Naphthalene Sulfonic Acid Wastewater Extraction Project

This chemical plant in Ningxia discharges sodium naphthalenesulfonate wastewater during production. The content of sodium sulfate in the wastewater is 16-19%, and the content of naphthalenesulfonic acid is 2-4%.

The customer requires that the naphthalenesulfonic acid in the wastewater be removed, and the content of naphthalenesulfonic acid in the treated wastewater is required to be less than 0.1%.

The water quality of DSD Acid Wastewater of the chemical plant is as follows: cod is 27040mg / L, BOD5 is 521mg / L, nitro content is 17259mg / L, salt content is 14%, brown black, and pH value is less than 1.

The technical process provided by Tiei as following:

Firstly: Adjust the pH of naphthalene sulfonic acid wastewater to about 0.5, reduce the naphthalene sulfonic acid and sodium naphthalene sulfonate in the wastewater to the organic form of naphthalene sulfonic acid, and meet the optimal pH value for extraction;

Second：Carry out continuous countercurrent mixing of the selected complex extractant and the wastewater, and the naphthalene sulfonic acid will react with the extractant and transfer to the extractant to complete the extraction process;

Last：The loaded extractant (the extractant complexed with naphthalene sulfonic acid) generates sodium naphthalene sulfonate under the action of the alkaline solution and enters the alkaline solution to complete the reverse extraction process.

After continuous multi-stage stripping of the loaded organic phase, the regenerated extractant can be recycled to reduce the cost of wastewater treatment.

CWL-M centrifugal extractor applied in this extraction production project, after the treatment of naphthalene sulfonic acid in wastewater, the complex extractant is selected as the extractant. After two-stage cross flow extraction, the COD in the residual liquid is 1470mg / L, and the removal rate is 94.6%, meeting the requirements of customers. At the same time, the content of sodium sulfate remained unchanged after extraction.

Using Tiei centrifugal extractor , the color of the treated wastewater is almost colorless, and it can be directly sent to the next section for treatment. It has solved a lot of problems for us. Much appreciated to Zhengzhou Tiei.