Effluent treatment of industrial wastewater using processed solid residue of olive mill products and commercial activated carbon

The carbonised solid residue of olive mill products, called J-carbon (0·6–0·7 mm), was compared with Sigma activated carbon (powder) and Chemviron activated carbon (0·6–0·7 mm) in treatment of the effluent of Flexsys' wastewater. The removal of NH₃, TOC as non-specific organics, and six specific leading organic pollutants from Flexsys' wastewater effluent were examined. All three different carbon sources have almost similar behaviour in removing the above pollutants; the removal efficiencies were as follows: Sigma carbon: benzothiazole, 1,2-dihydro-2,2,4-trimethylquinoline, N-dimorpholinyl ketone, methylsulphyl benzothiazole and methyl-2-benzothiazole sulphone 100%>TOC 94%>NH₃ 82%>tetrachloroethene 50%. Chemviron carbon: benzothiazole, 1,2-dihydro-2,2,4-trimethylquinoline, N-dimorpholinyl ketone, methylsulphyl benzothiazole and methyl-2-benzothiazole sulphone 100%>NH₃ 87%>TOC 40%>tetrachloroethene 31%. J-carbon: benzothiazole, methylsulphyl benzothiazole and methyl-2-benzothiazole sulphone 100%>NH₃ 78%>1,2-dihydro-2,2,4-trimethylquinoline 70%>tetrachloroethene 58%>N-dimorpholinyl ketone 50%>TOC 37%. © 1998 SCI     

粉末活性炭静态吸附水中硝基酚的试验研究

研究了常温(20℃)条件下粉末活性炭(PAC)对水中3-硝基酚、4-硝基酚、2,6-二硝基酚和2,4-二硝基酚4种硝基酚的静态吸附规律;并对照研究了未驯化的灭活活性污泥存在时,PAC对硝基酚的吸附性能。结果表明:PAC对4种硝基酚的吸附能力远大于灭活活性污泥;当硝基酚与PAC的质量比值在0.2~1.0时,PAC对4种硝基酚的吸附在60 min内可达到平衡,且均符合Langmiur吸附模型;用Langmiur吸附模型对试验数据进行拟合,得出了PAC对4种硝基酚的饱和吸附容量和吸附系数。     

Modeling and simulation of the sequencing batch reactor at a full‐scale municipal wastewater treatment plant

In this work, we attempted to modify the Activated Sludge Model No.3 and to simulate the performance of a full‐scale sequencing batch reactor (SBR) plant for municipal wastewater treatment. The long‐term dynamic data from the continuous operation of this SBR plant were simulated. The influent wastewater composition was characterized using batch measurements. After incorporating all the relevant processes, the sensitivity of the stoichiometric and kinetic coefficients for the model was thoroughly analyzed prior to the model calibration. The modified model was calibrated and validated with the data from both batch‐ and full‐scale experiments. Model predictions were compared with routine data in terms of chemical oxygen demand, NH₄⁺‐N and mixed liquid volatile suspended solids in the SBR, combined with batch experimental data under different conditions. The model predictions match the experimental results well, demonstrating that the model is appropriate to simulate the performance of a full‐scale wastewater treatment plant even operated under perturbation conditions. © 2009 American Institute of Chemical Engineers AIChE J, 2009     

Treatment of wastewater from acrylonitrile‐butadiene‐styrene (ABS) resin manufacturing by biological activated carbon (BAC)

Background: The wastewater originating from the production of acrylonitrile‐butadiene‐styrene (ABS) resin is a toxic and refractory industrial wastewater. The purpose of this work is to investigate the characteristics of adsorption and biodegradation of biological activated carbon (BAC) for ABS resin wastewater. Results: More than 80% of chemical oxygen demand (COD), total organic carbon (TOC) and organic nitrogen (Org‐N) was removed after the 100th run in BAC with the help of bioregeneration, and the treatment efficiency of BAC was higher than that of adsorption and biodegradation alone. The initial Org‐N was mainly transformed into NH₄⁺‐N, and the transform efficiency reached 65% after the 100th run. After bioregeneration, the COD and TOC removal efficiencies of BAC reactor reached 88.97% and 86.26%, respectively. The BAC had different bioregeneration efficiencies of 94.41, 64.82, 61.05 and 40.04% for 3, 3‐imminodipropiononitrile, 3, 3‐oxydipropiononitrile, α, α‐dimethyl‐benzylalcohol and acetophenone, respectively, which mainly resulted from the different polarity of the compounds. Conclusion: BAC could protect microorganisms from shock loadings of toxic, refractory and complicated ABS resin wastewater. The mechanism of the organic pollutants removal by BAC consisted of three phases including adsorption, bioregeneration and stability. © 2012 Society of Chemical Industry     

