Method for processing nitrobenzene and aniline waste water

Abstract

The invention provides a method for treating nitrobenzene and aniline waste water. The invention treats waste water mainly through immobilized microorganisms - an anaerobic biofilter (I-AF) and immobilized microorganisms - a biological aerated filter (I-BAF); wherein: the waste water is homogenized through a regulating tank and then enters a sedimentation tank to remove suspended substances (SS) in the waste water by putting into polymeric iron or polymeric aluminum for coagulation reaction; and the yielding water reach the up-to-standard discharge after entering a three-grade I-AF reactor and a four-grade I-BAF reactor for the further treatment. For detailed method and steps, please see the description. The method has advantages that the biological treatment improves the toxin immunity of microorganisms by adopting the immobilized microorganism technique, thereby realizing the high efficient biologic removal to poisonous harmful substances such as high concentration nitrobenzene and aniline, reducing the treatment costs and realizing the up-to-standard discharge of waste water. The purposes of the invention are applied to the treatment of wastewater containing nitrobenzene and aniline, as well as the treatment to high concentration organic waste water and the like.

Description

technical field [0001] The invention belongs to the field of industrial waste water treatment, and in particular relates to a method for waste water containing pollutants such as nitrobenzene and aniline in polyurethane and its raw material industry. Background technique [0002] Nitrobenzene compounds are a class of highly carcinogenic and mutagenic toxic organic pollutants, which are listed as environmental priority pollutants by the U.S. Environmental Protection Agency. They are stable in structure, difficult to decompose and transform, and are refractory to biodegradable compounds. Aniline is the same It is highly toxic to humans and other organisms, so many countries have strictly restricted the emission standards of aniline and nitrobenzene. In view of the high toxicity of nitrobenzene and aniline, traditional biological methods are less effective in treating these pollutants, and it is difficult to guarantee discharge standards. At present, nitrobenzene wastewater is...

AI Technical Summary

Problems solved by technology

In view of the high toxicity of nitrobenzene and aniline, the effect of traditional biological methods on treating these pollutants is poor, and it is difficult to ensure that the emissions meet the standards

At present, nitrobenzene wastewater is mainly converted into aniline by iron-carbon internal electrolysis, and then biologically treated; This method mainly converts nitrobenzene into aniline, and then removes it by ferric hydroxide adsorption. The remaining nitrobenzene and aniline are mainly oxidized by Fenton’s reagent. Sludge disposal is still a difficult problem; the most widely used method is to use activated carbon or carbon fiber adsorption to process nitrobenzene (Chinese patent application number 200610151164, application number 00114476, application number 96117148). It is difficult to treat the regenerated liquid; there is also a combined treatment method of high temperature and high pressure oxidation technology and biological treatment, which also has the problems of high treatment cost and unstable treatment effect; some people also use carbon tetrachloride or benzene extraction to process nitroaniline Wastewater (Chinese Patent Application No. 95117037), this method is applicable to the treatment of high-concentration nitrobenzene, aniline waste water, and its main shortcoming is in addition to the high processing cost, complex operation control and poor safety, the waste water after extraction cannot reach the standard, Still needs to be dealt with

The Chinese patent with the application number 200410065840 reports that the biological method is used to treat nitrobenzene and aniline wastewater, but it is suitable for treating low- and medium-concentration wastewater, and microorganisms need to be added every day, and the treatment cost is high

Biological methods are used to treat high-concentration nitrobenzene and aniline wastewater, which has not been reported so far

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