POTENSI MEMBRAN MIKROFILTRASI DAN ULTRAFILTRASI UNTUK PENGOLAHAN LIMBAH CAIR BERMINYAK

Abstract

Oily wastewater in the form of stable oil in water emulsion is found as one source of industrial wastewater in Indonesia. Conventional wastewater treatment has several limitations and is not able to achieve requirement for effluent standard. Nowadays, membrane microfiltration and ultrafiltration have been used for water purification as well as wastewater treatment. Studies on the application of microfiltration and ultrafiltration for wastewater have been conducted. However, the studies used real wastewater consisting complex compound. In this research a model of oily wastewater was used. The model of oily wastewater comprised an oil in water emulsion stabilized with a surfactant. By using this model, it is expected that analysis of membrane performance based on permeate flux and rejection can be conducted more comprehensively. This research used microfiltration and ultrafiltration membrane and the oily wastewater model was made by mixing Tween 80 with concentration of 2% with several types oil (vegetable oil, diesel oil dan cutting oil). The research is carried out in order to obtain wastewater and membrane characteristic as well as the influence of TMP, oily types and oil concentration on membrane performance based on permeate flux, COD and surfactant rejection.Based on this research characteristics of oily wastewater could be obtained. In general, increase of TMP resulted on higher permeate flux. By varying the oily type, it was found that the vegetable oil has the highest permeate flux, the effect of oil concentration on permeate flux in addition was depend on TMP. When the TMP was 1 bar, the increase of oil concentration produced lower flux. However at TMP of 2 bar, the permeate flux is independent on oil concentration. Experimental works using ultrafiltration resulted on 94,89 – 98,83% rejection of COD and 69 – 86% rejection of surfactant. Based on this research it is concluded that the ultrafiltration is capable to treat oily wastewater in the form of stable oil in water emulsion.