A treatment method for steel rolling oily sludge

Abstract

A method for treating oily sludge from steel rolling. First, the oily sludge from steel rolling is mixed with quicklime powder, and the proportion of quicklime powder added to the oily sludge from steel rolling is 2.5 to 7.5% by weight; then put into a rotary kiln reactor for low-temperature gasification Oil treatment, in which the temperature is 300-500°C, the air excess coefficient is 0.2-0.8, and the reaction time is 10-30 minutes; then the combustible flue gas discharged from the rotary kiln reactor enters the secondary combustion chamber for combustion, and the hot flue gas produced is returned to the Enter the rotary kiln reactor as the external heat source of the rotary kiln reactor, and the oily sludge residue from steel rolling after deoiling is used as the raw material for ironmaking and sintering. The method of the invention has the advantages of low energy consumption, low pollutant discharge, and the deoiling residue can be returned to production and utilization within iron and steel enterprises.

Description

technical field [0001] The invention relates to a waste treatment method, in particular to a treatment method for steel rolling oily sludge. Background technique [0002] There are two main sources of oily sludge from steel rolling: one is the sludge generated by direct cooling of circulating wastewater in processes such as hot rolling, preliminary rolling, and thick plates, which is treated by cyclone sedimentation and then by advection sedimentation; The effluent after precipitation is filtered by the filter and then reused. The laminar flow cooling wastewater of the strip steel is filtered and reused after precipitation. The above two filters backwash the effluent and precipitate the sludge; The characteristics of iron oxide, generally, the water content is 10-20%, the oil content is 1-10%, and the total iron content is 30-55%. The main treatment and disposal methods of steel rolling oily sludge are: [0003] 1) landfill, final disposal but there are shortcomings of occ...

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Problems solved by technology

[0003] 1) landfill, final disposal but there are shortcomings of occupying land and waste of iron resources;

[0004] 2) Incineration, the oil (organic matter) removal effect is good, but it has the disadvantages of high energy consumption and the need to deal with the exhaust gas;

[0005] 3) Low-temperature distillation can recover oil and iron resources, but oil purification is more complicated and costly, and is suitable for the treatment of high oily sludge;

[0006] 4) Solvent extraction can recover oil and iron resources, but there are long processing procedures, troublesome waste solvent reuse and solvent safety issues;

[0011] 3) Back-coking requires drying and coal-mixing pretreatment, and because of the high iron content, it has negative effects on coke gas permeability and coke oven refractory bricks;

[0012] 4) Back to sintering, during the sintering process, the oil will volatilize and enter the flue gas of the main flue, which will have a negative impact on the safety of the electrostatic precipitator;

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