TINGKAT PENURUNAN KADAR BIOLOGICAL OXYGEN DEMAND (BOD) DAN CHEMICAL OXYGEN DEMAND (COD) LIMBAH CAIR INDUSTRI TAHU OLEH EFFECTIVE MICROORGANISM 4 (EM-4)

Abstract

Nowadays, there are many tofu industries doing their activity in public settlement. This industry is very related to environmental problems because it produce organic waste, so it can increase the Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) level. One of the alternative liquid wastes processing of tofu industry is by ferment tofu’s waste with microbe using Effective Microorganism 4 (EM-4). The purpose of this research is to know the difference of Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) level in tofu industry’s liquid waste before and after adding Effective Microorganism 4 (EM-4). This research is an experimental research with True Experimental Design. This research has control group and experiment that is the independent variable of the research. The control group is the sample water without Effective Microorganism 4 (EM-4), the first experiment group (X1) is added 4 ml/l of Effective Microorganism 4 (EM-4), the second experiment group (X2) is added 6 ml/l of Effective Microorganism 4 (EM-4), and the third experiment group (X3) is added 8 ml/l of Effective Microorganism 4 (EM-4). The result of this research showed that there is a significant difference in 4 of experiment group. The most effective EM-4 capability in decreasing Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) level is by adding 8 ml/l of Effective Microorganism 4 (EM-4).