Coke oven flue gas waste heat and CDQ waste heat coupled power generation system and coupled power generation method

Abstract

The invention relates to a coke oven flue-gas waste-heat and dry-quenching waste-heat coupled power generation system and a coupled power generation method thereof. The system comprises a dry-quenching waste-heat recycling device and the dry-quenching waste-heat recycling device comprises a dry-quenching furnace and a dry-quenching waste-heat boiler which are communicated with each other. A dry-quenching secondary superheater, a dry-quenching primary superheater, a first evaporator, a second evaporator, a coke oven flue-gas waste-heat superheater and a dry-quenching economizer are sequentially arranged in the dry-quenching waste-heat boiler. A coke oven flue-gas waste-heat recycling device comprises a coke oven. A coke oven flue-gas main channel is connected to the coke oven and sequentially connected with a coke oven flue-gas waste-heat economizer, a coke oven flue-gas waste-heat evaporator, a coke oven flue-gas draught fan and a coke oven flue-gas chimney. A steam turbine generator unit, the dry-quenching waste-heat recycling device and the coke oven flue-gas waste-heat recycling device form a loop through a condensing unit. According to the coke oven flue-gas waste-heat and dry-quenching waste-heat coupled power generation system and the coupled power generation method, coupled power generation is achieved in the manner that coking flue exhaust fume waste heat enters dry-quenching waste-heat power generation circulation in a coupled manner, and the purposes of efficient utilization of secondary energy and energy saving and emission reduction are achieved.

Description

technical field [0001] The invention relates to a coke oven flue gas waste heat and CDQ waste heat coupled power generation system and a coupled power generation method thereof, belonging to the field of waste heat power generation. Background technique [0002] With the rapid development of the national economy, the production capacity of my country's coking industry has also experienced rapid growth. According to relevant data, in 2012, there were 299 large-scale coke ovens with a capacity of more than 500,000 tons in my country, and the total coke production capacity reached 408.21 million tons. In the coking equipment and technology commonly used in my country, the temperature of the waste gas produced by the coke oven is generally between 220°C and 260°C, and the sensible heat contained in the waste gas of the coke oven produced per ton of coke is 19426KJ / ton (coke). The recoverable sensible heat contained in coke oven exhaust gas in the industry is as high as 7.93×10 1...

AI Technical Summary

Problems solved by technology

[0006] The manufacturing technology is not yet perfect, and the thermoelectric conversion efficiency is only about 8%.

[0007] (2) Relatively high investment

figure 1 It is a schematic diagram of the CDQ power generation system in a coking plant. It can be seen from the figure that the exhaust gas temperature of CDQ is 178.5°C, and the thermal efficiency of the waste heat boiler is also low. Due to the expansion of high-temperature gas, the power consumption of the circulating fan is also low. higher

At the same time, it can also be seen from the figure that the heat transfer temperature difference between the cold and heat sources of each heating surface is relatively large, so the loss of CDQ waste heat power generation technology is relatively large

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