净水工艺中剑水蚤的二次繁殖及控制

为解决净水工艺中剑水蚤的二次繁殖问题,进行了生产性试验,考察了二氧化氯与常规工艺协同对剑水蚤的去除效果.指出滤池滞水区停留时间长、流速低是造成剑水蚤二次繁殖的主要原因.二氧化氯预氧化可以强化常规处理工艺对剑水蚤的去除,当二氧化氯投加量为2 mg/L时,可以有效控制剑水蚤的二次繁殖.     

Preliminary Study on Biological Control of Cyclops of Zooplankton in Drinking Water Source

An ecological project called fish biomanipulation, other than the conventional fishery culture tech-nique, was put forward in this paper for the excess propagation control of Cyclops. The control effects on Cyclops of four species of fish were investigated experimentally at stocking density of 30 g per cubic meter of water. The experimental results showed that the food habit of the fish had significant influence on the biological control of Cyclops. The propagation of Cyclops could be controlled effectively and also the water quality was improved simultaneously by stocking the filter-feeding fishes, such as silver carp and bighead carp. Whereas, herbivorous Ctenopharyngodon idellus and omnivorous Cyprinus carpio had no obvious biological effects on controlling the growth of Cyclops and restoring water quality. The results further proved that under condition of proper poly-culture density of silver carp and bighead carp, the number of Cyclops might be controlled at very low level and the eutrophication might be abated by removing the nutrients from water body.     

河北应急水源的预臭氧化工艺研究

南水北调的应急工程是从河北四水库调水进京,四水库水源水质与密云水库水质相差较大.为了保证河北水进京后水厂工艺运行的稳定性,根据水厂现行工艺(混凝-沉淀-煤砂过滤-活性炭过滤)增加预臭氧在河北黄壁庄水库进行适应性研究.试验结果表明:在投加臭氧1.5～2.6 mg/L后炭出水基本无味;试验条件为:臭氧浓度0.4 mg/L,接触时间8 min时,预臭氧能够将剑水蚤杀死去除;预臭氧后系统对有机物去除效果较好,且沉后藻类去除率达到80%以上,煤滤池出水藻类低于2万个/L;中试系统煤滤池出水和炭滤池出水溴酸盐浓度均小于5 μg/L,因此臭氧氧化后不存在溴酸盐副产物超标的风险.同时,建议在河北水进京前测定水中MIB浓度,适时调整臭氧投加量,在有必要的情况下考虑增加粉末活性炭预吸附.     

水中剑水蚤类浮游动物去除技术发展状况研究

水源污染及水体富营养化导致以桡足类剑水蚤为代表的浮游动物的大量繁殖,由于其不能被有效去除,致使在水厂乃至入户水中仍有出现,这是给水处理中出现的一个新问题,本文从生态学的角度对其生理特性进行了阐述,为研究提供了可靠的科学依据．并从国内外水处理现状入手．对现有去除技术进行分析探讨,并在此基础上提出了更为安全有效的去除方案．相信通过更加深入的研究和设计,必将完善水处理工艺,从而达到彻底在水处理过程中安全有效的去除剑水蚤类浮游动物、保证饮用水质安全的目的．     

氧化剂对剑水蚤类浮游动物的灭活效能及影响

为解决水源水中孳生的水蚤类浮游动物难以被常规的水处理工艺有效地去除,困扰水厂正常生产运行的问题,进行了几种水处理氧化剂——氯气、二氧化氯、臭氧、高锰酸钾对水体中剑水蚤类浮游动物灭活效果的试验研究。并对二氧化氯预氧化与水处理澄清过程的协同除蚤效能进行了考察．结果表明,与其他3种药剂相比,二氧化氯对剑水蚤具有更显著的灭活作用,在较低的投药量(1．Omg／L)下就可以达到100％的灭活率;灭活效果受水体pH值、有机物含量的影响较小．在采用预投二氧化氯的除蚤工艺中,二氧化氯预氧化与水处理澄清过程的协同作用将会进一步提高除蚤的效果。     

Real‐time wind field reconstruction from LiDAR measurements using a dynamic wind model and state estimation

The use of light detection and ranging (LiDAR) instruments offer many potential benefits to the wind energy industry. Although much effort has been invested in developing such instruments, the fact remains that they provide limited spatio‐temporal velocity measurements of the wind field. Moreover, LiDAR measurements only provide the radial (line‐of‐sight) velocity component of the wind, making it difficult to precisely determine wind magnitude and direction, owing to the so‐called ‘cyclops’ dilemma. Motivated by a desire to extract more information from typical LiDAR data, this paper aims to show that it is possible to accurately estimate, in a real‐time fashion, the radial and tangential velocity components of the wind field. We show how such reconstructions can be generated through the synthesis of an unscented Kalman filter that employs a low‐order dynamic model of the wind to estimate the unmeasured velocities within the wind field, using repeated measurement updates from typical nacelle‐mounted LiDAR instruments. This approach is validated upon synthetic data generated from large eddy simulations of the atmospheric boundary layer. The accuracy of the wind field estimates are validated across a variety of beam configurations, look directions, atmospheric stabilities and imperfect measurement conditions. The main outcome of this paper is a technique that offers the potential to accurately reconstruct wind fields from LiDAR data, overcoming the cyclops dilemma in the process. The ultimate aim of this research is to provide reliable gust detection warning systems to offshore construction workers, in addition to accurate wind field estimates for use in preview turbine pitch control systems. © 2014 The Authors. Wind Energy published by John Wiley & Sons Ltd.     

除蚤剂对活性炭上微生物的影响

从对生物量和微生物耗氧速率的影响方面，考察了盐水、氨水、氯和氯胺等四种除蚤剂对活性炭上微生物的影响。小试结果表明，投加4种药剂虽使得活性炭上的生物量降低1～2个数量级，但基本上能维持在10^6数量级，即这种影响在可接受的范围之内；药剂对活性炭上微生物的活性具有抑制作用。选取盐水和氨水做对活性炭上微生物影响的生产性试验，结果表明：投加20g／L的盐水和10mg／L的氨水后，活性炭上的生物量降低了40％～60％，但都能维持在10^6数量级，因此认为药剂对活性炭上生物量的影响可以忽略不计；同时，微生物的活性随着过滤的进行而逐渐得到恢复，用盐水浸泡过的滤池需要5d的恢复时间，而用氨水浸泡的滤池只需2～3d。可见，采用盐水或氨水浸泡活性炭滤池来控制剑水蚤的生长是可行的。     

水处理工艺中浮游甲壳动物的控制

浮游甲壳动物(剑水蚤)在水库水中的孳生给水处理工艺带来了新的问题，同时也给饮用水的安全带来了威胁。分析了剑水蚤大量繁殖的原因，结合水厂的生产实际提出了相应的控制方法和水源保护方面的一些建议，认为应加强对水源水中水生生物的监测。