Study on treatment and recovery of ammonia nitrogen wastewater

Title : Study on treatment and recovery of ammonia nitrogen wastewater

Abstract:

The production of nitric acid, ammonium nitrate, compound fertilizer, and other products, lead to producing lots of highly concentrated wastewater with nitrate nitrogen and ammonia nitrogen, which will pollute the environment and waste useful resource if discharged directly. A multi-stage electrodialysis and reverse osmosis wastewater treatment system was designed and installed by the company in 2020. Ammonia and 58% diluted nitric acid react to form ammonium nitrate throughout the production process. Ammonia nitrogen-containing steam will be created during the evaporation and concentration of ammonium nitrate, and the steam will then condense into industrial effluent that contains ammonia nitrogen. After treatment, the wastewater's ammonium nitrate content was reduced from 50g/L (20–70g/ L) to within 10mg/L, its ammonia nitrogen content was reduced from 93.6g/L to within 3.5mg/L, and its conductivity was decreased from 70ms/cm to 3.4s/cm, allowing it The ammonium nitrate concentration in the concentrated water produced by electrodialysis and reverse osmosis can reach more than 100g/L and can be used again in the ammonium nitrate production system since the discharge water satisfies the discharge criteria. The treatment system can recover around 1600 t of ammonium nitrate and 127,000 t of fresh water yearly with a reuse rate of about 80%, which has significant positive effects on both the economy and the environment. In this work, the pre-treatment, multistage electrodialysis, and reverse osmosis methods for treating ammonia nitrogen wastewater from chemical industries were studied. The findings of the experiment indicated that: The removal rates for ammonium nitrate, ammonia nitrogen, and desalination are all above 99.8%, 99.9%, and 95%, respectively. The process has the advantages of short flow, simple operation, convenient maintenance, and easy mechanization and automatic control.

Audience Take Away Notes

• This paper shows the treatment and recycling of ammonia nitrogen wastewater in a chemical enterprise
• This paper provides reference for the study of industrial wastewater treatment, other faculty could use the result to expand their research or teaching
• Economic analysis of process operation is carried out

Biography:

Prof. Xueli Su graduated from Nanjing University of Science and Technology, China with a B.E. in chemosynthesis and received MS in 2000 at Hubei University. She joined the research group of Prof. Wu Cai-ying at Wuhan University, did research in flavor compounds in beer and studied techniques in solid phase micro-extraction in 2003, and was supervised by Dr. Tom Brenna in 2014, studied polyunsaturated fatty acids at Cornell University as visiting scholar. Her research group has been funded by the local government and these grants have supported work in environmental and green chemistry and published more than 40 research articles in journals.