Management and sustainable utilization of processing wastes from ready-mixed concrete plants in construction: A review

This review focuses on the source, classification and management of the processing wastes from ready-mixed concrete (RMC) plants and their potential reutilization. In recent years, washing-out systems have been adopted at many concrete batching plants. Depending on reclaiming systems such as aggregate and water reclaimers, the wastes generated are classified as reclaimed aggregates, concrete slurry waste, wastewater and reclaimed water. Although the potential to reuse these wastes has attracted lots of interest, the respective principles and methods of treatments have only been reported in discretely, and sometimes inconclusive manners. The management challenges such as low re-usage rate, poor product performance, increasing cost and strict local regulations obviously limit their sustainable utilization. In order to minimize the dispose of the processing wastes from the RMC plants, the installation of both mechanical aggregate and water reclaiming systems are found to be necessary. All kinds of processing wastes can then be reused in producing different low carbon footprint products in order to improve the sustainable development of the RMC industry.