Effect of anaerobic reactor process configuration on useful energy production

The effect of reactor process configuration on anaerobic production of useful energy (hydrogen and methane) from a complex substrate was investigated for the following reactor systems: suspended growth, two-phase mixed, two-stage mixed, upflow anaerobic sludge blanket (UASB) reactor, and two-phase UASB. The mixed two-phase and two-stage configurations yielded the highest specific energy productions of 13.3 and 13.4 kJ/g COD fed, respectively. Reactor process configuration influenced microbial pathways in acidogenic reactors in that butyrate was the predominant volatile acid in phased configurations, whereas acetate was predominant in the staged configuration. The UASB reactor achieved the highest average daily energy production per reactor volume of 101 kJ/L reactor-d. All reactor configurations achieved high COD removals on the order of 99%. However, hydrogen represented only 3% of the total energy produced by the two-phase mixed and two-phase UASB configurations. Theoretical analysis revealed that the maximum specific energy production by the two-phase suspended-growth configuration is only 9% higher than that for a single-stage mixed reactor. Consequently, the production of hydrogen from complex substrates in these process configurations does not seem to be justifiable solely from an energy point of view. Instead, it is suggested that phased anaerobic systems should be considered primarily for improved process stability whereas resultant hydrogen production is of secondary benefit.     

两级UASB+A/O处理玉米制糖废水工程实例

介绍了采用两级UASB+A/O工艺处理玉米制糖废水的工程实例,实际运行结果表明,系统运行稳定,处理出水COD≤91 mg·L-1,ρ(NH3-N)≤10mg·L-1,出水水质达到污水综合排放标准GB 8978-1996一级标准.     

厌氧-好氧工艺处理啤酒生产废水

根据啤酒废水属中高浓度有机废水,具有无毒有害的水质特点,将一套高效率的处理工艺(厌氧-好氧)设计应用于净化处理中.该工艺主要由厌氧的UASB反应器和好氧的SBR反应池构成,具有COD、SS的去除率高,设备运行稳定,工作效率高,且各个构筑物之间基本可实现重力自流,能够节约能耗的特点.并以兰州某啤酒厂为例,进水水质:COD 1 500～3 000 mg·L~(-1)、BOD_5800～1 600 mg·L~(-1)、p(SS)≤250～1 200 mg·L~(-1)、pH5～10,出水水质可达综合排放国家一级标准要求,各项指标的去除率分别为:COD97.7%、BOD_5 98%、SS 96%.     

Anaerobic biodegradability and treatment of grey water in upflow anaerobic sludge blanket (UASB) reactor

Feasibility of grey water treatment in an upflow anaerobic sludge blanket (UASB) reactor operated at different hydraulic retention time (HRT) of 16, 10 and 6h and controlled temperature of 30 degrees C was investigated. Moreover, the maximum anaerobic biodegradability without inoculum addition and maximum removal of chemical oxygen demand (COD) fractions in grey water were determined in batch experiments. High values of maximum anaerobic biodegradability (76%) and maximum COD removal in the UASB reactor (84%) were achieved. The results showed that the colloidal COD had the highest maximum anaerobic biodegradability (86%) and the suspended and dissolved COD had similar maximum anaerobic biodegradability of 70%. Furthermore, the results of the UASB reactor demonstrated that a total COD removal of 52-64% was obtained at HRT between 6 and 16 h. The UASB reactor removed 22-30% and 15-21% of total nitrogen and total phosphorous in the grey water, respectively, mainly due to the removal of particulate nutrients. The characteristics of the sludge in the UASB reactor confirmed that the reactor had a stable performance. The minimum sludge residence time and the maximum specific methanogenic activity of the sludge ranged between 27 and 93 days and 0.18 and 0.28 kg COD/(kg VS d).     

UASB工艺处理聚酯多元醇废水的研究

采用高负荷UASB工艺处理聚酯多元醇废水,分析了UASB有机负荷对CODCr去除率影响及其进水、出水pH的变化。研究表明,在中温(37±2℃)环境下,UASB有机负荷7 kg/(m3.d)时,CODCr去除率在85%以上,运行稳定。     

Internal Purification of Thermomechanical Pulp Clear Filtrate with a Combined Biological and Membrane Filtration Method: A Preliminary Study

Abstract

In this study a combined anaerobic biological-nanofiltration method was studied as a means of internal purification of a thermomechanical pulp (TMP) plant effluent. A TMP plant clear filtrate was first subjected to a thermophilic anaerobic treatment at 55 or 70°C in an up flow anaerobic sludge blanket reactor and then nanofiltered in a flat-sheet laboratory-scale module. The anaerobic treatment removed 55% of the chemical oxygen demand at 70°C and 65% at 55°C. Sugars were removed both at 55 and 70°C while the low molar mass ligneous material was removed only at 55°C. By nanofiltration the remaining low molar mass ligneous material was removed by about 98–99% and the high molar mass ligneous material by 96–99%. Sugar was removed by 88–98% and chemical oxygen demand by 78–81%. It was also shown that most of the pulp-brightness-decreasing substances had been removed. The permeate flux depended on the sample but was at its best [about 38 L/(m²-h) at 8 bar] for the first hour of filtration for the sample anaerobically treated at 55°C. The samples did not cause permanent fouling of the membrane. In this study it was shown that the combined anaerobic biological-nanofiltration method is a competitive internal purification method for TMP plant clear filtrate resulting in a very clean water, which could be reused in the water circulartion system of the plant or in the paper machine white-water system. However, further studies for optimization of the process are needed.     

挤占来进料加工市场提高国产树脂占有率

分析了来进料加工市场的特点 ,对国产树脂进入来进料加工市场所面临的问题作了一定深度的探讨 ,并提出了一些建议     

高负荷厌氧氨氧化的稳定性试验研究

为探讨高负荷条件下复合式UASB反应器中厌氧氨氧化反应的脱氮性能和稳定性,在已经成功启动并稳定运行的厌氧氨氧化反应器中,通过提高进水总氮浓度和缩短水力停留时间两种方式提高总氮负荷,考察脱氮效果。结果表明,通过逐步提高进水总氮浓度和缩短HRT可以提高厌氧氨氧化反应的总氮负荷,并获得理想的脱氮效果和运行稳定性,但过高的亚硝态氮浓度会对反应产生一定的抑制作用。     

规模化猪场粪污处理实例

猪场废水是高浓度有机废水，采用以UASB反应器为主要处理单元的生物处理工艺处理；工程实践证明，该工艺不仅投资省，运行费用低，而且产生可供利用的沼气，实现了猪场废水处理的资源化。     

预处理/UASB/MBR工艺处理萘系染料中间体废水

某染料中间体生产企业排放的废水污染物浓度高、盐度高、色度高、毒性大,废水量为240 m3/d,采用预处理/UASB/MBR工艺对其进行处理.调试结果表明:在进水硫酸盐≤7 500mg/L、COD≤3 500 mg/L的条件下,出水水质可达到<山东省海河流域水污染物综合排放标准>(DB 37/675-2007)的二级标准.