Treatment method of steel rolling oily sludge

Abstract

Disclosed is a treatment method of steel rolling oily sludge. Firstly, quicklime powder is added into the steel rolling oily sludge for mixing, wherein the weight ratio of the quicklime powder in thesteel rolling oily sludge is 2.5-7.5%; secondly, the mixture is put into a rotary kiln reactor for low temperature gasification and de-oiling treatment, wherein the temperature is 300-500 DEG C, the excess air coefficient is 0.2-0.8 and the reaction time is 10-30 min; and finally, combustible flue gas discharged from the rotary kiln reactor enters a secondary combustion chamber for combustion, generated hot flue gas returns to the rotary kiln reactor as an external heat source of the rotary kiln reactor, and de-oiled steel rolling oily sludge residues are used as raw materials of ironmaking sintering. The method has advantages of low energy consumption, low pollutant discharge and internal reuse of the de-oiled residues in 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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