement refers to that in the production process of new dry cement clinker production line, a large number of low-grade waste gas waste heat discharged from the kiln head and kiln tail of cement kiln is recovered by waste heat recovery device-waste heat boiler, and superheated steam is generated to push the steam turbine to realize the conversion of thermal energy to mechanical energy, thus driving the generator to generate electricity, and the generated electric energy can be used in the cement production process. 1, kiln head adopts waste heat boiler (or heat exchanger), referred to as AQC furnace, which is vertical in China; So are foreign countries.
2. Waste heat boiler (or heat exchanger) is used at the kiln end, and vertical SP boiler is mostly used in China, and horizontal PH boiler is used in Anhui Conch Kawasaki Engineering Co., Ltd.; Foreign countries are horizontal. The performance comparison between horizontal boiler and vertical boiler is shown in the following table: the forced circulation natural circulation mode of PH boiler SP boiler is small in volume, convenient for on-site layout, light in weight, perpendicular to the heat exchange tube, not easy to accumulate dust, good in dust removal effect, easy to accumulate dust, difficult to remove dust, less in maintenance, less in heat exchange terminal difference, and higher in evaporation than vertical 15%~30% and lower than horizontal. The heat exchange efficiency is 8%~ 10% higher than that of the vertical type and 8%~ 10% lower than that of the horizontal type. The heat exchange terminal difference in the above table refers to the temperature between the boiler inlet exhaust gas and the superheater outlet steam. The heat exchange end difference of PH boiler is about 65438 00℃, and that of SP boiler is close to 30℃.
3, steam turbine, domestic steam turbine; All foreign countries are mixed-pressure steam turbines.
4. Generator, domestic air-cooled generator; So are foreign countries.
5. Water treatment equipment.
6. Circulating cooling equipment.
7.DCS control equipment.
There are three commonly used methods: single pressure without steam supplement, flash evaporation (single pressure steam supplement) and double pressure steam supplement to generate electricity with waste heat;
1, the single-pressure steam supply system refers to the main steam with similar parameters generated by the waste heat boiler at the kiln head and the waste heat boiler at the kiln tail, which enters the steam turbine after mixing; The hot water generated by the kiln head waste heat boiler is supplied to the steam parts of the kiln head waste heat boiler and the kiln tail waste heat boiler. Domestic technical representatives include Sinoma Energy Saving-Tianjin Institute and Nanjing Kaisheng Company.
2. Double-pressure steam make-up system means that steam with higher pressure and lower pressure generated by waste heat boiler enters the high and low pressure steam inlets of steam turbine respectively. Domestic technical representatives include Luoyang Zhongxin and Dalian Yida.
3. The flash system refers to the main steam and hot water with certain pressure generated by the boiler. The main steam enters the high-pressure inlet of the steam turbine, and the hot water flashes to generate low-pressure saturated steam, which is added to the low-pressure inlet of the supplementary steam turbine. The domestic technical representative is Anhui Conch Kawasaki Engineering Co., Ltd.