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621.
稻草末固定白腐菌处理染料废水的研究   总被引:11,自引:1,他引:11  
对采用微电解-白腐菌生物降解-石炭絮凝系统处理活性染料废水进行了研究。试验结果表明,废水的COD去除率和色度除率均达到95%以上,出水水质符合废水排放标准。  相似文献   
622.
在现代建筑节能体系中,暖通空调系统具有十分重要的作用。节能技术之研究与运用,是暖通空调系统节能的组成部分之一,而政府部门的关心与重视,则能充分节能,产生较为显著的社会效益,促进社会经济的快速发展。文章从不断提高系统的控制水平、应用变频技术实现节能效果、推广使用可再生能源的空调系统、尽量减少输送系统产生的动力能耗、使用新型节能的健康空调运行方式等五个方面探讨了暖通空调系统的节能措施。  相似文献   
623.
应用氧化絮凝复合床降解废水中的阴离子表面活性剂,系统地研究了各种主要的物理化学因素;催化剂种类、填料颗粒粒度、槽电压、电极间距离、压缩空气流量、试样的浓度、酸度、电导率和处理时间等对阴离子表面活性剂去除效果的影响,找到了相关的影响规律,确定了最佳的物理化学条件,实验结果表明,阴离子表面活性剂的去除率在95%以上,出水的水质可以达到国家的排放标准。  相似文献   
624.
采用混凝气浮+SBR生化法处理某化学药剂生产企业废水,工程应用实践表明,混凝加药和气浮处理可有效去除废水中的油和非溶解性 COD ,COD 总去除率达到94.3%,出水达到企业排放要求。  相似文献   
625.
三种常见混凝机理为主导条件下絮体特性研究   总被引:2,自引:0,他引:2       下载免费PDF全文
以模拟低浊微污染水为原水,硫酸铝[Al2 (SO4)3]为混凝剂,考察了3种常见混凝机理(电性中和、吸附架桥和网捕卷扫)为主导条件下絮体的成长过程、二维边界分形维数(Dpf)和比表面积及其与混凝效果的相关性.结果表明:吸附架桥为主导机理下絮体最大增长速率S (0.951)最快,达到稳定后絮凝指数FI最大(3.7%),二维边界分形维数Dpf最大(1.587),絮体呈块状且絮体间出现孔状间隙,比表面积介于网捕卷扫和电性中和之间[网捕卷扫(83.646m2/g)>吸附架桥(98.808m2/g)>电性中和(116.046m2/g)];FI值、S及Dpf变化与浊度去除率相关性较好,其相关系数分别达0.979、0.982和0.963,同时比表面积大的絮体吸附容量大,有机物的去除率高.  相似文献   
626.
采用吸附法、七铝酸十二钙法、石灰-氯化铝絮凝沉淀法对矿山循环水中高浓度SO24-的脱除进行研究。结果表明:单纯采用吸附法来处理废水,处理后水中的SO24-远不能达到工业用水标准;实验室制备的七铝酸十二钙对SO24-的去除效果不理想,仅为35%,也无法达到工业用水标准;采用石灰-氯化铝絮凝沉淀法处理废水时,当Al3+投加量为420mg/L,pH值为11时,去除率高达90%以上,可使废水中的SO24-质量浓度从1 800 mg/L降至200mg/L以下,完全可循环回用于矿山的选矿和采矿生产。  相似文献   
627.
• A way for overflow control based on on-site coagulation/flocculation was proposed. • Coagulant and flocculant dose were optimized based on pollutant removal performance. • Settling time of 5 min is enough in a proper transmission distance. • Fast removal of particulate pollutants could be achieved under varied flow. The pollution caused by wet weather overflow in urban drainage systems is a main factor causing blackening an odorization of urban rivers. The conventional overflow treatment based on coagulation/flocculation in terminal drainage systems requires relatively large space and long retention time demand that makes it not applicable in crowded urban drainage systems or under heavy rains. On-site coagulation/flocculation in terminal drainage pipes was proposed in this study which was aimed to transfer the coagulation/flocculation process to the inside of pipes at the terminal drainage system to save space and reduce the retention time of the coagulation/flocculation process. The optimized dose of chemicals was studied first which was 80 mg/L of coagulant and 0.8 mg/L of flocculant. Settling for only 5 min can remove most of the pollutants at 406.5 m of transmission distance. In addition, the relation of wet weather overflow rate and concentration of pollution load on the on-site coagulation/flocculation process was investigated, which indicated that high removal of pollutant was gained at a large range of flow velocity and pollutant concentration. Finally, the study confirmed electric neutralization, bridging, and net capture as the major mechanisms in this process, and further optimization was proposed. The proposed process can reduce much turbidity, chemical oxygen demand, and total phosphorous, but hardly remove soluble ammonia and organics. This work provides scientific guidance to address wet weather overflow in terminal drainage pipes.  相似文献   
628.
