主流条件下两级式PN-ANAMMOX工艺的高效能脱氮过程

中低温条件下采用两级式PN-ANAMMOX工艺对低浓度NH_4~+-N(50 mg·L~(-1))污水进行高效脱氮过程研究.结果表明,20~14℃范围内PN-ANAMMOX工艺的脱氮负荷和TN去除率可分别维持在0.6 kg·(m~3·d)~(-1)和80%以上;两级式PN-ANAMMOX工艺在限NO_2~--N和限NH_4~+-N两种模式下均可保持稳定运行,其中限NH_4~+-N运行模式为污水极限脱氮需求奠定了良好基础.当温度降至12℃时,PN-ANAMMOX工艺的脱氮负荷下降至0.5 kg·(m~3·d)~(-1)左右,低温使得ANAMMOX反应成为工艺脱氮的限速步骤而对PN无明显影响.ANAMMOX污泥比PN颗粒污泥具有更高的温度敏感性,二者活性的温度系数分别为1.056和1.172.综上可知,对于低温条件下运行的两级式PN-ANAMMOX工艺,ANAMMOX菌体数量及活性是决定工艺脱氮负荷的步骤,而PN出水中基质组成(即NO_2~--N/NH_4~+-N之比和NO_3~--N浓度)是控制工艺脱氮效果的环节.基于上述结果,提出两级式PN-ANAMMOX工艺主流条件下实现高效能脱氮的分级分离式调控策略.     

Development of methods for establishing nutrient criteria in lakes and reservoirs: A review

Nutrient criteria provide a scientific foundation for the comprehensive evaluation, prevention,control and management of water eutrophication. In this review, the literature was examined to systematically evaluate the benefits, drawbacks, and applications of statistical analysis,paleolimnological reconstruction, stressor-response model, and model inference approaches for nutrient criteria determination. The developments and challenges in the determination of nutrient criteria in lakes and reservoirs are presented. Reference lakes can reflect the original states of lakes, but reference sites are often unavailable. Using the paleolimnological reconstruction method, it is often difficult to reconstruct the historical nutrient conditions of shallow lakes in which the sediments are easily disturbed. The model inference approach requires sufficient data to identify the appropriate equations and characterize a waterbody or group of waterbodies, thereby increasing the difficulty of establishing nutrient criteria. The stressor-response model is a potential development direction for nutrient criteria determination, and the mechanisms of stressor-response models should be studied further. Based on studies of the relationships among water ecological criteria, eutrophication, nutrient criteria and plankton, methods for determining nutrient criteria should be closely integrated with water management requirements.     

金属矿山掘进巷道新型通风除尘系统研究与应用

为了减少掘进巷道的粉尘危害,以某金属矿掘进工作面为研究对象,经过现场调研和理论分析,研究开发了1种适合掘进巷道的新型通风除尘系统。介绍了新型通风除尘系统的结构和工作原理,并将该通风除尘系统应用于掘进巷道的粉尘治理,对该系统在掘进巷道的应用效果进行现场测定。研究结果表明:该通风除尘系统将压风筒布置在巷道中心位置的顶部,抽风筒布置在巷道两侧的呼吸带高度,使得掘进工作面的风流位置控制在1.5 m之下,保障了作业人员的职业健康。系统的湿式除尘风机对掘进巷道粉尘除尘效率达到了91%以上,彻底解决了掘进巷道粉尘污染问题。同时该系统能够实现按需通风除尘,净化后的风流可以循环利用,节能效果显著,在金属矿山掘进巷道生产系统具有较好的应用前景。     

水解酸化-地下渗滤技术处理生活污水的工艺研究

为优化水解酸化-地下渗滤系统(Hydrolytic Acidifi-cation-Subsurface Wastewater Infiltration System,HA-SWIS)工艺参数,提高分散式污水处理效果,通过控制HA水力停留时间(Hydraulic Retention Time,HRT)、搅拌速度、SWIS水力负荷(Hydraulic Load Rate,HLR)及干湿比,考察系统COD、NH4+-N、TN和TP的去除效果。由于温度控制在18～22℃,忽略温度对COD、NH4+-N、TN和TP去除效果的影响。结果表明,随优化参数改变,HA-SWIS联合工艺去除污染物效果存在显著性差异(p <0. 05)。当HA搅拌速度为15 r/min、HRT为2 h时,SWIS的HLR为0. 08～0. 12 m3/(m2·d),干湿比为1∶1～2∶1时,联合工艺对COD、NH4+-N、TN和TP的去除效率最高,分别为92. 0%、78. 6%、65%和92. 7%。该装置占地小,基建费用低,无需药剂投入,每吨水处理费用0. 46元/t,处理水质可回用,满足景观水要求(GB/T 18921—2002),适用于管网不完善地区。     

