Utilization of LD slag from steel industry for the preparation of MF membrane

This work is focused on utilizing the solid waste generated from steel industry for the fabrication of porous ceramic membrane from Linz Donawitz (LD) slag. Membranes were fabricated using uniaxial method sintered at three different temperatures like 650 °C, 850 °C and 950 °C. Membranes fabricated with raw LD slag gave a highly basic filtrate. In contrast with this issue, LD slag was modified using acetic acid and CO₂ purging to convert calcium oxide which is present in the slag to calcium carbonate. The membranes fabricated from modified LD slag showed a filtrate pH of 8.4 and 8.5. Porosity, pore size distribution, flexural strength, chemical stability was determined and pure water flux experiments were conducted to evaluate the efficiency of the prepared membranes. Considering the raw materials cost, the cost of the fabricated membranes was estimated in the range of 32.55-55.7 USD/m². This work gives a potential path to develop microfiltration ceramic membrane with, high porosity and great quality in terms of strength and chemical stability. The fabricated membranes were utilized in a hybrid technique (flocculation followed by microfiltration) for the treatment of cold roll mill (CRM) wastewater generated from steel industry. Use of LD slag for the fabrication of ceramic membrane is not only an appealing option towards the commercialization of membrane, yet also great option to reduce the solid waste which is dumped to the environment.