内循环三相流化床反应器处理味精废水的研究

研究以陶粒粒子为载体,采用快速排泥挂膜法,在内循环三相流化床反应器运行过程中逐渐加大进水量和进水浓度,使微生物适应高氨氮废水环境;研究了水力停留时间、NH4＋-N浓度负荷冲击对NH4＋-N去除率的影响.结果表明：内循环三相流化床可用于处理高NH4＋-N废水;底物浓度越高水力停留时间越长;内循环三相流化床具有较好的抗负荷冲击能力,有利于解决实际废水水质不稳定难以达标排放的困难.     

水力停留时间对改良型AAO-MBR工艺处理夏季农村生活污水的影响

水力停留时间(HRT)是影响AAO工艺脱氮除磷效率的重要因素.采用改良型AAO-MBR工艺处理某农村生活污水,考察了夏季时HRT对处理装置出水效果的影响.试验结果表明,该工艺对低浓度农村生活污水中CODCr、氨氮的去除效果较稳定,平均去除率分别为69.50％、98.90％.TN去除率为26.50％～56.60％,随厌氧...     

Effects of hydraulic and solids retention times on productivity and settleability of microbial (microalgal-bacterial) biomass grown on primary treated wastewater as a biofuel feedstock

High biomass productivity and efficient harvesting are currently recognized challenges in microbial biofuel applications. To produce naturally settleable biomass, combined growth of native microalgae and bacteria was facilitated in laboratory sequencing batch reactors (SBRs) using primary treated wastewater from the Christchurch Wastewater Treatment Plant (CWTP) in New Zealand. SBRs were operated under a simulated, local, summer climate (i.e., 925 μmol/m²/s of photosynthetically active radiation for 14.7 h per day at 21 °C mean water temperature) using 1.4- to 8-day hydraulic retention times (HRTs) to optimize growth. Solids retention times (SRTs) were varied from 4 to 40 days by discharging different ratios of supernatant and completely mixed culture. Biomass productivity up to 31 g/m²/day of solids was obtained, and it generally increased as retention times decreased. Biomass settleability was typically 70-95%, and the microbes aggregated into compact flocs as cultures aged up to four months. Due to a low lipid content of 10.5%, anaerobic digestion appeared to be the most appropriate biofuel conversion process with potential to generate 19,200 m³/ha/yr of methane based on settleable mixture productivity.     

Photolytic treatment of organic constituents and bacterial pathogens in secondary effluent of synthetic slaughterhouse wastewater

The reduction and degradation of total organic carbon (TOC) and bacteria from a secondary effluent of synthetic slaughterhouse wastewater using vacuum-ultraviolet (VUV) and ultraviolet-C (UV-C) processes and their combination (UV-C/VUV and VUV/UV-C) were investigated. The TOC removal rates under continuous mode operation ranged from 5.5 to 6.2%. In addition, the treatment with the UV-C/H₂O₂ and VUV/H₂O₂ processes under continuous mode operation doubled the TOC removal rates 10.8 and 12.2%, respectively. The optimum molar ratio of H₂O₂/TOC was found to be 2.5 and 1.5 for the UV-C and VUV processes, respectively. It was observed that all photochemical processes were able to totally inactivate different strains of bacteria with concentrations up to 10⁵ CFU/mL within 27.6 s. Finally, a kinetic model was developed to simulate the TOC degradation from a secondary effluent of synthetic slaughterhouse wastewater.     

注浆法在治理自燃矸石山工程中的应用

通过分析矸石自燃原理,提出采用注浆法对自燃矸石山进行治理,并结合某煤矿工程中矸石山治理实例,依据相关检测标准,证明了注浆法是治理自燃矸石山的一种有效方法。     

Dosing free nitrous acid for sulfide control in sewers: Results of field trials in Australia

Intermittent dosing of free nitrous acid (FNA), with or without the simultaneous dosing of hydrogen peroxide, is a new strategy developed recently for the control of sulfide production in sewers. Six-month field trials have been carried out in a rising main sewer in Australia (150 mm in diameter and 1080 m in length) to evaluate the performance of the strategy that was previously demonstrated in laboratory studies. In each trial, FNA was dosed at a pumping station for a period of 8 or 24 h, some with simultaneous hydrogen peroxide dosing. The sulfide control effectiveness was monitored by measuring, on-line, the dissolved sulfide concentration at a downstream location of the pipeline (828 m from the pumping station) and the gaseous H₂S concentration at the discharge manhole. Effective sulfide control was achieved in all nine consecutive trials, with sulfide production reduced by more than 80% in 10 days following each dose. Later trials achieved better control efficiency than the first few trials possibly due to the disrupting effects of FNA on sewer biofilms. This suggests that an initial strong dose (more chemical consumption) followed by maintenance dosing (less chemical consumption) could be a very cost-effective way to achieve consistent control efficiency. It was also found that heavy rainfall slowed the recovery of sulfide production after dosing, likely due to the dilution effects and reduced retention time. Overall, intermittent dose of FNA or FNA in combination with H₂O₂ was successfully demonstrated to be a cost-effective method for sulfide control in rising main sewers.     

