Treatment method of ammonia nitrogen wastewater

Abstract

The invention discloses a treatment method of ammonia nitrogen wastewater. The method comprises the following steps: contacting the ammonia nitrogen wastewater is contacted with air under an alkaline condition so as to enter an air stripping procedure for preliminary denitrification; transferring the preliminarily denitrified wastewater to an ion exchange column containing ammonia nitrogen adsorbing resin for deep denitrification, and absorbing NH3 gas generated in the air stripping procedure with hydrochloric acid solution or sulfuric acid solution, wherein, the ammonia nitrogen adsorbing resin used in the ion exchange denitrification procedure is aminocarboxylic acid chelating cation exchange resin loaded with copper ions; and NaOH is taken as a desorbent so as to regenerate the resin, and then stripping liquid returns to the air stripping procedure. By utilizing the treatment method of the invention, the defect of a simple air stripping method such as low efficiency in the case of low ammonia nitrogen concentration is overcome, and meanwhile the problem of worse treatment capability while treating the high-concentration ammonia nitrogen wastewater by a simple ion exchange resin adsorption method is solved; and by taking alkali as a resin desorbent instead of acid, drug consumption and treatment cost are reduced. The treatment method of the invention is simple in process, economical, efficient and environmentally friendly, and is applicable to treating the ammonia nitrogen wastewater.

Description

technical field [0001] The invention belongs to the field of environmental engineering and relates to a treatment method for ammonia nitrogen wastewater. Background technique [0002] Ammonia nitrogen is an important pollutant that causes water eutrophication and pollutes the environment. At present, in almost all polluted waters in China, ammonia nitrogen is one of the main pollutants. Water pollution, especially water eutrophication, has become an economic important factors for development. How to treat ammonia nitrogen wastewater efficiently and at low cost is an important problem faced by environmental workers. [0003] At present, the commonly used ammonia nitrogen wastewater treatment methods include stripping method, biological denitrification method, zeolite adsorption method and chemical precipitation method. The stripping method is to convert high-concentration ammonia-nitrogen into free ammonia under alkaline conditions, and use air (or steam) to transfer free a...

AI Technical Summary

Problems solved by technology

The problem with the biological method is that due to the slow growth of nitrifying bacteria and the long reaction time required, the ammonia nitrogen load in the treatment process is low and the treatment facilities are huge. Although the research on the new biological denitrification process has made some progress, it still cannot fundamentally solve the above problems

But there are the following problems: (1) directly use resin to absorb high-concentration ammonia nitrogen wastewater, the amount of resin is large, and the investment required is large; (2) hydrochloric acid or sulfuric acid is used as desorbent, and the resin working cycle includes: ammonia nitrogen adsorption→acid desorption→water washing → Alkali regeneration process, the process is more complicated, and it needs to consume acid and alkali at the same time, and the cost of chemicals is high, thus restricting the use of this method

Images