Effects of Spent Wash Water on the Properties of Concrete

In construction industry, concrete is most widely used construction material. About 5 billion cubic yards of concrete are used each year; annual production is about two tons per person on the plane. As per provision of IS 10262-2009, 186 L water is required for one cubic meter of concrete. On an average 150 L water is required for 1 m3 of concrete. The distillery spent wash is a dark coloured, acidic (pH < 4.0), high BOD liquid consisting primarily of biodegradable organics and some inorganic constituents. Spent wash is a rich source of organic matter and nutrients like nitrogen, phosphorus, potassium, calcium and sulphur. The high concentrations of some substances of waste water could raise concerns about the potential for corrosion and sulphate attack in reinforced concrete structures, mostly in geopolymer concrete as it consist compound chemicals which reacted with the water. The main intention of present study is to investigate the effects of spent wash water on the plastic and hardened properties of conventional concrete and geopolymer metakaolin concrete. In the present study, the different samples of spent wash is collected from inlet and outlet of Effluent treatment plant as well as contaminated sources of water, it was found that the standard consistency of cement sample with waste and tap water is 32% and 31% respectively. But, the initial setting time of cement by using contaminated water and tap water was noted as 58 min and 80 min respectively, and the final setting time was found quite similar for both cases of tested samples. The soundness of cement by using contaminated and tap water is varied but found within permissible limits of IS 1489:2015. The workability was improved with increased percentage of spent wash water replaced to tap water up to 20% in concrete, but more increase the percentage of spent wash water in concrete have recorded failure of slump. One of the major observations related to the hardened concrete is that the replacement of spent wash water up to 15% of tap water has increases the compressive strength of concrete up to 20% than the normal tap water concrete, but there was reduction in compressive strength of concrete by 6% when spent wash replacement was 20%. This was considered as datum for comparison in further studies on effects of spent wash on geopolymer concrete.