No abstract

In the seaweed processing industry to obtain quality products that are free of microorganisms, high concentrations of chlorine are used in the cooking process. Thus the wastewater from the cooking process still contains high concentrations of residual chlorine, where the wastewater when disposed of into the aquatic environment can cause pollution and damage of environmental. The aim of the research is the reduction of high concentrations of residual chlorine in seaweed wastewater using a combination process of aeration, heating and addition of Hypochlorous acid (HCl). The experiment was conducted by adding wastewater from the seaweed cooking process with HCl (1; 2; 3; and 4% v/v), aeration flowrate (1; 1.5; 2; and 2.5 Ls/minute) and heating temperature (35; 40; 45; and 50°C). Residual chlorine concentration was measured using the iodometric method. The experimental results showed that the maximum reduction of residual chlorine by 96.3% was obtained by adding HCl by 3%, aeration flowrate of 2.5 L/minute and heating temperature of 45°C.