Permanent hardness in water is mainly due to the presence of the chlorides, nitrates and sulphates of calcium and magnesium. One third of Maharashtra state has such hardened water in the form of ground water. High level of hardness of the soil turns rain water into hard ground water. This hardness in ground water cannot be removed easily using conventional techniques such as filtration, boiling, precipitation, etc. on large scale in order to meet the industrial and agricultural demands. So despite the adequate availability of water, people from these regions are unable to use it for any application in domestic, agricultural and for industrial purpose, creating a virtual drought like situation. Hence, the removal of hardness or softening of water to usable limits is the prime requirement for Maharashtra state. Considering this overall situation the primary objective is to develop, a novel and feasible approach to treat that saline (i.e. hard) water using micro algae as an emerging era in the technological domain. Hardening of water takes place due to dissolution of salts as it passes through the soil. This hard water is pumped out from the ground using manual and electrical pumps. This water can be collected in storage tanks, artificial lakes, wells or other possible stationary form of water reservoirs. The hardness of this water can then be removed significantly by growing microalgae in it. Hard water acts as a suitable media for growth of microalgae. Microalgae requires carbon source like organic pollutant or inorganic carbon source and inorganic nitrogen source. Hence in this case the dissolved salts in hard water act as the source of carbon, and are metabolised by the algae; thus reducing the hardness. Another advantage of this approach is that, being micron size, microalgae do not block the pipelines by growing or sticking to the walls of pipes. Also, this microalgae after treatment of water can be easily separated by simple filtration, or can even be disrupted using hydrodynamic cavitation if required for the recovery of valuable lipids. In case of agricultural use, there is no need for the removal of the algae, as it can act as a biomass/fertilizer and an additional carbon source. Secondary Objective: Even though salts from soil can be removed by plantation of particular species (e.g. Taag, Mulbery plants  etc.). It will also increase the soil fertility for other crops. Conclusion: The hardness can be removed from ground water by using algae and from soil by plantation
We are a team of 5 students pursuing PhD in Institute of Chemical Technology Mumbai. We are expert in waste water treatment, sea water using advanced oxidation techniques with aid of hydrodynamic cavitation. We are now focusing on biological systems for wastewater treatment with bacteria, algae, enzymatic systems. we are proposing a greener method combination of hydrodynamic and biological system of wastewater treatment.