Removal of perfluorinated compounds by membrane bioreactor with powdered activated carbon (PAC): Adsorption onto sludge and PAC

The comparative study was conducted to investigate the performance and removal efficiencies of PFOS and PFOA in MBR and PAC-MBR. Solid phase extraction (SPE) followed by HPLC coupled with tandem MS (HPLC/MS/MS) was applied to quantitatively identify PFOS and PFOA in aqueous and sludge samples. Removal efficiencies of these two compounds were less than 7% in MBR, which suggest that MBR could not effectively remove PFCs due to their persistent in the activated sludge process. In contrast, removal efficiencies of 77.4% for PFOS and 67.7% for PFOA were observed in PAC-MBR with PAC dosage of 30 mg/L, indicating that adsorption of PFCs onto PAC plays an important role in their removal. Moreover, with the increase of PAC dosage from 30 mg/L to 100 mg/L in PAC-MBR, removal efficiency for PFOS or PFOA both increased to more than 90%. Mass balance of PFOS and PFOA was established to explore their removal mechanisms in MBR and PAC-MBR. Results show that PAC-MBR can effectively remove these two compounds in the wastewater by PAC adsorption, which was identified as the major removal mechanism. In MBR, adsorption onto activated sludge was the only mechanism for removal of PFCs.     

生物技术在屠宰废水处理中的应用研究进展

屠宰废水富含油,碳氮比、碳磷比高,且水质变化较大,是一类典型的有机废水。系统地介绍了目前国内外屠宰废水的主要生物处理技术及其研究现状,结果表明:单一的生物处理技术降解此类废水,很难达到预期效果,SBR组合工艺将是处理屠宰废水经济有效的工艺。     

工业废水活性污泥法设计参数和计算公式的探讨

工业废水种类繁多,并且大部分工业废水的水质特性与城镇污水之间存在较大差别,适用于城镇污水处理设计的参数和计算公式不一定适用于工业废水。对我国现行废水处理设计规范中活性污泥法的主要设计参数进行了汇总,分析了这些规范中存在的一些不足之处,包括以BOD5表征有机物含量的合理性,以泥龄法计算生化池容积和剩余污泥量的局限性,以及A/O法缺氧池(区)容积规定存在的误区等,并对工业废水处理的设计提出了建议。     

A calibration methodology and model‐based systems analysis for SBRs removing nutrients under limited aeration conditions

A methodology is proposed for the model calibration of nutrient‐removing laboratory‐scale SBRs under limited aeration. Based on in‐process measurements and influent wastewater characterization, the ASM2d model was modified by adding an organic nitrogen module incorporating a hydrolysis mechanism. After calibration, the simulation results showed that enhanced biological nutrient removal occurred during the fill period and under reduced aeration achieving so‐called ‘simultaneous nutrient removal’. A model‐based systems analysis was performed in terms of the contributions of different processes to overall oxygen, nitrogen and phosphate utilization. In each phase, simultaneously occurring biological reactions were compared using the calibrated model. According to the calibrated model, 61% of all denitrified nitrate is denitrified during the mixing/filling phase. On the other hand, 17% of all denitrified nitrate is consumed by simultaneous nitrification–denitrification during the first aerobic period. The aerobic and anoxic P‐removals were quantified as 73% and 12%, respectively. Copyright © 2006 Society of Chemical Industry     

Addition of activated carbon to batch activated sludge reactors in the treatment of landfill leachate and domestic wastewater

Leachate from a municipal landfill was combined with domestic wastewater and was treated in batch activated sludge systems. The effectiveness and applicability of the addition of Powdered Activated Carbon (PAC) to activated sludge reactors was investigated. Isotherm tests were carried out with PAC in order to estimate the extent of adsorption of organic matter onto PAC. Then, in activated sludge reactors COD (Chemical Oxygen Demand) removal and nitrification were studied both in the absence and presence of PAC for comparison purposes. In both cases, Oxygen Uptake Rates (OUR) were measured with respect to time in order to investigate substrate removal and change in microbial activity. Addition of PAC to activated sludge increased COD removal by removing mainly the non‐biodegradable fraction in leachate. The COD decreases in batch reactors were best expressed by a first‐order kinetic model that incorporated this non‐biodegradable leachate fraction. With added PAC, nitrification was also enhanced. But in all of the batch runs a significant accumulation of NO₂ ‐N took place, indicating that the second step of nitrification was still inhibited. © 2001 Society of Chemical Industry     