湿式旋流弦切除尘器性能实验研究

旋流弦切除尘器作为一种新型湿式除尘器,具有良好的特性。本文在所建立的实验系统上,按湿式除尘性能测试的相关规范,研究了除尘风速、弦切速度与除尘器效率和压力损失间的关系。实验结果显示:在液气比为定值时(0.05 L/m~3),在实验风速范围内,除尘效率存在极值;压力损失符合流体力学的局部阻力规律,并拟合出了除尘器的局部阻力系数。     

黄水为碳源的颗粒污泥除磷机理研究

颗粒污泥作为近年来备受关注的一种生物处理技术,具有结构密实、沉降性好、生物相丰富且活性高等优点。为了了解好氧颗粒污泥除磷机理,以黄水为碳源的同步脱氮除磷颗粒污泥为研究对象,研究颗粒污泥的物理特性、除磷特性,重点研究颗粒污泥中磷的形态及含量,同时研究不同方法对颗粒污泥胞外聚合物(EPS)的提取效果及其对磷去除的影响,揭示该颗粒污泥的除磷机理,为城市污水利用同步脱氮除磷颗粒污泥实现高效低耗除磷提供理论与技术支持。     

某炼铁厂炉顶除尘系统的风量调整与仿真分析研究

某炼铁厂炉顶除尘设备运行中各吸尘点风量失衡,造成除尘系统不能发挥应有的作用.通过对除尘系统各吸尘点风量及阻力、除尘器性能、风机性能等参数进行测试,并利用Fluent对系统内流场分布进行仿真与评估、对系统阻力平衡点进行分析,重新调整各个调节阀的开度,优化系统各吸尘点风量分布.调整后,不仅使系统达到现有条件下最佳除尘效果,而且找出了除尘系统设计及运行缺陷,提出了可行的解决方案.     

粒径控制对好氧颗粒污泥处理高含氮废水的影响

采用序批式反应器(SBR),以不同的缺氧搅拌时长来控制颗粒污泥粒径,探究不同粒径的好氧颗粒污泥系统对高浓度氨氮废水的处理特性。研究表明不同控制策略下的4个反应器(R1~R4)分别得到的主要粒径分布为0.4~0.6,0.6~0.8,0.6~0.8,1.0~1.2 mm;系统稳定阶段氨氮平均去除率分别为83.6%、79.4%、77.7%和73.1%。此外,好氧颗粒污泥系统处理高氨氮废水时,颗粒粒径最小的反应器(R1)在氨氮、总氮和磷酸盐方面具有较好的去除效果,但其颗粒污泥的物化性能并没有体现出较高优势。     

Hp-β-环糊精包络臭氧氧化去除水中PPCPs研究

为提高臭氧的稳定性,采用臭氧化Hp-β-环糊精溶液的方法对臭氧进行包络。考察了臭氧/Hp-β-环糊精包络物的氧化特性,臭氧化量和Hp-β-环糊精浓度对臭氧/Hp-β-环糊精包络物氧化能力的影响,并研究了臭氧/Hp-β-环糊精包络物对二级出水中添加的10种药品和个人护理用品(PPCPs)的去除效果。结果表明:臭氧/Hp-β-环糊精包络物具有持续的氧化能力,增加臭氧化量或Hp-β-环糊精浓度可显著提升臭氧/Hp-β-环糊精包络物的氧化能力。臭氧/Hp-β-环糊精包络物有较强的氧化性;向0.7 g/L的Hp-β-环糊精溶液中通入6 mg臭氧后,PPCPs的去除率为50%~70%,去除率受PPCPs分子结构影响。臭氧/Hp-β-环糊精包络物氧化可与其他氧化技术联合应用于污染物去除或用作臭氧化后的持续氧化。     

Simultaneous denitrification and denitrifying phosphorus removal in a full-scale anoxic–oxic process without internal recycle treating low strength wastewater

Performance of a full-scale anoxic-oxic activated sludge treatment plant(4.0×10~5 m~3/day for the first-stage project) was followed during a year.The plant performed well for the removal of carbon,nitrogen and phosphorus in the process of treating domestic wastewater within a temperature range of 10.8℃ to 30.5℃.Mass balance calculations indicated that COD utilization mainly occurred in the anoxic phase,accounting for 88.2% of total COD removal.Ammonia nitrogen removal occurred 13.71% in the anoxic zones and 78.77% in the aerobic zones.The contribution of anoxic zones to total nitrogen(TN) removal was 57.41%.Results indicated that nitrogen elimination in the oxic tanks was mainly contributed by simultaneous nitrification and denitrification(SND).The reduction of phosphorus mainly took place in the oxic zones,51.45% of the total removal.Denitrifying phosphorus removal was achieved biologically by 11.29%.Practical experience proved that adaptability to gradually changing temperature of the microbial populations was important to maintain the plant overall stability.Sudden changes in temperature did not cause paralysis of the system just lower removal efficiency,which could be explained by functional redundancy of microorganisms that may compensate the adverse effects of temperature changes to a certain degree.Anoxic-oxic process without internal recycling has great potential to treat low strength wastewater(i.e.,TN 35 mg/L) as well as reducing operation costs.