Iron based coagulants are widely used in the purification of municipal and industrial wastewater and in sludge conditioning and dewatering at municipal wastewater treatment stations, food processing, tanning and metal industries. Using iron-based coagulants helps to remove sulphide origin odours, at the same time reducing the load of phosphates and biological oxygen demand at biological wastewater treatment plants, which entails reduction in air flow in the aeration tanks and therefore power consumption at blower pumps and aerators.