Continuous fermentative hydrogen production from cheese whey – new insights into process stability

Continuous dark fermentation experiments for hydrogen production from synthetic cheese whey were conducted at different HRTs and OLRs. The study mainly aimed at developing a novel criterion to quantitatively assess stability and relating it to the evolution of microbial pathways and associated metabolic products.For HRTs = 6–8 h and OLRs = 65–97.5 g TOC/(L·d), the best hydrogen generation performance was attained, yielding 42–50 L H₂/kg TOC. Instead of using a stability index for the entire test length, accounting for the fluctuations of hydrogen production over 1-HRT periods (dynamic stability index) provided a more accurate assessment of process stability showing a clear correlation with the hydrogen yield. The analysis of the metabolic reactions provided evidence of a competition among acidogenic, hydrogen-consuming and hydrogen-neutral microbial species. This explained the lower process performance in comparison to the theoretical yield expected, pointing out at the need for further investigation on suitable strategies to effectively inhibit undesired metabolic pathways.     

MBBR法处理城市污水去除污染物的特性研究

通过对小试规模的移动床生物膜反应器(MBBR)处理南方热带亚热带地区城市生活污水的试验研究,探讨了水力停留时间、pH、填料填充率、冲击负荷对反应器处理效果的影响.试验结果表明,在NRT为6 h,进水COD为300mg·L-1,氨氮质量浓度为15 mg·L-1,填料体积填充率为30%,pH为7左右时,移动床生物膜反应器对COD、氨氮、TN的去除率分别为83.4%、80.1%、49.7%.     

HRT对悬挂链曝气式接触氧化处理污染河水的影响

考察了不同水力停留时间(HRT)下,厌氧-缺氧-悬挂链曝气式接触氧化对重,轻度污染河水的净化效果.结果表明,HRT为2、4、8,12h时,在重、轻度污水水质COD为58.67～85.33mg·L-1、26.67～42.67mg·L-1;NH4+-N为5.20～11.30 mg·L-1、2.79～3.47 mg·L-1,TN为8.10～14.18 mg·L-1,3.15～3.38mg·L-1;TP为0.62～O.82 mg·L-1,0.135～0.39mg·L-1两种典型进水水质情况下,COD、NH+-N和TN的平均去除率都随HRT的增加而升高,但在HRT为8 h后,平均去除率的增幅都变小.TP在重、轻度污水时随HRT变化去除率差异不大.考虑节能与效率,该工艺适宜的HRT为8 h,此时重、轻度污染河水的主要污染指标平均去除率COD为61.87%、25.39%;NH4+-N为61.25%、51.04%;TN为37.66%、26.51%;TP为10.19%、8.77%.     

ABR-MAP-MBR组合工艺处理高浓度养殖废水研究

针对养殖废水高悬浮物、高有机物及高氨氮的特点,采用厌氧折流板反应器/磷酸铵镁沉淀/兼氧-好氧膜生物反应器（ABR-MAP-MBR）组合新工艺对其进行中试处理研究,考察生物反应器的启动运行条件;考察水力停留时间（HRT）、水温和溶解氧（DO）等运行参数对养殖场废水各阶段处理效果的影响;考察MAP沉淀法对ABR厌氧出水的NH₄-N去除效果。结果表明：采用阶梯负荷启动策略,60 d完成ABR反应器的启动,厌氧环节在HRT为24 h、水温25～35℃时COD去除率达73.5%;磷酸铵镁沉淀过程中选择氯化镁、磷酸三钠作为沉淀剂,控制Mg²⁺∶NH₄⁺∶PO₄^3-摩尔比为1.2∶1∶0.95,pH为8.5～9.0条件下处理ABR厌氧出水,COD、NH₄-N和PO₄^3--P去除率分别为28.2%、85.4%和89.7%;通过对A/O-MBR反应器HRT和DO的条件优化,该单元的COD、SS、NH₄-N和TN等指标的去除率分别为82.0%、95.2%、72.4%和67.7%（HRT=16 h,O区DO≥3.0 mg·L^-1）。经过组合工艺的综合处理,系统出水各项主要指标（SS、COD、TN和TP等）达到《畜禽养殖业污染物排放标准》（GB 18596-2001）一级排放标准,表明该新工艺在规模化养殖场废水处理中具有良好的应用前景。