Ragn-Sells is planning to build a new production facility for washing fly ash and extracting salts at Högbytorp, northwest of Stockholm. Sweco is responsible for the design of the facility. The plant will contain full recirculation solutions for both waste management and water purification in the salt extraction process. When in operation, it will process 130 kilotons of fly ash per year. The plant is expected to be operational in 2021.
Assignment: Design of a salt recovery facility
Area of operation: Structural engineering, heating, ventilation and electrical engineering, architecture, water and environment, geotechnical engineering, acoustics, visualization, energy calculations, fire protection engineering and risk assessment
Location: Högbytorp, Stockholm
Fly ash is a byproduct from the incineration of waste. It contains, among other things, heavy metals and chlorides. In the new recovery plant, fly ash will be washed and four different types of salts will be recovered; potassium chloride, sodium chloride, calcium chloride and ammonia solution. As an additional benefit the ash residue that remains after washing is clean. The clean ash can be used, for example, to replace limestone used the cement industry. This recovery process allows salts and ash residue to be returned to the community. Additionally, all the cleaning water in the process is purified and reused. This new salt recovery process is an exciting milestone in the goal for sustainability. Sweco will deliver comprehensive design services and project management.
Sweco's assignment consists of designing the new facility and contributing with broad set of expertise in structural engineering, mechanical and electrical consultants, architects, water and environmental consultants and geotechnical consultants.