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781.
利用厌氧反应器技术+高效絮凝处理造纸法烟草薄片生产废水,CODCr可从6000mg/L降到2000mg/L以下,再用去除率高达90%的SBR序批式反应器技术进行深度处理,废水经处理可达标排放(CODCr≤100mg/L)。 相似文献
782.
UASB处理高浓度硫酸盐废水启动过程污泥特性变化 总被引:6,自引:1,他引:5
跟踪比较一套处理高浓度硫酸盐污水的UASB反应器从启动驯化到稳定运行的243 d内污泥特性的变化.结果显示颗粒污泥的形成与生物活性直接影响反应器的处理效率.反应器启动初期颗粒污泥的平均粒径由种泥的1.82 mm减少至0.99 mm;随着负荷增加、水力停留时间缩短,颗粒污泥平均粒径呈逐步增长趋势.采用N2吹脱反应器内产生的H_2S,N_2流量为60 mL·min~(-1)时,颗粒污泥的平均粒径快速增长至1.51 mm;N_2流量为100 mL·min~(-1)时,颗粒污泥平均粒径呈现下降趋势;N_2连续吹脱使得反应器内不同高度污泥的平均粒径趋于接近.污泥中活性微生物的量(MLVSS)在启动初期先降后升,升至33.59 g·L~(-1)之后平稳增长到49.72 g·L~(-1),活性污泥中微生物所占悬浮固体量的比例(MLVSS/MLSS)也呈相同的变化趋势,先下降后升至0.36之后平稳升至0. 50;相关性分析表明,反应器硫酸盐还原效率与MLVSS呈显著正相关(r=0.918,p=0.003),驯化过程中SO_4~(2-)还原效率为30%~95%.电镜分析表明,接种时颗粒污泥表面粗糙,结构松散,多为丝状菌、杆菌、球菌;驯化后颗粒污泥表面光滑内部微生物结构紧密,菌群密集,多为弧菌、杆菌.硫酸盐还原反应器驯化过程中负荷、水力停留时间、反应器内水力上升流速、以及N2吹脱强度和时间都影响颗粒污泥粒径的变化;污泥中菌群组成的变化也可能是影响颗粒污泥粒径变化因素之一. 相似文献
783.
784.
一个中小型中药厂生产废水处理运行实例 总被引:1,自引:0,他引:1
采用“水解(预处理)-ABR(厌氧)-UNITANK(好氧)”工艺处理中成药废水,电气控制部分采用可编程PLC系统。废水站全天24h全自动连续运行,无人值守。进水CODo约2000~5000ms/L,出水水质达到GB8978—1996《污水综合排放标准》一级排放标准。 相似文献
785.
Bio-reduction of nitrate from groundwater using a hydrogen-based
membrane biofilm reactor 总被引:2,自引:0,他引:2
A hydrogen-based membrane biofilm reactor(MBfR) using H2 as electron donor was investigated to remove nitrate from groundwater.When nitrate was first introduced to the MBfR,denitrification took place on the shell side of the membranes immediately,and the effluent concentration of nitrate continuously decreased with 100% removal rate on day 45 under the influent nitrate concentration of 5 mg NO3--N/L,which described the acclimating and enriching process of autohydrogenotrophic denitrification bacteria.A series of short-term experiments were applied to investigate the effects of hydrogen pressures and nitrate loadings on denitrification.The results showed that nitrate reduction rate improved as H2 pressure increasing,and over 97% of total nitrogen removal rate was achieved when the nitrate loading increased from 0.17 to 0.34 g NO3--N/(m2 ·day) without nitrite accumulation.The maximum denitrification rate was 384 g N/(m3 ·day).Partial sulfate reduction,which occurred in parallel to nitrate reduction,was inhibited by denitrififcation due to the competition for H2 .This research showed that MBfR is effective for removing nitrate from the contaminated groundwater. 相似文献
786.
Haifeng Wang Ran Xu Fengting Li Junlian Qiao Bingru Zhang State Key Laboratory of Pollution Control Resource Reuse College of Environmental Science Engineering Tongji University Shanghai China. 《环境科学学报(英文版)》2010,(3)
A laboratory study was performed to assess the biodegradation of lube oil in bio-reactor with 304# stainless steel as a biofilm carrier. Among 164 oil degrading bacterial cultures isolated from oil contaminated soil samples, Commaonas acidovorans Px1, Bacillus sp. Px2, Pseudomonas sp. Px3 were selected to prepare a mixed consortium for the study based on the efficiency of lube oil utilization. The percentage of oil degraded by the mixed bacterial consortium decreased slightly from 99% to 97.2% as the concentration of lube oil was increased from 2000 to 10,000 mg/L. The degradation of TDOC (total dissolved organic carbon) showed a similar tendency compared with lube oil removal, which indicated that the intermediates in degradation process hardly accumulated. Selected mixed bacterial consortium showed their edge compared to activated sludge. Scanning electron microscopy (SEM) photos showed that biofilms on stainless steel were robust and with a dimensional framework constructed by EPS (extracellular polymeric substances), which could promote the biodegradation of hydrocarbons. The increase of biofilm followed first-order kinetics with rate of 0.216 μg glucose/(cm2·day) in logarithm phase. With analysis of Fourier transform infrared spectroscopy (FT-IR) and gas chromatography-mass spectrometry (GC-MS) combined with removal of lube oil and TDOC, mixed bacterial consortium could degrade benzene and its derivatives, aromatic ring organic matters with a percentage over 97%. 相似文献
787.
The denitrification and P-removal in the sorption-denitrification-P-removal (S-DN-P) process were carried out under various wastewater compositions. It is noted that P-removal largely depends on the wastewater composition as well to the quantity of the substrates present in wastewater fraction. Three different wastewater fractions are obtained as: raw wastewater, dissolved wastewater (obtained with filtration using 0.45 μm filter), and undissolved wastewater (i.e., infiltrate obtained by above filtration). ... 相似文献
788.
对自行研制的上流式多级厌氧反应器(UMAR)处理木薯淀粉废水的启动和运行特性进行了研究.结果表明,UMAR反应器启动周期短,易培养出活性高的颗粒污泥,经过40 d的运行,COD去除率可达84%,VSS/TSS由78%增加到90.4%.UMAR处理效率高,水力停留时间(HRT)为4 h,进水COD为6 250 mg/L,容积负荷为24 kg/(m3·d)时, COD去除率在75%以上.UMAR反应器对负荷提高、低pH冲击、进水水质的改变表现出良好的耐受能力. 相似文献
789.
NOX作为一种致命的环境污染物,是引起温室效应和光化学反应、酸雨产生的重要危害物质之一。NOX最主要排放源就是火电厂。由于传统火电厂的低氮燃烧技术已无法满足氮氧化物的排放标准。在此情况下,烟气选择性催化还原技术(Selective Catalyst Reduction,简称SCR)诞生了,这项工艺的发明有效地降低电厂氮氧化物对环境所带来的负面影响。 相似文献
790.