Acclimatization studies for degradation of Acid Red 3BN dye and its treatment in moving bed biofilm reactor

In this study, acclimatization of microorganisms for the degradation of Acid Red 3BN dye bearing water (AR3BNDW) using activated sludge was performed in a cylindrical aerobic reactor. The initial value of chemical oxygen demand (COD), dye, and mixed liquor suspended solids (MLSS) of activated sludge were evaluated as 870.5, 80.6 and 1200 mg/L The experiments were performed at ambient temperature (25–35 °C) and the stabilization was achieved at 15 d. Maximum reduction of chemical oxygen demand (COD) and color were observed to be 94.2%, and 91% after 15 d of acclimatization. After completion of acclimatization process, degradation of dye was studied in moving bed biofilm reactor (MBBR). In the process, 38, 50, 68 and 76% color reduction were achieved with polymer carrier fill ratio (FR) of 40, 50, 60 and 70%, respectively in 24 h. For effluent flow rate of 180, 240, 300 and 360 mL/h, respectively, the dye reductions of 76, 60, 48 and 36% and COD reductions of 72, 58, 46 and 34% were achieved in 24 h

Testing of a novel IFAS-MBR process with Co-precipitation

IFAS-MBR with co-precipitation, not yet commonly used in practice, will result in a very compact process for nutrient removal. The process, based on a combined pre- and post-denitrification IFAS process with membrane separation (IFAS-MBR), was tested in two parallel small-scale plants. Train A was operated with co-precipitation in order to achieve high removal of total P (TP). Train B, without co-precipitation, served as a control. Due to the coagulant (Al) addition, the concern was precipitation on the biofilm carriers in the aerobic reactor in Train A. A small internal air-lift pump proved to be very efficient in controlling biofilm thickness and removing excess biofilm mass as needed. A coagulant dose equivalent to an Al/TP molar ratio of 1.9 was necessary to achieve 99% TP removal and 0.10 mg TP/l in the effluent of Train A. Very good removal of total N was achieved in both trains. Train A had a biofilm nitrification rate of 0.65 g NH4-N/m2d at 12–13 °C and 5.2–5.6 mg O2/l. The tests demonstrated that an IFAS-MBR process with co-precipitation and an aerobic suspended biomass SRT of 5–10 days is feasible, and that all the performance goals set up for the full-scale plant were achieved.

Application of Biofilm Carrier in Aerobic Reactors as a Method to Improve Quality of Wastewater Treatment

The research revealed in the paper considers the improvement of secondary treatment of wastewater in the aerobic reactor to provide removal of organics and nutrients. There were five types of polymer biofilm carriers taken into account initially; however, two of them were decided not to apply due to technological reasons. The main part of the research was divided into three substages to investigate each type of biofilm carrier. According to the literature review, the optimal efficiency may be reached if the carrier filling ratio is 10 to 30% of reactor volume. On this basis, there were three benches launched at each sub-stage with a corresponding filling ratio of 10, 20, and 30%. The fourth reactor at each sub-stage had no floating carrier to control the experiment. The research of all three types of carriers showed the effect of BOD removal in the range of 95–96% for benches equipped with a floating carrier, which can be considered similar to the control bench with the efficiency of 92%. In the case of ammonia nitrogen, the removal control bench showed only 55% of efficiency, while floating carriers helped to increase the efficiency up to 70–86%. Despite obtaining relatively positive results, the research has to be continued to achieve regulation requirements in treatment quality.

Hydrogenotrophic denitrification for treating nitrate contaminated without/with reactive black 5 dye

NO3-N and dye colors discharged from textile wastewater pose environmental problems in Thailand. This study aimed to observe the nitrogen removal rate (NRR) with and without RB-5 color contamination via hydrogenotrophic denitrification (HD) processing, which uses H2 gas as electron donor to reduce NO3-N and NO2-N; comparing with bioreactors treatment to evaluate systems that can simultaneously remove NO3-N and dye color. Five reactors under different operation and gas supply conditions were set-up under HRT of 24 h, including an aerobic reactor using air, two anaerobic reactors using argon and H2, and a combined process using intermittent air/argon and air/H2. NRR without dye varied between 45 and 90% for H2 and air/H2 by HD processing, while it was completely removed when adding color. H2 and air/H2 reactors experienced partial decolorization of approximately 20–30%, whereas the other three reactors remained unchanged. Effluent of NO3-N were close to wastewater standards, but the color was still easy to detect, which indicated that the treatment time needs to be sufficient. In conclusion, HD and intermittent air/H2 processing can completely remove NO3-N and NO2-N when contaminated with RB-5 color. Furthermore, RB-5 did not affect the NRR, whereas some particles of dye color can also reduce in these processes.

Treatment of Olive Mill Effluent Wastewater Using Some Advanced Processes and Reuse of the Treated Wastewater

In this study it was aimed to treat the Olive mill effluent wastewater using different sequential treatment processes namely anaerobic and aerobic biological processes, sonication and photo degradation with Nano SiO2 under sun ligth power. The maximum total COD yields were 60 % and 66 % in the anaerobic and aerobic reactor, respectively, while the total COD yield in the sequential biologic reactor was 86 %.The maximum COD yields in the sonicator was 53 % after 45 min retention time. No removal of COD was observed via photolysis and adsorption. The maximum photo catalytic removal of COD was 40 % at a nano SO2 concentration of 0,5 mg/l after 10-60 min. After RO the COD yield was approximately 100% while to yields of total phenol, TN, TP, dissolved COD and DSS were 96.6%, 99.3%, 99.98%, and 99.97%, respectively. The cost to treat 1 m3 of OMW was 1.033 €. The effluent of RO can be used as irrigation water.