Industrial wastewater treatment using Sequencing Batch Reactor (SBR) can improve effluent quality at lower cost than that obtained by other biological treatment methods. Further optimization is still required to enhance effluent quality until it meets standard quality and to reduce the operating cost of treatment of high strength organic wastewater. The purpose of this research was to determine the effect of pretreatment (pH adjustment and prechlorination) and aeration time on effluent quality and COD removal rate in tapioca wastewater treatment using SBR. Pretreatment was done by (1) adjustment of tapioca wastewater pH to control (4.92), 7, and 8, and (2) tapioca wastewater prechlorination at pH 8 during hour using calcium hypochlorite in variation dosages 0, 2, 4, 6 mg/L Cl2, SBR operation was conducted according to following steps: (1) Filling of pre-treated wastewater into a bioreactor during 1 hour, and (2) aeration of the mixture of tapioca wastewater and activated sludge during 8 hours. Effluent sample was collected at every 2-hours aeration for COD analysis. COD removal rate mathematical formula was got by first deriving the best fit function between aeration time and COD. Optimum aeration time resulting in no COD removal rate. The value of COD effluent and its removal rate in optimum aeration time was used to determine the recommended of operation condition of pretreatment. Research result shows that chosen pH operation condition is pH 8. Prechorination can make effluent quality which meets standard quality and highest COD removal rate. The chosen Cl2 dosage is 6 mg/L.

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Vinase anaerobic treatment is a one alternative process to treating vinasse. Microaeration is a one of process modification in anaerobic vinasse digestion that can improve the acidogenic performance. In this paper presents the influence microaeration in anaerobic vinasse treatment in kinetics aspect. The kinetics aspect was develop to approach and quantifying the effect of microaeration in anaerobic vinasse treatment systematically. Extract of cow dung was used as inoculums and vinasse 100 ppm as a substrate. Laboratory experiments using 4L vertical reactor (UASB) was conducted in 28 days and performed in batch recirculation mode. During the experiment, dosing air in different concentrations was injected in the slurry phase into different anaerobic digesters once a day. The variation of air concentrations are 0 L air/L feed; 0.5 L air/L feed; and 100 L air/L feed. As the result, the addition of 0.5 Lair/L feed could increase biodegradability (k=-5.7239) and accelerate acidogenesis phase (μm1=2.03/day) that can be proven by the percentage of VS removal reaching up to 77% and cuts the lag phase (λ=1.028 days) and HRT making it shorter.

Modifikasi vermiculite dilakukan untuk meningkatkan afinitasnya sebagai media imobilisasi bakteri anaerob. Penelitian ini bertujuan untuk mempelajari pengaruh vermiculite termodifikasi Cu 2+ dalam proses produksi biogas terhadap parameter kinetika. Penelitian ini dilakukan menggunakan tiga digester, yaitu digester tanpa penambahan vermiculite termodifikasi Cu 2+ , digester dengan penambahan vermiculite termodifikasi Cu 2+ 0,01 mg/L dan digester dengan penambahan vermiculite termodifikasi Cu 2+ 0,5 mg/L. Hasil yang diperoleh adalah semua digester dengan penambahan vermiculite termodifikasi Cu 2+ sebanyak 40 g memberikan peningkatan pada nilai laju pertumbuhan spesifik bakteri asidogen dibandingkan dengan digester tanpa penambahan vermiculite termodifikasi yaitu sebesar 48 %. Penurunan laju pentumbuhan spesifik bakteri metanogen hanya terjadi pada digester dengan penambahan vermiculite termodifikasi Cu 2+ 0,5 mg/L hingga 88,87 %.