SSR addition upgraded VFAs production from WAS. Structure modification by pretreatments led to performance distinctions. Distinctions in microbial community was observed by pretreatments selection. Up to 0.49‒0.65 billion €/year of market value potential was preliminary estimated. Conditioning of extra carbon sources has been widely reported to facilitate fermentation of waste activated sludge (WAS). Soy sauce residue (SSR) was a relatively untapped carbon source for sludge conditioning. This batch study aimed to evaluate the possible implementation of SSR for volatile fatty acids (VFAs) production from WAS. To upgrade the bioavailability of feedstock, three typical pretreatment methods were conducted, i.e., ammonium hydroxide (AH), sulfuric acids (SA) and thermal assisted alkaline (TA). AH pretreated test (AH-PT) outperformed due to a relatively strong structure decomposition of cellulosic materials as revealed by infrared spectroscopic analysis and crystal index. As a result, performed a high hydrolysis rate of 4449 mg COD/d, 1.12-1.23-fold higher than that in TA and SA pretreated tests (TA-PT and SA-PT), and 7.8-fold higher than that in the Control test. Meanwhile, a volatile fatty acids (VFAs) contribution of 401.2 mg COD/g SSR∙L and a maximum acidification rate of 3.59 d-1 was recorded, with a high sum proportion of mall molecular acetic and propionic 82.2%, 11% ‒70% increase over the other three tests. Besides, speciation process characterized with functional genus differentiation was identified by microbial diversity and distribution investigation and canonical correspondence analysis (CCA). Finally, a potential market value of 0.49‒0.65 Billion €/year was preliminary estimated, showing promise of resource recovery from both WAS and SSR instead of extensive disposal.  相似文献   
629.
邹华  潘纲  陈灏 《环境科学》2005,26(2):148-151
研究了水体的离子强度对粘土和壳聚糖改性粘土絮凝去除铜绿微囊藻的影响 .离子强度的增加有利于粘土对藻类的絮凝去除 .与一般粘土除藻相反 ,壳聚糖改性粘土却在离子强度低的条件下具有更好的除藻效果 ,是适合在湖泊 ,水库和江河等淡水 (低含盐量 )水体中应用的应急除藻技术 .当离子强度从 0.17mol/L降到 0mol/L时 ,海泡石除藻率从 90 %以上降为 70 %以下(投加量700mg/L) ,而壳聚糖改性海泡石的除藻率却从 70%左右升至 95% (投加量仅为 11mg/L) .用粘度法研究了壳聚糖改性海泡石的絮凝机理 ,发现相对低的离子强度更有利于壳聚糖分子链上阳电荷的相互排斥作用 ,有利于壳聚糖分子链的舒展 ,从而可以充分发挥架桥网捕作用 ,利于絮凝除藻 .  相似文献   
630.
With the random movement of silica gel beads in a conical fluidized bed, micro-vortices resulting from the fluidization promoted the collision and aggregation of suspended fine kaolin powders. The abatement efficiencies of the suspended fine solids under several hydrodynamic conditions were studied, and a suitable control strategy for operating the conical fluidized bed flocculators was identified. The suspended solids abatement efficiency was found to increase with increasing Camp Number and flocculation time (T), but decreased with the increase of velocity gradient (G) within the range studied in this research (165.1–189.6 s-1). The abatement efficiencies were all more than 60% at the range of G = 165–180 s-1 and T = 15–33 s at an initial kaolin solid concentration of 150 mg·L-1, polymer aluminum chloride dosage of 60 mg·L-1 and sedimentation time of 20 min. However, the formation of flocs was influenced by the liquid backmixing. Excessive backmixing caused the breakup of flocs and resulted in difficulty for the fine powders to aggregate and sediment to the reactor bottom. The results of the calculated fractal dimension and measured free sedimentation velocity of flocs obtained at different runs showed similar flocs properties, and indicated an easy control strategy for sedimentation of the flocs.  相似文献   
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