ABSTRAKLimbah cair tahu dari industri tahu di Kabupaten Bandung Barat memiliki kandungan senyawa organik yang tinggi. Salah satu sistem pengolahan air limbah yang dapat dilakukan secara efektif adalah Sequencing Batch Reactor (SBR). Tujuan dari penelitian ini adalah untuk mengetahui peforma terbaik SBR dalam meningkatkan efisiensi pengolahan limbah cair tahu. Pada penelitian ini dilakukan pembibitan (seeding), aklimatisasi, dan sistem SBR dengan tahapan variasi kecepatan pengumpanan. Kecepatan pengumpanan SBR pada saat pembibitan (seeding), aklimatisasi, dan running 1 sebesar 200 ml/hari dan sebesar 400 ml/hari pada saat running 2. Hasil penelitian ini memperoleh penurunan konsentrasi COD terbaik dari 8.000 mg/L menjadi 96 mg/L diperoleh pada running 1 dan penurunan konsentrasi COD dari 8.000 mg/L menjadi 160 mg/L diperoleh pada running 2. Efisiensi tertinggi yang dihasilkan adalah 98,8% pada running 1 dan 98% pada running 2.Kata kunci : Limbah cair tahu, Sequencing Batch Reactor (SBR), Kecepatan Pengumpanan ABSTRACTTofu wastewater collected from the tofu industries in West Bandung Regency has a high organic content. One of the wastewater treatment systems that can be applied effectively is the Sequencing Batch Reactor (SBR) system. The purpose of this study was to find out the best performance of SBR in improving the efficiency of tofu wastewater treatment. This study conducted seeding, acclimatization, and SBR system that varied the feeding rates to find optimum value. The SBR feeding rate at the times of seeding, acclimatization, and running 1 amounted to 200 ml/day and amounted to 400 ml/day at the time of running 2. The results of this study were the best reduction in COD concentration from 8,000 mg/L to 96 mg/L obtained in the first running and reduction in COD concentration from 8,000 mg/L to 160 mg/L obtained in 2nd running. The highest efficiency produced was 98.8% on the first running 1 and 98% obtained from the 2nd running.Keywords: Tofu Wastewater, Sequencing Batch Reactor (SBR), Feeding Rates

Di Indonesia, khususnya di sekitar Politeknik Negeri Bandung, sebagian besar sumber air berasal dari air tanah. Air tanah di lingkungan Politeknik Negeri Bandung memiliki pH asam (< 6), coliform > 2.400, dan colitinja positif. Proses pemanasan air kurang efektif untuk mengolah air tanah karena memerlukan waktu yang relatif lama, energi besar, dan tidak dapat meningkatkan pH air agar memenuhi standar air minum sebagaimana tercantum dalam Permenkes Nomor 492/MENKES/PER/IV/2010. Untuk mengolah air tanah di lingkungan Politeknik Negeri Bandung, telah dibuat alat pengolahan air minum portabel dengan menggunakan konsep aliran dead-end filtration. Membran yang dipakai merupakan membran hollow-fiber, berjenis membran ultrafiltrasi berbahan dasar PVDF (Poly Vinylidene Flouride), ukuran pori 0,1μm, panjang membran 15cm, jumlah membran sebanyak 148 buah, dan dapat dioperasikan pada daya isap normal manusia.  Permeat yang dihasilkan sesuai dengan standar PERMENKES No. 492/MENKES/PER/IV/2010 dari parameter fisika, kimia, dan biologi. Lifetime membran diamati melalui jumlah permeat yang dihasilkan dari awal pemakaian membran hingga membran tersebut rusak. Lifetime pada alat pengolah air minum portabel ini adalah 38,879 L. Pengolahan air tanah menggunakan alat ini  dapat menaikkan pH sebesar 12,78%, menurunkan konduktivitas sebesar 39,31%, dan menurunkan Total Dissolved Solid (TDS) 13,72%. Dari segi ekonomi, penggunaan alat ini dapat menghemat biaya 50% dibandingkan dengan pembelian air minum kemasan 600 ml.In Indonesia, especially around the Bandung State Polytechnic, most of the water sources come from ground water. Ground water in the Bandung State Polytechnic environment has acidic pH (<6), coliform> 2,400, and positive colitis. The process of water heating is less effective for treating ground water because it requires a relatively long time, large energy, and can not increase the pH of the water to meet drinking water standards as stated in Permenkes No. 492 / MENKES / PER / IV / 2010. To treat ground water in the Bandung State Polytechnic, portable drinking water treatment equipment has been made using the concept of dead-end flow filtration. The membrane used is a hollow-fiber membrane, a type of ultrafiltration membrane made from PVDF (Poly Vinylidene Fluoride), pore size of 0.1μm, membrane length of 15cm, membrane number of 148 pieces, and can be operated on normal human suction. The permeate produced is in accordance with PERMENKES No. 492 / MENKES / PER / IV / 2010 from physical, chemical and biological parameters. Lifetime membranes are observed through the amount of permeate produced from the beginning of the use of the membrane until the membrane is damaged. Lifetime of this portable drinking water treatment device is 38,879 L. Ground water treatment using this tool can increase pH by 12.78%, decrease conductivity by 39.31%, and reduce Total Dissolved Solid (TDS) 13.72%. From an economic standpoint, the use of this tool can save 50% costs compared to the purchase of 600 ml of bottled water.

The use of Stirred Tank Reactor (STR) in wastewater treatment requires a Clarifier in its operation so that Sequencing Batch Reactor (SBR) is an alternative solution. The clarifier is needed to recover some of the wasted microbes in the effluent stream. With SBR, the Clarifier function is replaced when the settle phase in the SBR operating cycle is executed. The four phases of SBR operation are carried out in stages and sequentially, namely, the fill, react, settle, and draw/decant phases. In this study, the performance of SBR and STR was compared in treating molasses-based wastewater. At an organic loading rate of 516 mg COD L -1 day -1 and 20 days HRT, these two types of reactors were capable to remove the COD content of wastewater with an efficiency of about 90%. At a hydraulic shock load of 10 days and the same organic loading rate, SBR showed its superiority. The organic compound removal efficiency of around 89% could still be maintained by SBR but the organic compound removal efficiency of only about 57% could be maintained by STR. The parameters of pH could be maintained by SBR in the pH range of 7.2 to 7.4, whereas the pH values in STR were in the pH range of 7.0 to 6.3.

Industrial WWTP sludge has not been used properly, especially biological process WWTP sludge can be used as an alternative fuel in the form of briquettes. The purpose of this study was to determine potential utilization of biological process WWTP sludge as briquettes, and to determine the effect of adding variations charcoal to the quality of briquettes. The biological process WWTP sludge was obtained from the Trio Food, Cianjur. The dried sludge has a calorific value 2468 cal/g. The research methodology includes material drying, size reduction (250 μm), mixing, molding, and briquette drying. Briquettes are made with variations in the addition of 30%, 40%, 50%, 60%, 70% charcoal. The results of the study showed that the addition of charcoal resulted increase in the water content, fixed carbon, and calorific value of briquettes as well decrease in ash content, and volatile matter. The highest calorific value in the variation of the addition charcoal is 70% at 3819 cal/g, the value still does not meet SNI 1/6235/2000 (standard for wood charcoal briquettes). The biological process WWTP sludge has potential to be used as fuel in the form of briquettes with the addition of coconut shell charcoal and carbonized coal.

The increase in population in Indonesia is directly proportional to the increase in the use of vehicles which results in an increase in fuel demand. The amount of fossil fuels continues to decrease and cannot be renewed, so alternative energy is needed, one of which is bioethanol. This study aims to make bioethanol from banana weevil waste, to determine the effect of fermentation time on the concentration of banana weevil bioethanol and to determine the concentration of bioethanol after going through the purification stage. The production of banana weevil bioethanol begins with the process of cutting the banana weevil which is then mashed with the help of water and then squeezed and starch is obtained and then hydrolyzed with the addition of glucoamylase and alpha-amylase enzymes for further anaerobic fermentation with the help of Saccharomyces cerevisiae with a concentration of 25%. In this study, variations of fermentation time were carried out for 5, 7, 9, and 10 days. The best fermentation time was obtained from 9 days of fermentation, where the conversion of glucose to bioethanol was 51%. The results of the analysis using a refractometer showed that the concentration of bioethanol obtained was 16.20% (v) which was obtained from fermentation for 9 days and purification using a rotary evaporator at a pressure of 360 mbar and a temperature of 500C.