Inorganic Chemicals Industry ›› 2025, Vol. 57 ›› Issue (4): 105-110.doi: 10.19964/j.issn.1006-4990.2024-0269

• Environment·Health·Safety • Previous Articles     Next Articles

Study on optimization of COD and fluoride removal on waste salt carbonization process by response surface method

LI Jun(), ZHOU Zhaoan, LIU Xiaowen, MAO Anzhang, ZHOU Aiqing   

  1. Guangdong Feinan Resources Recycling Co.,Ltd.,Zhaoqing 526233,China
  • Received:2024-05-13 Online:2025-04-10 Published:2025-04-21

Abstract:

In order to reduce the energy consumption of COD removal by carbonization of waste salt,metal catalyzed organic cracking technology was used.The process of COD removal by Cu2+ catalyzed carbonization of waste salt was studied.The effects of Cu2+ dosage,reaction temperature and reaction time on COD removal in the carbonization process of waste salt were investigated.The response surface method was used for modeling optimization and verification.The results showed that the effect of COD removal by Cu2+ catalyzed carbonization of waste salt was obvious,and higher COD removal rate could be obtained at lower temperature.When the catalyst was not added,the COD removal rate of the waste salt carbonized at 550 ℃ was 90.45%.After adding the catalyst,the COD removal rate of the waste salt carbonized at 350 ℃ could reach 92.20%,so the temperature reduction effect was remarkable.The significant factors affecting COD removal rate from high to low were Cu2+ dosage,reaction temperature and reaction time.The response surface method was used to optimize the mathematical model established by waste salt carbonization.The fitting value was in good agreement with the verification test results.The optimal process parameters after optimization were as follows:the amount of Cu2+ was 0.4%,the reaction temperature was 450 ℃,and the reaction time was 0.7 h.At this time,the predicted COD removal rate was 98.53%.Through three experiments,the average COD removal rate was 98.55%,which was 0.02% different from the model,indicating that the optimization conditions were accurate and reliable.

Key words: waste salt, low temperature carbonization, removal of COD, catalytic pyrolysis, response surface method, Cu2+

CLC Number: