Water-saving type strip steel pickling line and method capable of recycling hydrogen and without pumping and discharging acid mist

Abstract

The invention relates to a water-saving type strip steel pickling line and a method capable of recycling hydrogen and without pumping and discharging acid mist. A steel strip is immersed in a water tank, and the lower ends of the end sealing plates arranged close to a water tank pressure roller in the acid tank direction and in sealed connection are inserted into the water in the water tank; the steel strip is immersed in a cleaning tank, the upper liquid surface of the immersed section in the acid tank direction and the upper plate and side plate of an overflow water sealing component form a pure space, and a water curtain is arranged in the space and mixed with the acid surface on the contact surface; two kinds of port sealing acid mist structures can totally seal the acid mist generated by the acid tank and permeating in the port to prevent escape. A 'wet-wire cluster type' dynamic sealing structure can totally mix the acid mist leaking from the gap formed by the roller diameter passing through the hat wall while the debugging is easy and the rotation resistance against the roller diameter is low. The pickling line is designed into a top hat-shaped height space; and according to the characteristics that the gas-state hydrogen and the acid mist generated by pickling are in great weight difference and the two are incompatible, the hydrogen and acid mist in the hat are at different areas according to the height, the hydrogen is recycled from the upper end of the top hat, and the middle and lower ends of the top hat are acid mist condensation areas.

Description

technical field [0001] The invention relates to a water-saving strip steel pickling line and method with recyclable hydrogen without exhausting acid mist, and belongs to the field of strip steel pickling equipment manufacturing. Background technique [0002] At present, before using conventional hot-rolled steel strips as raw materials for cold rolling, descaling operations are generally required. The thicker oxide skin removal method commonly used now, the general process is to repeatedly bend to peel off or loosen the oxide skin, and then pickle; or use mechanical methods. [0003] During pickling, more scale is peeled off by the hydrogen gas generated by the reaction between acid and steel base, so the effect of scale removal is good, and it is a method commonly used in the cold-rolled strip industry so far. The process characteristics of the pickling method, the acid needs to be heated to about 70 degrees Celsius (depending on the acid), and the pickling effect is good....

AI Technical Summary

Problems solved by technology

[0004] Background Art The disadvantages of strip steel pickling line are as follows: firstly, by configuring a high-power exhaust fan, all the acid mist generated can be sucked in theory, but at each point of the inlet and outlet cross-section, it is in the same direction as the direction of strip steel travel. If the negative pressure formed by the T-shaped exhaust fan is different during operation, it is actually difficult to avoid the escape of acid mist; the high-power exhaust fan consumes more acid and electricity, and the production cost is higher; Atmospheric pollution is a common problem; the second is that acid mist is the gaseous form of acid liquid, and it is a waste of acid liquid to suck it; the power consumption of exhaust fan, acid mist treatment tower power consumption, consumables, water consumption, acid mist treatment tower There are also secondary pollution problems; the third is that a considerable amount of hydrogen generated by the pickling chemical reaction is directly discharged into the atmosphere, resulting in energy waste; and hydrogen is a suitable protective atmosphere for heat treatment of strip steel or high-quality energy that can be used for acid heating. ; The fourth is to use extensive leaching, which consumes a lot of water; the amount of water that needs to be treated in an environmentally friendly manner is large

The deficiencies of the existing overflow pickling for wire rods are: first, part of the condensed acid liquid flows into the water seal tank, and a considerable amount of acid mist is fused with the water curtain, which is not conducive to saving acid and water; second, the hydrogen has not been recovered , which is also not conducive to acid mist condensation

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