渐增NaCl对印染废水处理系统活性污泥微生物的影响

为了阐明在印染废水循环过程中积累的无机盐对生物处理系统的影响,本研究通过NaCl渐增实验研究了印染废水处理系统中活性污泥微生物的耐盐特性,并采用Biolog技术研究了Na Cl浓度逐渐升高过程中活性污泥微生物的代谢特征和多样性变化。结果表明,进水NaCl浓度逐渐升高会减少微生物的多样性,抑制微生物的活性,削弱其对酸类和酯类的利用能力。     

Periwinkle shell: Based granular activated carbon for treatment of chemical oxygen demand (COD) in industrial wastewater

The present investigation was undertaken to compare the adsorption efficiency of a low cost adsorbent, periwinkle shell—based granular activated carbon (PSC) with the adsorption efficiency of the commercial activated carbon (CAC) and a ratio 1:1 mixture of PSC and CAC (PSC/CAC) with respect to uptake of the organic components responsible for the chemical oxygen demand (COD) of industrial wastewater. The influence of treatment time, adsorbent dose, pH of the media, agitation speed and adsorbent particle size on the rate of percent COD removal is evaluated. PSC has shown quite effective adsorbent capacity for COD removal with 77.5% efficiency. Though its capacity is slightly lower than that of CAC with 79% efficiency, however the low material cost makes it an attractive option for the treatment of COD. The equilibrium adsorption study can be described by the Linear, Langmuir and Freundlich models. The mechanisms of the rate of adsorption of COD were analysed using the Elovich equation and a pseudo‐second‐order model. The models provided a very high degree of correlation of the experimental adsorption rate data suggesting either model could be used in design applications.     

A kinetic evaluation of the anaerobic digestion of two‐phase olive mill effluent in batch reactors

A comparative kinetic study was carried out on the anaerobic digestion of two‐phase olive mill effluent (TPOME) using three 1‐dm³ volume stirred tank reactors, one with freely suspended biomass (control), and the other two with biomass supported on polyvinyl chloride (PVC) and bentonite (aluminium silicate), respectively. The reactors were batch fed at mesophilic temperature (35 °C) using volumes of TPOME of between 50 and 600 cm³, corresponding to chemical oxygen demand (COD) loadings in the range of 1.02–14.22 g, respectively. The process followed first‐order kinetics and the specific rate constants, K₀, were calculated. The K₀ values decreased considerably from 2.59 to 0.14 d^?1, from 1.93 to 0.23 d^?1 and from 1.52 to 0.17 d^?1 for the reactors with suspended biomass (control) and biomass immobilized on PVC and bentonite, respectively, when the COD loadings increased from 1.02 to 14.22 g; this showed an inhibition phenomenon in the three reactors studied. The values of the critical inhibitory substrate concentration (S*), theoretical kinetic constant without inhibition (K_A) and the inhibition coefficient or inhibitory parameter for each reactor (n) were determined using the Levenspiel model. Copyright © 2004 Society of Chemical Industry     

Comparison of the filtration characteristics between biological powdered activated carbon sludge and activated sludge in submerged membrane bioreactors

The filtration performances of submerged membrane bioreactors (SMBR) with and without the addition of powdered activated carbon (PAC) were investigated respectively under the same feed and operation conditions. A series of experiments were conducted to analyze near-critical flux, effect of air-scouring rate and time of stable filtration operation of both systems. The experimental results demonstrated that pronounced flux enhancement was achieved by adding 1.2 g/L PAC. The near-critical flux for the biological powdered activated carbon (BPAC) system was about 32% higher than that for the activated sludge (AS) system. Increasing the air-scouring rate led to a more significant flux improvement for the BPAC system compared to the AS system. Long-term operation indicated that, at constant flux, the TMP increasing rate of the BPAC system could be lagged and thus cause the extension of operating intervals about 1.8 times compared to the AS system. Quantitative calculations showed the total hydraulic resistance of the BPAC system was about 44% lower than that of the AS system, and this decrease was mainly caused by the reduction in cake resistance. Analyses were then made from various aspects such as floc size distribution and apparent viscosity of the mixed liquor to elucidate the major factors giving rise to different filtration characteristics.