Method for heating acid washing solution

Abstract

The invention discloses a method for heating acid washing solution. The method comprises: (1) the acid washing solution in an acid washing tank 1 flows back into an acid circulation tank 2, is filtered through a filter 3 and is pumped into a heater 6 by an acid-resistant pump 4 through an inlet 5 of the heater, the heated acid washing solution is pumped into the acid washing tank 1 through an outlet 7 of the heater to form circulation, and the circulation is repeated in the way; (2) heating steam enters through a steam inlet 8 and is discharged through a steam outlet 9, so that the acid washing solution is kept at normal technological temperature all the time; and (3) acid mist which is generated during the acid washing process is concentrated through a mist collector 10 under the action of a mist exhaust fan 12 and enters an acid mist purification system 11 to be purified, and the mist which meets the emission standards is discharged to the atmosphere 13 through the mist exhaust fan 12. By the method, heat exchange is indirectly realized, the acid washing solution cannot be diluted, excessive acid mist is not generated, the acid mist cannot be leaked during the heat exchange process, and the heating process of the acid washing solution and the temperature of the acid washing solution can be automatically controlled through adopting a heat exchanger.

Description

technical field [0001] The invention relates to an auxiliary method for the production process of the cold rolling industry, in particular to a method for heating a pickling solution, which is suitable for the pickling process of hot-rolled strips in the cold rolling industry. Background technique [0002] At present, before the cold rolling of the hot-rolled carbon structural steel strip, it is necessary to clean the oxide scale on the surface of the hot-rolled strip through a pickling process. In the pickling process, sulfuric acid pickling mainly relies on mechanical stripping to remove scale; hydrochloric acid pickling mainly relies on dissolution to remove scale. In order to speed up the pickling speed, improve the pickling quality, and adapt to modern large-scale production, it is necessary to heat the pickling solution to a certain temperature. The higher the temperature of the pickling solution, the stronger the activity and the shorter the pickling time. The sulfur...

AI Technical Summary

Problems solved by technology

The pickling solution is generally heated by steam. For example, when steam is used for direct heating, the pickling solution is continuously diluted due to the condensed water of the steam entering the pickling tank, which reduces the pickling speed; direct heating with steam produces a large amount of acid mist. The burden on the acid mist purification system is increased; the pickling solution is replaced too quickly, which increases the load of the acid regeneration system; direct heating of steam can easily cause the acid mist to escape, causing corrosion of equipment and steel structures in the workshop

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