Feasibility Study on A Novel Waste Heat Recovery Process of Industrial Waste Salt Based on High Temperature Melting Dry Method

School of Metallurgy, Northeastern University, No. 11, Lane 3, WenHua Road, HePing District, Shenyang, 110819, Liaoning, PR China

^* xiehq@smm.neu.edu.cn

Abstract

Industrial waste salt is mainly produced by industrial production processes of pesticides, drug synthesis, printing and dyeing, as well as solid-liquid separations, concentration and crystallization of solution, and sewage treatment, etc. At the present stage, the annual output of waste salt in China has exceeded 2.0×10⁷ tons and the high-temperature melting method is considered to be a promising treatment method, but there are problems such as molten salt adhesion and agglomeration, unused high-temperature sensible heat, and waste of water resources. A novel process for waste heat recovery by high temperature melting dry method is proposed in this paper, using a combination of centrifugal granulation and waste heat recovery to dispose high-temperature molten salt and effectively recover heat. Through thermal equilibrium analysis and calculation, the waste heat recovering efficiency of the waste heat recovery using the novel process can reach up to 98%. Taking the annual treatment of 100,000 tons of waste salt as an example, the benefits of effective heat recovery converted to standard coal could be approximately 5 billion. While efficiently utilizing waste heat resources, the novel process brings considerable economic benefits to enterprises, has good industrial application prospects, and helps to advance the process of national hazardous waste solid waste treatment.