水质氨氮在线监测仪发展现状

主要对不同类型水质氨氮在线监测仪的方法原理、主要技术指标及目前国内外仪器型号等进行了叙述和比较。     

XHAN-90B型氨氮在线自动监测仪在环境分析中的应用

XHAN-90B型氨氮在线自动监测仪各项性能指标优越,可以准确地在线自动监测环境中不同种类的地表水和工业废水.     

水质在线监测仪在农村生活污水治理的应用与探索

农村生活污水多以就地处理方式来治理,治理设施数目多而分散,人工采样监测不能实时连续,故水质在线监测仪在"点多面广"的分散性农村污水治理系统的应用显得必要而急迫。结合自主研发的自控系统与水质监测仪的应用与推进,水质在线监测仪在柯桥区农村生活污水处理终端得以推广应用,水质在线监测仪运行状况良好。     

氨氮在线自动监测仪的现状与问题

氨氮在线自动监测仪已在我国水质自动监测系统中得到广泛应用。其生产厂家日趋成熟、相关标准逐步出台、仪器性能基本达标。但在实际应用过程中,该仪器仍有许多问题需要进一步认识与改进。本文从方法选择、干扰排除、国家标准、比对、质量控制等几个方面,分析了该仪器存在的问题,并提出了相关建议。     

在线监测氨氮浓度的电导测量方法研究

建立了适用于氨氮在线监测的干法蒸馏-电导法和湿法蒸馏-电导法。该方法是通入一定流量的气量于含氨试样中,全沸腾加热,蒸发出的氨和水蒸气一起经冷凝器后,进入酸吸收液中。酸吸收液的电导率随氨氮蒸馏液的吸收发生变化,其变化的值和样品中氨氮的浓度呈一定的比例关系。研制出的氨氮在线监测仪结构简单,运行稳定可靠,测量结果准确。     

DL 2001COD水质在线监测仪现场验收的若干问题

佛山市南海区从2004年开始筹建了重点污染源（废水）在线管理系统，2005年该区环境保护监测站在开展水质在线监测仪的验收监测时发现了一些问题，提出了改进建议。     

在线自动监测与手工分析地表水总氮的可比性研究

对比浙江省地表水水质自动监测站总氮在线监测与实验室手工方法,分析进口水质总氮自动监测仪在国内的适用性以及与手工方法的可比性。结果表明,一些国外引进的自动监测仪在国内使用时要根据我国水体的实际情况在实验条件上作一定的改进,改进后的监测数据与手工方法才具有可比性。     

江苏省环境监测现代化建设方案 ( 续 )

2.2.1.2　建设全省水质自动监测系统在市际交界断面、集中饮用水源地、太湖主要出入湖河道、长江及淮河流域的重点断面、南水北调东线江苏段等进行水质实时监控,减少污染事故的发生和因灾害带来的损失,预警饮用水源水质。今后5年,建成省级固定水质自动监测站38个,配置一批水质流动监测车。2.2.1.3　建设全省污染源自动监控系统在占全省65%COD排放量的省控重点污染源安装COD在线监测仪、pH计、污水流量计、等比例采样器;在占全省65%SO2排放量的大气重点污染源安装在线监测仪。建立省总控中心、各市分控中心,实现联网监控。2.2.2　建立遥…     

介绍一种连续自动选择硝酸盐、磷酸盐或氨的监测仪

90型监测仪是英国xALFA—LAVAL有限公司研制的水源水质先期联线监测系统.这种小型监测仪根据被测物的化学特性要求,可选用比色法或离子测定法的方式连续测定流动水样.该监测仪具有下列特点1.连续自动操作仪器的全部功能自动操作,适用于在线连续监测.当被测物的浓度超过设定浓度时,就会直接显示出来,并有完整的报警装置.     

COD在线监测仪的比对分析

以新疆某化肥有限公司污水COD在线监测仪为例,用在线监测数据与实验室重铬酸钾法测定数据进行比对分析,对污染源在线监测的比对分析方法进行探讨.通过比对,二者没有显著性差异,用在线监测仪测定COD,可节约时间,有利于对污染源的在线监控.     

Combined Non-Catalytic Reduction of NOx and SO2 by Ammonia Liquor during Staged Fluidized-Bed Combustion

Emissions of NOx and SO2 were monitored in the presence of ammonia liquor in a 0.09 m2 and 2 m high stainless-steel fluidized-bed combustor. Experiments were carried out at 2 m/s fluidizing velocity, 40% excess air, and 870 °C bed temperature. Ammonia liquor with 7% ammonia by weight was injected into the freeboard of the combustor 52 cm above the distributor through a water-cooled injector. A 65 : 34 primary/secondary air ratio was maintained throughout the investigation. Approximately 70% of NO and 20% of SO2 was reduced at an NH3/NO molar ratio of 2 : 1, respectively. However, a higher reduction in SO2 emissions (62%) was achieved at a very high NH3/NO molar ratio of 7 : 1. These experiments showed that ammonia addition did have a significant effect in SO2 reduction if injected in an excess amount. The injection of ammonia liquor combined with staged combustion was found to be very effective in reducing NOx emissions. A reduction of about 50% was achieved at an NH3/NO molar ratio of 0.6 : 1 which is also coupled with a very low level of ammonia in the flue.     

