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Anaerobic co-digestion of food waste and FOG with sewage sludge – realising its potential in Ireland
Olumide Wesley Awe Yaqian Zhao Ange Nzihou Doan Pham Minh Nathalie Lyczko 《The International journal of environmental studies》2018,75(3):496-517
The severe environmental pollution in many countries is caused by indiscriminate discharge of large quantities of food waste (FW), fat oil and grease (FOG) and sewage sludge (SS) to the environment. There are many possible treatment routes, but anaerobic digestion (AD) is now well accepted for treating several kinds of organic wastes. But AD of FW alone presents some operational challenges because of substrates and variability. Anaerobic co-digestion of two or more substrates is better than single substrate digestion. This can use a plant’s unused capacity, in line with the trend to renewable energy. Co-digestion technology, although well established in many European countries, is still in its infancy in Ireland. There are problems with different regulatory arrangements. They should be resolved. The paper reviews anaerobic co-digestion technology is reviewed, with special focus on possible application in Ireland. 相似文献
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Biosolids reduction model by return activated sludge ozonation was validated by simulating nitrification data compiled from our pilot-scale and the literature studies. Then, a global sensitivity analysis (GSA) was performed to identify influential and non-influential parameters for biosolids reduction efficiency, change in specific nitrification activity (SNA), and alteration to expected nitrification stability. In general, the model outputs were sensitive to operational and ozone reaction parameters, but not to biochemical parameters. For operational parameters, mainly temperature and initial solids retention time (SRT) influenced all model outputs. For biosolids reduction, increase in the degradability of the influent COD decreased the reduction efficiency. For SNA, the changes were highly dependent on the influent TKN/COD ratio. Our findings also imply that the stability of the nitrification process in ozonated systems should be enhanced at constant MLVSS for warm temperatures, but could be reduced at temperatures below 12 °C and aerated SRTs below 10 days. 相似文献
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用于制备膨体颗粒调剖剂的含油污泥除油技术研究 总被引:1,自引:0,他引:1
利用含油污泥制备膨体颗粒调剖剂用于调剖堵水是一种新的污泥资源化技术,研究了含油污泥的预处理方法,尤其是除油技术。分别使用热水酸洗、热水酸洗/除油剂对污泥进行了除油试验,并以干泥含油率为指标考察了pH值、水与泥质量比、除油剂用量对除油效果的影响。试验结果表明,在水与泥质量比为2.0、pH值为6.0、45℃条件下,用矿化水热水酸洗可使干泥含油率从31.5%降至19.4%。同样条件下,除油剂用量为40.0mg/L时,热水酸洗/除油剂处理能使干泥含油率进一步降至11.2%。聚合试验结果表明,经热水酸洗/除油剂处理后的污泥能够聚合得到胶块强度高、膨胀倍数高的膨体颗粒调剖剂。 相似文献
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Jean-Fran?ois Blais Nathalie Meunier Guy Mercier Patrick Drogui Rajeshwar Dayal Tyagi 《Canadian Metallurgical Quarterly》2004,130(5):516-525
This research is related to a preindustrial pilot scale study of the performance of the simultaneous sewage sludge digestion and metal leaching (SSDML) process for decontamination and stabilization of sewage sludge. Ten batch tests were carried out in two 4?m3 bioreactors under various conditions of operation. Results indicated that the addition of 1.0 to 1.5?g?S0/L, which is the equivalent of approximately 30 to 50?kg?S0 per tons dry sludge, is sufficient to obtain conditions of acidity (pH<2.5) and oxido-reduction potential greater than 500 mV necessary for an effective solubilization of toxic metals. The final average of metal solubilization in the output sludge during the SSDML process varied in the following ranges: 25–78% Cd, 9–32% Cr, 48–100% Cu, 77–99% Mn, 15–53% Ni, 12–47% Pb, and 66–100% Zn. The N, P, and K contents were also preserved in the decontaminated sludge. Moreover, the use of low concentrations of elemental sulfur makes it possible to obtain decontaminated sludge with a low total sulfur content (1.4–1.5% S) compatible with agricultural use. The suspended solids removal calculated for the SSDML process was slightly lower, (2.5±0.4)% volatile suspended solids per day, than those reached using standard aerobic digestion. Finally, the SSDML process was found to be effective in removing bad odors and in the destruction (99–100%) of indicator bacteria. 相似文献
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Rats exposed to a footshock show conditional fear when reexposed to the shock context. Immediate presentation of shock after placement in the context significantly reduces this fear. Preexposure to the context in the absence of shock, coupled with a minimum preshock interval during training, overcomes this immediate shock deficit. Because rats learn about the context during preexposure and express that learning after being reinforced, the context preexposure effect is an aversive analogue of latent learning. The authors examined the effect of the N-methyl-D-aspartate (NMDA) receptor antagonist D,L-2-amino-5-phosphovalerate (APV) on the facilitatory effect of context preexposure. Rats were preexposed to a chamber after APV administration. The next day they were placed in the same chamber without drug and received shock 35 s later. APV blocked the facilitatory effect of preexposure. Therefore NMDA receptors are important for contextual latent learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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户式中央空调的节能研究 总被引:3,自引:1,他引:2
蔡颖玲 《制冷空调与电力机械》2004,25(5):65-68
对户式中央空调系统节能问题作了研究,从住宅建筑空调负荷的计算特点和方法、系统主机容量的确定、末端设备的选择到系统调节特性等诸多方面,综合考虑,并结合实际工程,阐述了影响户式中央空调能量消耗的各种主要因素和改进措施. 相似文献