Residual heat recovery system of sewage water of coke dry quenching boiler

Abstract

The invention relates to a residual heat recovery system of sewage water of a coke dry quenching boiler. The system is characterized in that a sewage water heat exchanger is additionally arranged, desalting water which is delivered to an auxiliary coal saver by a water feed pump of a deaerator is used as a cooling medium to exchange heat with the sewage water nearby, and then the heat-exchanged desalting water is delivered to the deaerator to be deaerated. The system has the advantages that the problem of quantity distribution of water entering the heat exchanger and the auxiliary coal saver is avoided, and the operation and the control are convenient; the temperature of the desalting water entering the heat exchanger is minimum, the heat exchange temperature difference is high, and the heat recovery effect is good; the temperature of air at an inlet of the coke dry quenching boiler is controlled to 115 DEG C to 135 DEG C, and the temperature of actual running is controlled to about 125 DEG C and has a space of 10 DEG C from the maximum temperature, so the adjusting capability is high; and in addition, the quantity of circulating air is higher, so the temperature of the water entering the auxiliary coal saver is raised by about 8 DEG C in comparison with the temperature of the previous arrangement, the effect on the temperature of circulating air is little, and the running parameters of a coke dry quenching groove and the boiler are controlled within the specified range.

Description

technical field [0001] The invention relates to a new system for recovering waste heat of dry quenching coke, which belongs to coking engineering technology, and in particular to a recovery system for waste heat of dry coke quenching boiler blowdown water. Background technique [0002] At present, during the operation of the CDQ boiler, since some impurities are contained in the boiler feed water, they are continuously evaporated and concentrated in the boiler, so that the salt content in the boiler water gradually increases; in addition, adding chemicals to the boiler water will also make some products in the Deposition in the steam drum will deteriorate the quality of boiler water and steam. In order to maintain the steam quality within a certain range, it is necessary to blow down the boiler water. The usual sewage discharge methods include continuous sewage discharge and periodic sewage discharge. [0003] Continuous blowdown is to continuously discharge the water wit...

AI Technical Summary

Problems solved by technology

[0005] Under normal circumstances, the designed sewage discharge of the boiler is generally 1%~2% of the rated evaporation of the boiler. This part of the sewage is discharged from the sewage expansion tank into the sewage cooling pool and then directly discharged into the external drainage ditch. Not only is there heat loss, but also the sewage flow Steam will be generated in the passing place, and there will be certain safety hazards

Images