Comprehensive recovery and utilization system of exhaust gas and waste heat of sintering ring cooler

Abstract

The invention discloses a system for comprehensive recovery and utilization of exhaust gas and waste heat of a sintering ring cooler, which includes a flue gas circulation system; the flue gas circulation system includes a smoke collecting hood arranged above the conventional waste heat recovery section of the ring cooler, a chimney, a conventional air intake pipe, and waste heat Boiler, circulating fan and return air duct of annular cooler; the flue gas inlet and outlet of waste heat boiler are respectively connected with conventional air intake duct and return air duct of annular cooler, and the flue of waste heat boiler is equipped with superheater, evaporator, high pressure section economizer, the second condensate heater, the low pressure section economizer and the first condensate heater, and a steam drum is arranged outside the flue of the waste heat boiler; among them, the water inlet of the low pressure section economizer and the waste heat utilization unit The water outlet is connected, and the steam outlet of the superheater is connected with the steam inlet of the waste heat utilization unit; the water inlet and outlet of the first condensate heater and the second condensate heater are respectively connected in parallel with the low-pressure heater of the generator set. The invention improves the utilization rate of the waste heat of the waste gas of the sintering ring cooler.

Description

technical field [0001] The invention relates to the technical field of energy saving in the iron and steel industry, in particular to a system for comprehensive recovery and utilization of exhaust gas waste heat of a sintering ring cooler. Background technique [0002] Among the various processes of iron and steel production, the sintering process is a major energy consumer, and its energy consumption is second only to the iron-making process. The sintering ring cooler is the post-processing equipment of the sintering process, which is used to cool the temperature of the sintered ore to below 150°C. The high-temperature exhaust gas of the annular cooler is a valuable waste heat resource. Taking the annular cooler equipped with a conventional 198m2 sintering machine as an example, the flow rate of the high-temperature exhaust gas (temperature about 350-450°C) in the annular cooler section is as high as 200,000 Nm3 / h, if you can make full use of the waste heat of the exhaust...

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Problems solved by technology

This scheme can produce considerable economic benefits, and because the exhaust gas realizes a closed cycle, which effectively avoids the environmental pollution caused by the emission of particulate matter in the exhaust gas, it has become the most mainstream waste heat recovery method for annular coolers at present, but the scheme There are still major deficiencies: First, the exhaust gas temperature at the outlet of the waste heat boiler is still as high as about 150°C, and the higher return air temperature will have an adverse effect on the operation of the ring cooler: the higher cooling air temperature of the ring cooler will lead to the failure of the ring cooler. The deterioration of the operating environment will lead to easy damage to the dynamic and static seals, accelerate the deformation of the frame of the annular cooler, and cracks in the joints of the annular cooler; secondly, because the cooling air volume of the annular cooler is very large, the exhaust gas at the outlet of the waste heat boiler at about 150 °C contains Huge sensible heat resource, the sensible heat resource still has great usable value. If it is directly returned to the ring cooler in the conventional way, although the flue gas temperature in the high temperature section of the ring cooler can be increased to increase the output of the waste heat boiler to a certain extent , but there is still a large energy waste

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