Characteristics of Concrete Waste Water and Progress of On-Going Treatment

Abstract

The purpose of this study is the examination of the properties of waste water obtained from a ready-mixed concrete plant and its utilization potential as mixing water for concrete production of the batching plant from Great Wall industry, Sagaing Division, Myanmar. The fact that wastewater has detrimental effect on durability of concrete structures is not disputable. Thus durable concrete will retain its original form, quality, and serviceability when exposed to its environment. Samples of waste water from several points of a water recycling process from this ready-mixed concrete plant were examined for their chemical properties (CI; SO₄^{2 -}, alkalis, total solids, pH) and compared with the specifications applied for concrete mixing water. Also samples of dry sludge powder form the water-recycling process tank were taken and tested for their chemical composition, particle size distribution, and mineralogical composition and thermo gravimetrical results. The water samples were examined for their behavior in concrete specimens with and without admixtures and also for their effect in water demand and setting times in cement pastes. This paper reviews the degradation mechanism of wastewater on ready-mixed concrete structures with a view to finding what needs to be done to salvage these structures. It is obvious that the results of this investigation contribute to the protection of the environment from hazardous waste water disposal and the ready-mixed concrete industry from fresh water costs and any additional cost for buying and conserving an unnecessary complicated water-recycling system.