TINGKAT EFEKTIVITAS INSTALASI PENGOLAHAN LIMBAH CAIR HOTEL-HOTEL DI YOGYAKARTA

In the period of 2002 - 2003, a study was performed to assess the effectiveness of hotels' wastewater treatment plants in reducing  wastewater pollutant contents in Yogyakarta. There were 11 hotels surveyed, with 44 wastewater samples analysed in the parameters of BOD, COD, TDS, and detergent. The effectiveness degrees of the wastewater treatment plant in reducing pollutants in 2002 for the above parameters were 72.72% (BOD), 45.45% (COD), 90.90% (TDS), and 90.90% (detergent). While those for 2003 the degrees of pollutant removal were 45.45%, 27.27%, 81.81%, and 90.90% for the parameters of BOD, COD, TDS, and detergent respectively. It was meant that for the parameters of BOD, COD, TDS, and detergent, the effectiveness degree of the plants in 2003 for reducing the pollutants was decreasing as many as 27.27%, 17.73%, 9.09% and 0.0% respectively compared to those in 2002. Then, average level of the plant capability in reducing pollutant content in 2002 for the parameters of BOD, COD, TDS, and detergent were 72.28%, 66.5%, 74.7%, and 56.3% respectively, and those in 2003 were 56.7%, 59.5%, 74.5%, and 37.5% respectively, so the decreasing level of the plant capability for each parameters were 15.8%, 7.0%, 0.2%, and 18.8%. The average contents of BOD, COD, and TDS in outlet of the plants were 38.45 mg/l, 108.27 mg/l, and 20,7 mg/l respectively (2002), and 38.90 mg/l, 97.5 mg/l, and 34.09 mg/l respectively (2003). Improvement of the wastewater treatment plant performance especially was needed to reduce the parameters of BOD and COD.