大气中NH3的光学监测技术研究进展

NH3是大气中含量仅次于NO和N2的含氮化合物,也是大气中重要的碱性气体,作为酸性污染物的中和剂,NH3越来越受到人们的重视。文章介绍了大气NH3的主要农业和非农业排放来源,并详细介绍了近年来大气NH3的光谱测量技术(光声光谱技术,量子级联激光吸收光谱技术,傅里叶红外分析技术,可调谐半导体激光器吸收光谱技术以及紫外差分吸收光谱技术)及其进展,总结并分析了这些技术的技术要点、应用领域以及在最近10年对大气NH3的测量结果和研究热点。     

纳氏试剂法检测水中低浓度氨氮存在问题分析及方法改进探讨

针对采用《水质氨氮的测定纳氏试剂分光光度法》(HJ 535—2009)测定低浓度氨氮时存在的测不准问题,研究了药剂投加量、反应时间等因素对检测结果的影响,认为低浓度氨氮下的显色反应速度过慢是测定结果不准的原因,并据此提出利用强碱调节pH的方法加速反应进程。改良后的方法可以在0.2～1.2 mg/L氨氮浓度范围内呈现良好的线性关系,相关系数r为0.999 4。该方法具有较高的准确度和精密度,有效扩大了低浓度氨氮的检测范围,在实际样品检测中的回收率为102.5%～115.0%,可为准确测定水环境和饮用水中的氨氮浓度提供一种简便易行的手段。     

靛酚蓝分光光度法测定化肥厂废水中微量氨

用靛酚蓝分光光度法测定废水中的氨，对实验中的干扰因素，最佳试剂组合，测定下降，精密度及回收率均进行了研究，结果令人满意。     

Reduction of SO2 Emissions by Ammonia Gas During Staged Combustion

To reduce SO2 emissions, ammonia gas was injected into a coal-fired fluidized-bed combustor under staged commbustion condition. The combustor was 2 m high with a 30 cm static bed height and a freeboard height of 170 cm. The ammonia gas was injected at 52 cm and 65 cm above the distributor, which had a temperature of ca. 700 °C, by an uncooled stainless-steel tube injector. The experiments investigated the effects of ammonia gas injection on sulphur dioxide emissions at staged conditions, varying the: (i) excess air level, (ii) secondary air ratio, (iii) fluidizing velocity, (iv) ammonia injection position, and (v) the ammonia : sulphur dioxide molar ratio.A maximum reduction of 66% in SO2 emissions was found at 40% excess air, 65 : 35 staging, 1.5 m/s fluidizing velocity, 65 cm injection height, and an NH3 : SO2 molar ratio of 1.2. The onset of SO2 reduction occurred at an NH3 : SO2 ratio of 0.5. The fluidizing velocity, excess air, level of staging, and ammonia injection height all have a significant influence on SO2 reduction.It is difficult to determine how the SO2 reduction varies with the operating conditions when ammonia is injected in the high temperature zone of the combustor. As sulphur oxides-ammonia reactions are low temperature reactions, the findings confirm the occurrence of reactions above the freeboard or near the exit to the cyclone.     

在线蒸馏-无人值守连续流动分析法测定污水中氨氮

采用在线蒸馏-无人值守连续流动分析法对污水中氨氮进行检测,方法在0.00~10.0 mg/L范围内线性良好,检出限为0.014 mg/L,实际样品测定的相对标准偏差为1.24%~4.15%,加标回收率为93.0%~108%,精密度和准确度均能满足污水中氨氮的测定要求。     

Spatial modelling of the probability of obtaining a detectable concentration of ammonia in Moreton Bay, Australia

Ammonia is an important water quality variable, which in excess, can be detrimental to waterways and their ecosystems. In the Ecosystem Health Monitoring Program in South-east Queensland ammonia is monitored monthly, however, often more than 50% of the ammonia observations in Moreton Bay are below detection limit, making it difficult to draw useful inferences. In this paper a clipped Gaussian random field is used to spatially model and map the probability of detectable concentration of ammonia. The methodology is applied to the Moreton Bay samples collected in February 2005. The results suggest that for this month the oceanic impacted areas have higher probability of detectable ammonia concentration than the areas closer to the main sources of anthropogenic inputs.     

常州市地表水中氨氮输移分析及对策建议

目前常州市地表水中氨氮污染已成为最突出的问题。通过近2年来的监测和调查,参考有关资料和科研成果,估算出常州市地表水中年接纳氨氮总量为17998.0t/a,其中农田径流占32%,上游行政交界来水占30%,而城镇生活污水、农村生活污水、工业废水、城镇地表径流和规模化畜禽养殖等所占比重均不足13%。并据此提出了减轻地表水中氨氮污染的对策建议。     

气相分子吸收光谱法测定地表水中氨氮

通过实验建立气相分子吸收光谱法测定地表水中氨氮的方法。方法检出限为0.020 mg/L,水样加标回收率为91.3%~100%,平行样品相对偏差为0.25%~1.43%,精密度(RSD,n=7)为0.10%。实验结果表明,该方法准确可靠、灵敏度高、操作简便,重现性好、分析速度快,适用于地表水中氨氮测定。     

南通濠河水体中非离子氨的动态变化分析

分析了濠河水体中非离子氨在不同断面、不同月份、不同年际的变化情况 ,并指出其超标的原因及控制措施