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951.
为了生态厕所的推广使用、便于操作和节约能耗,多采用无加热的设施,即在自然条件下(对于小型生态厕所,接近中温条件)的好氧堆肥处理.了解中温好氧堆肥过程有机物的降解特性,对于生态厕所的推广使用和简化设计、操作等具有重要意义.采用密闭式好氧堆肥反应器,模拟中温(35℃)的堆肥温度,以新鲜锯末为空白载体,在含水率为60%以及连... 相似文献
952.
二氧化硫和氮氧化物是电厂产生的主要大气污染物,研究焦点越来越集中在在一个反应器内实现同时脱硫脱硝。实验以H2O溶液作为吸收液,在自制的鼓泡反应器内,对模拟烟气进行同时脱硫脱硝的实验研究,实验结果表明:H2O浓度、反应温度、NO浓度、SO2浓度、烟气流量对脱除率影响显著,pH、氧含量对脱硝率影响不大。在整个实验范围内脱硫效率总是保持在98.5%以上,脱硝效率最高达到67.4%。 相似文献
953.
954.
Improvement of fruit and vegetable waste anaerobic digestion performance and stability with co-substrates addition 总被引:1,自引:0,他引:1
The effect of fish waste (FW), abattoir wastewater (AW) and waste activated sludge (WAS) addition as co-substrates on the fruit and vegetable waste (FVW) anaerobic digestion performance was investigated under mesophilic conditions using four anaerobic sequencing batch reactors (ASBR) with the aim of finding the better co-substrate for the enhanced performance of co-digestion. The reactors were operated at an organic loading rate of 2.46–2.51 g volatile solids (VS) l−1 d−1, of which approximately 90% were from FVW, and a hydraulic retention time of 10 days. It was observed that AW and WAS additions with a ratio of 10% VS enhanced biogas yield by 51.5% and 43.8% and total volatile solids removal by 10% and 11.7%, respectively. However FW addition led to improvement of the process stability, as indicated by the low VFAs/Alkalinity ratio of 0.28, and permitted anaerobic digestion of FVW without chemical alkali addition. Despite a considerable decrease in the C/N ratio from 34.2 to 27.6, the addition of FW slightly improved the gas production yield (8.1%) compared to anaerobic digestion of FVW alone. A C/N ratio between 22 and 25 seemed to be better for anaerobic co-digestion of FVW with its co-substrates. The most significant factor for enhanced FVW digestion performance was the improved organic nitrogen content provided by the additional wastes. Consequently, the occurrence of an imbalance between the different groups of anaerobic bacteria which may take place in unstable anaerobic digestion of FVW could be prevented. 相似文献
955.
Treatment of domestic wastewater using an anaerobic baffled reactor followed by a duckweed pond for agricultural purposes 总被引:2,自引:0,他引:2
The treatment and reuse of domestic wastewater using an anaerobic baffled reactor (ABR) followed by a duckweed pond (DWP)
were the main theme of the present study. The ABR was fed continuously with domestic wastewater at four HRTs ranging from
8 to 24 h and corresponds to organic loading rates ranging from 0.67 to 2.1 kg COD/m3/day. The ABR effluent was fed to a DWP operating at 10 and 15 days. The performance of the ABR at the four HRTs gave satisfactory
results. Chemical oxygen demand (COD) removal was between 68 and 82%. Fecal coliform removal was between 1 to 2 logs. The
12- and 18-h hydraulic retention times (HRTs) gave close results, as indication of the possible selection of the 12-h HRT
as the optimum operation for the ABR based on economic advantage. The ABR compartmentalized structure gave results higher
than those produced by the one-stage digester and similar to those produced by the two-phase anaerobic digestion process.
Duckweed ponds as post-treatment operated at 10 days and 15 days gave the best results at 15-day HRT, where it was possible
to remove 73.4% of nitrogen and 65% of phosphorus and produce protein-rich dry duckweed of 105 kg/ha/day on average. The removal
of fecal coliform (FC) in duckweed ponds was 3–4 logs. The final treated domestic sewage characteristics proved its compliance
with the Egyptian standards for reuse in restricted irrigation. 相似文献
956.
