Studies on decreasing Chemical Oxygen Demand (COD) and Phosphate on laundry wastewater using anaerobic and phytoremediation with algae plants (Hydrillaverticillata)

Abstract

In reducing the pollutant load contained in laundry wastewater such as COD and phosphate levels can be processed through anaerobic process and will be followed by phytoremediation methods. The purpose of this study is to reduce levels of COD and phosphate in laundry wastewater. This research was conducted in a laboratory scale with variations in plant mass. One type of aquatic plants that has the potential in phytoremediation waste management is algae (Hydrillaverticillata). The initial step in this research was carried out the seeding stage in anaerobic reactors with the aim of breeding bacteria with a suspended culture method which was marked by a decrease in COD with +10% fluctuations. Followed by the running stage in the anaerobic reactor until the reduction in COD ≥60% then, the stage of neutralization and acclimatization of plants with the aim of removing impurities in plants and adaptation of plants with microorganisms in wastewater. The last stage is the running stage of the phytoremediation process which is carried out by observing the value of COD and Phosphate in wastewater with variations in plant mass of 50, 100, 150, 200 and 250 grams in each reactor with contact time treatment for 7 days. Based on the analysis of COD parameters for each plant after anaerobic and phytoremediation processes on the last day the average efficiency of COD removal at 50 grams of plant mass is 86.34%, 100 gram plant mass of 81.81%, plant mass of 150 grams of 85.21%, 200 gram plant mass of 90.87% and 250 gram plant mass of 87.47% while the results of the analysis of Phosphate COD parameters for each plant the average removal efficiency of Phosphate in 50 gram plant mass is -25 %, 100 gram plant mass of -298.81%, 150 gram plant mass of -417.86%, 200 gram plant mass of -501.19% and 250 gram plant mass of -462.5%.