流速对垃圾渗滤液EGSB发酵产氢的影响

以生活垃圾堆肥厂初期渗滤液为对象,以厌氧颗粒污泥为接种物,研究了液体上升流速(Vup)对EGSB反应器厌氧发酵制氢系统的影响。分析了进、出水中CODCr、p H值、挥发性脂肪酸(VFAs)的变化及产气量和成分。结果表明在中温(35±1)℃,p H值为5.0~5.5,水力停留时间为24 h的条件下,液体上升速度的变化对系统的产氢能力有所影响,在Vup为3.7 m/h时,系统的CODCr去除率、氢气产生速率分别为49.6%~51.6%、1 996~2 183m L/(L·d),两者值均高于其它阶段,液相末端发酵产物中乙醇和乙酸总量占VFAs总量的80%以上,发酵类型以乙醇型发酵为主。     

UASB工艺在啤酒废水处理中的应用

安徽某大型啤酒厂的工程实践证明，采用内循环UASB反应器＋好氧工艺处理啤酒废水是可行的。因设计了出水内循环并加装了斜板分离器，在实际调试与运行中UASB系统适应pH值和温度的范围较宽，运行稳定、处理效率高、能耗低，在春季时系统重新启动可很快得以恢复。     

升流式厌氧污泥床(UASB)反应器处理城市污水试验研究

升流式厌氧污泥床(Upflow Anaerobic Sludge Blanket,简称UASB)反应器是荷兰学者Lettinga等人在70年代初开发的,主要用于处理高有机负荷的工业废水。由于其结构紧凑、处理效率高、节能等优点,近年来,各国开始探索UASB在处理负荷较低的生活污水和城市综合废水上的应用。该文介绍了利用UASB处理城市生活污水试验的结果;试验现场设在上海奉贤,进水为污水泵站的高有机负荷的原水,CODCr的范围:200~2 000 mg/L,UASB内污泥浓度:4 100 mg/L。出水进入后续的高负荷生物滤池进行下一步处理。该UASB是整个处理流程6段中的一段。当水力停留时间为6 h时,CODCr平均去除率为37.0%;BOD5平均去除率为36.2%;SS平均去除率为38.9%。     

水溶性胶黏剂生产废水处理工程实例

针对水溶性胶黏剂生产废水有机物含量较高、水质波动大、难生物降解等特点,采用Fenton氧化+混凝沉淀+UASB+生物滤池的组合工艺对其进行处理。运行结果表明,系统运行稳定,出水COD≤500 mg/L,氨氮≤25 mg/L,SS≤400 mg/L,处理出水达到《污水综合排放标准》(GB 8978-1996)的三级标准,COD、氨氮、SS去除率分别为93.6%、56.9%、89.5%,工艺处理成本为6.8元/m^3。     

Pre-acidification in anaerobic sludge bed process treating brewery wastewater

The effect of pre-acidification on anaerobic granule bed processes treating brewery wastewater was the focus of a comparison study employing two configurations, (a) a single stage upflow anaerobic sludge bed (UASB) and (b) an upflow acidification reactor in series with a methanogenic UASB. The pre-acidification reactor achieved 20±4% SCOD removal and 0.08±0.003 L of methane produced per gram of SCOD removal at a hydraulic retention time (HRT) of 0.75–4 h. Butyric acid was not detected and short chain fatty acids (SCFAs) were mainly acetic and propionic acids. The acidification ratio was about 0.42±0.02 g SCFAs as COD/g of influent COD.

Both systems’ critical loading rate to achieve 80% COD removal was established at 34–39 kg COD/m³ of total sludge bed volume per day. SCOD removal efficiency of 90±3% was achieved by both systems at an organic loading rate of 25±1 kg COD/m³ of total sludge bed volume per day, indicating that the installation of an acidification reactor had no effect in terms of the maximum granular activity, biomass granulation and the settleability of granules. At an organic loading rate of 67 kg COD/m³ of total sludge bed volume per day at an HRT of 1 h, the series system outperformed the single UASB by a removal of 62 compared to 57%.     

上向流粗滤工艺实验与计算机模拟

尝试采用上向流粗滤,作为慢滤池的预处理。由于粗滤池的运行周期很长,故采用了计算机模拟的方式观察运行参数变化对粗滤池的影响。试验及模拟结果均表明：此上向流粗滤操作维护简单,运行稳定。     

两段厌氧工艺处理含硫酸盐、氨氮废水的研究

将两段UASB反应器用于处理含高浓度硫酸盐、氨氮的有机废水,结果表明CODCr的去除率>95%,总磷的去除率>55%。第1段反应器进水的CODCr、硫酸盐、氨氮分别在11000、2800、1000mg/L时,硫酸盐、CODCr去除率分别为>96%、>87%;厌氧生物处理过程中,废水中的游离NH3与产生的H2S、VFA、CO2相互作用,有利于厌氧生物处理的顺利进行。第2段反应器进水pH7.7～7.8,出水pH>8.0,CODCr去除率为65%～75%。扫描电镜照片显示,两段反应器中占优势的微生物种群不同。     

水解酸化-厌氧-好氧工艺处理抗生素废水

试验采用生化工艺处理高浓度抗生素废水。结果表明 ,水解酸化反应器最大COD容积负荷达到 1 6.84kg/(m3·d)。厌氧复合床处理水解酸化后的抗生素废水 ,当容积负荷为 6.0kg/(m3·d)时 ,反应器对SS、COD、BOD5 的去除率分别为 75.6%、91 .7%、96.1 % ;厌氧出水采用周期循环活性污泥系统进行处理 ,当容积负荷为 1 .6kg/(m3·d)时 ,反应器对SS、COD、BOD5 的去除率分别为 91 .6%、88.7%、95.4%。     

Characteristics of Cocurrent Two-Phase Downflow in Tubes

An experimental study was made in a cocurrent downflow for air-water system in tube on flow pattern, void fraction and pressure drop. In addition to wetted wall flow which is a distinguished feature in downflow, the same kinds of flow patterns as in up-flow were observed. They were represented on the flow map of downflow with the same variables as those of upflow. The flow maps showed that gas phase is relatively hard to exist in the form of bubble in the cocurrent downflow.

General correlations of the void fraction and the pressure drop in a cocurrent down-flow were obtained by applying the following equations which have been established in upflow, i.e. α/(1-α)(1-Kα)=β/(1-β) for void fraction and φl=(1.α)- ^z for pressure drop. The determined values of K and Z by using the experimental results in the present study and other experimental works in cocurrent downflow wereK=2.0–0.4/β for β≤0.2, K=-0.25+1.250 for β≥0.2 and Z=0.90.

Comparisons between the predicted values by the presented correlations and experimental data showed satisfactory agreement.