Glyphosate wastewater treatment method

Abstract

The invention relates to an improvement of a method for treating wastewater generated during glyphosate production, which is characterized in that the improved method comprises the following steps: firstly, adding water to dilute the wastewater until the content of salt is less than or equal to 4%; adjusting the pH to 7.5-9.5; carrying out anaerobic biochemistry in the presence of drimophilousbacteria to destroy the structure of organics difficult to dissolve; adjusting effluent to acidity to carry out Fe-C micro-electrolysis reaction; adding alkali up to neutrality or alkalinity, adding drugs to coagulate and precipitate; adding oxidizer into effluent to carry out aeration strong oxidation reaction; and adjusting the pH of effluent to 7-9 to carry out aerobic biochemistry in the presence of drimophilousbacteria. In the invention, the anaerobic biochemistry, materialization and aerobic biochemistry treatment processes are adopted, thereby providing a process route which has simple and practical process and low cost and is high efficient and reliable, and simultaneously has dual effects on lowering treatment cost and improving treatment effect; and the treated effluent can reach the ''National Integrated Wastewater Discharge Standard'' (GB-8978-1996).

Description

technical field [0001] The invention is an improvement to the wastewater treatment method produced in glyphosate production, and in particular relates to a treatment method with simple process and low treatment cost. Background technique [0002] Glyphosate is mostly prepared from glycine, paraformaldehyde, and dimethyl phosphite as raw materials. Glyphosate products are obtained through condensation, hydrolysis, crystallization, and filtration. The filtered mother liquor is neutralized by alkali to recover the catalyst. The characteristics of the remaining wastewater are: The alkalinity is very high up to pH14, the COD concentration is high (≥30000 mg / L), the salt content is high, the total salinity is as high as 15%-20%, and contains refractory glyphosate, glyphosate, glycine, sub Phosphate and other organic substances are characterized by high alkalinity, high salinity, and high concentration, making them one of the most difficult organic wastewaters to treat. The tradi...

AI Technical Summary

Problems solved by technology

Multi-effect evaporation not only has high energy consumption and high processing cost, but it cannot be used when there is no good processing method in the industry, and it will be solid waste after steaming, which needs to be treated separately, which increases the processing cost; membrane separation has the following disadvantages : First of all, besides glyphosate, glyphosate wastewater also contains a large amount of glyphosate, organic by-products and phosphite. The glyphosate concentrate obtained by membrane filtration and concentration cannot remove these substances, so it is not suitable for direct recycling. For production, it is very difficult to prepare glyphosate water with a concentration of more than 30%, and even if it is formulated, the cost is relatively high; secondly, the treatment of the concentrate after membrane filtration is still a problem; moreover, due to direct filtration, membrane Severe pollution, frequent membrane flushing and replacement lead to high treatment costs, unacceptable for practical applications

After adding alkali to neutralize the recovered catalyst, it will be highly alkaline alkaline glyphosate wastewater. Adding acid to adjust the pH to 3-4 will not only consume a large amount of acid, but also cause serious chloride ion corrosion, which requires high equipment; secondly, for glyphosate Phosphine wastewater components, direct Fenton and catalytic oxidation are not very effective in cracking refractory organic matter, which affects subsequent biochemical treatment

The above prior art shows that the low-cost treatment of glyphosate wastewater is still a difficult problem