Method and device for removing solids from pickling liquid for cold-drawn and cold-rolled steel pipes

Abstract

The invention relates to a method and a device for removing solids from cold-drawn cold-rolled steel tube picking liquor. The method comprises the following steps: pickling a cold-drawn cold-rolled steel tube in a picking slot, carrying out coarse filtration on scrap-iron-containing pickling liquor with pH value being 2-5, removing solid particles substances such as scrap iron with particle diameter greater than 3mm, lifting the coarsely-separated solid-liquid mixture to a cyclone separator under action of an acid-resistant pump, throwing solid phase with greater specific gravity to the tube wall of the cyclone separator under action of greater centrifugal force, and exhausting solid phases in the acid liquor from a bottom flow opening. The device comprises a picking slot (1), a coarse-separating filter (2), a centrifugal pump (3), a cyclone separator (4) and a heat exchanger (5). According to the invention, the solid-liquid separating efficiency is high and the pressure loss is small. After using the combined solid-liquid separating equipment, abrasion on parts of the heat exchanger can be reduced and the service life of the heat exchanger is prolonged. The cyclone equipment is compact and reasonable in design, small in floor area, free of a back flushing part and low in operation cost.

Description

technical field [0001] The invention belongs to the technical field of solid / liquid separation, and relates to a method for removing solid particles such as iron filings produced in the production process of pickling steel pipes. More specifically, it relates to a method for desolidifying pickling liquid containing solid particles. The invention also relates to a desolidification device for pickling solution of cold-rolled and drawn steel pipes. Background technique [0002] The oxide skin on the surface of the steel pipe is usually produced in the process of cold drawing, cold rolling, forging or casting. Oxide scale is the oxide film of the metal, that is, the thin layer formed after the metal on the surface of the steel pipe is oxidized. The composition, structure and thickness of the oxide scale are determined by its formation conditions, such as the metal heating temperature, heating time and the atmosphere in which it is heated, and the properties of the oxide scale ...

AI Technical Summary

Problems solved by technology

[0007] Due to the above-mentioned problems in the prior art, the problem of scientific purification of cold-drawn and cold-rolled steel pipe pickling solution has not been solved so far, and it is far from meeting the needs of industrial production.

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