序批式生物膜反应器不同填料挂膜及短程硝化特性研究 总被引:4,自引:0,他引:4
以实际生活污水为研究对象,采用序批式生物膜反应器(SBBR),填充不同种类的填料,针对其各自的挂膜特征和短程硝化的实现与稳定的特性进行了研究.结果表明,与立方体海绵填料相比,炭纤维填料的SBBR能够更快地实现挂膜启动,硝化效果稳定、高效(NH_4~+-N去除率高达99.3%);立方体海绵填料更易在常温下,实现NO_2~--N大量积累的短程硝化,但是相比而言,硝化效率不高.升高温度至30 ℃左右时,能够在30 d内实现炭纤维填料的短程硝化,通过过程控制可以实现短程硝化的稳定.荧光原位杂交技术(FISH)检测结果证实,SBBR中短程硝化的实现与稳定是因为菌群得到了优化,氨氧化细菌成为优势菌种. 相似文献
957.
研究以厌氧颗粒污泥接种的复合式厌氧折流板反应器(HABR)启动:在HABR中直接接种厌氧颗粒污泥,以退浆废水为试验进水,在系统水力停留时间为168 h,中温(32±1) ℃,进水pH值6.5~8,碱度适当偏高条件下,进入反应器废水COD浓度由1 800 mg/L逐渐提高到13 520 mg/L,运行60 d后系统COD去除率最低为45%,并且保持稳定,出水pH值和碱度相对比较稳定,污泥明显呈颗粒状,反应器启动完成。反应器可以在短时间内重新启动,污泥活性很快得到恢复。 相似文献
958.
采用同时硝化反硝化对某垃圾填埋场渗滤液进行处理,并对有机物去除效果进行分析。实验结果表明,反应器对渗滤液中COD、氨氮、总氮和部分有机物具有较好的处理效果,COD、氨氮和总氮的平均去除率为82.34%、99.82%和65.31%。GC-MS分析总共检测出53种主要有机污染物,其中邻苯二甲酸二丁酯等29种有机物的去除率达100%,乙基苯等5种有机物的去除率高于90%,邻苯二甲酸二异辛酯等8种有机物的去除率介于60%和90%之间,此外还有4-苯基戊醇等5种有机物去除率低于60%。反应器内存在亚硝氮途径的脱氮反应形式。 相似文献
959.
K.W. Pi L.X. Gao M.X. Fan W.Q. Gong D.J. Wan 《Process Safety and Environmental Protection》2009,87(5):336-342
The municipal landfill leachate was treated in a hydrolysis–acidification reactor (HAR)/aerobic bio-contact oxidation reactor (ABOR) following a pretreatment with ultrafiltration (UF) membrane. Experiments were conducted continuously for 44 days at a constant flow rate of 20 l d−1 and organic loading rates (OLRs) from 0.75 to 1.5 kgCOD m−3 per day. The results showed that COD of the leachate steadily decreased from 20,015 mg l−1 to less than 3000 mg l−1, and NH4-N decreased from 368.6 mg l−1 to 259.3 mg l−1 in the UF process. The COD and NH4-N removal efficiency of HAR was 56.7% and 27.7%, and that of ABOR was 94.6% and 86.7%, respectively. The total COD and NH4-N removal efficiency reached 99.6% and 93.2%, respectively. UF and HAR played a critical role in raising the biodegradability of the landfill leachate, while ABOR had an important function on removing the dissolved NH4-N in leachate. 相似文献
960.
采用摇动床生物膜反应器,在中国北方冬春季5~10℃的低温条件下,以城市生活污水处理厂的二级处理出水为水源进行了工作体积4.8 m3的反应器深度处理的中试研究。中试过程以COD、NH4+-N和浊度的去除率为考察指标。实验结果表明:反应器对生活污水深度处理的合适的工艺参数为进水温度10℃,停留时间(HRT)4.8 h,气水比4∶1,曝气量4 m3/h,水流量1.0 m3/h,采用每间隔4 h曝气4 h的间歇式曝气方式;在低温条件下,对污水的COD和NH4+-N的去除率分别为30%和50%,而对浊度的去除率较低。中试表明,摇动床生物膜反应器可应用于中国北方冬春季低温条件下对水中COD和NH4+-N的去除。 相似文献