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231.
目前,饮用水污染严重,常规工艺处理出现了水质不能达标的现象.本文主要研究在常规工艺增加预臭氧-活性炭过滤工艺,对不同的预臭氧投加量进行实验.结果表明:预臭氧投加量,对工艺各单元的处理效果有一定关系,随着投加量的增加,各单元对浊度、CODMn、UV254的去除呈现增大后趋于平缓甚至下降的趋势,而最佳臭氧的投加量为0.65 mg/L.为实际预臭氧-活性炭过滤工艺的运行提供指导.  相似文献   
232.
The removal of the natural organic matter present in coffee processing wastewater through chemical coagulation-flocculation and advanced oxidation processes (AOP) had been studied. The effectiveness of the removal of natural organic matter using commercial flocculants and UV/H202, UV/O3 and UV/H2O2/O3 processes was determined under acidic conditions. For each of these processes, different operational conditions were explored to optimize the treatment efficiency of the coffee wastewater. Coffee wastewater is characterized by a high chemical oxygen demand (COD) and low total suspended solids. The outcomes of coffee wastewater treatment using coagulation-flocculation and photodegradation processes were assessed in terms of reduction of COD, color, and turbidity. It was found that a reduction in COD of 67% could be realized when the coffee wastewater was treated by chemical coagulation-flocculation with lime and coagulant T-1. When coffee wastewater was treated by coagulation-flocculation in combination with UV/H2O2, a COD reduction of 86% was achieved, although only after prolonged UV irradiation. Of the three advanced oxidation processes considered, UV/H2O2, UV/O3 and UV/H2O2/O3, we found that the treatment with UV/H2O2/O3 was the most effective, with an efficiency of color, turbidity and further COD removal of 87%, when applied to the flocculated coffee wastewater.  相似文献   
233.
针对孚日家纺水厂出现的处理效果不理想这一问题,通过设计烧杯搅拌实验,研究不同混凝剂及与助凝剂PAM联用对低浊水浊度处理的影响。结果表明,单独采用聚合氯化铝铁PAFC比聚合氯化铝PAC混凝效果好,而与PAM联合使用比单独采用一种混凝剂的处理效果显著。从经济方面,对硫酸铝AS和氯化铁FC进行了试验分析,得出了硫酸铝AS与PAM联用,有可靠的除浊效果。  相似文献   
234.
This article aims to describe the influence of di use pollution on the temporal and spatial characteristics of natural organic matter (NOM) in a stratified dam reservoir, the Daecheong Dam, on the basis of intensive observation results and the dynamic water quality simulation using CE-QUAL-W2. Turbidity is regarded as a comprehensive representation of allochothonous organic matter from di use sources in storm season because the turbidity concentration showed reasonable significance in a statistical correlation with the UV absorbance at 254 nm and total phosphorus. CE-QUAL-W2 simulation results showed good consistency with the observed data in terms of dissolved organic matter (DOM) including refractory dissolved organic carbon (RDOC) and labile DOC and also well explained the internal movement of constituents and stratification phenomenon in the reservoir. Instead turbidity and NOM were related well in the upper region of the reservoir according to flow distance, gradually as changing to dissolved form of organic matter, RDOM a ected organic matter concentration of reservoir water quality compared to turbidity. To control the increase of soluble organic matters in the dam reservoir, appropriate dam water discharge gate operation provided e ective measurement. Because of the gate operation let avoid the accumulation of organic matter within a dam reservoir by shorten of turbid regime retention time.  相似文献   
235.
福州大气污染对太阳辐射等要素的影响   总被引:2,自引:0,他引:2  
福州大气污染对太阳辐射等要素的影响陈千盛(福建省气候中心,福州350001)池艳珍(福建省气象局)关键词太阳总辐射;散射辐射;能见度混浊度因子.建国以来,福州由于市区范围不断扩大及工业发展,人口和车辆与日俱增,空中尘埃量随之增多,空气日益恶浊.这种状...  相似文献   
236.
利用正硅酸乙酯(TEOS)、二乙氧基二甲基硅烷(DEDMS)和γ-氨丙基二乙氧基甲基硅烷(APDES)3种硅烷偶联剂作为有机硅源,制备了共价键型有机硅铝复合絮凝剂,研究了共价键型有机硅铝复合絮凝剂处理浊度水、色度水、含油废水以及垃圾渗滤液膜浓缩液的效果。结果表明,3种共价键型有机硅铝复合絮凝剂具有优良的除浊脱色性能,其除油效果远远优于无机高分子絮凝剂。对于垃圾渗滤液膜浓缩液,共价键型有机硅铝复合絮凝剂可以去除常规絮凝剂无法去除的物质,显著降低出水COD。3种共价键型絮凝剂中,以TEOS为硅源的共价键型絮凝剂除浊效果最佳,以APDES为硅源的共价键型絮凝剂除油和去除COD效果最佳。共价键型有机硅铝复合絮凝剂在含油废水和高浓度有机废水的深度处理方面有很好的应用前景。  相似文献   
237.
Abstract

Small-scale miners often engage in environmentally damaging activities, are subject to poor safety conditions, and utilize inefficient mineral extraction technologies. Here, we explore environmental impacts to surface waters from regional artisanal small-scale gold placer mining operations conducted in iron and aluminum-rich saprolites found within the lateritic, interior Amazon rainforest of Suriname. Heavy equipment was utilized to release gold from its host material followed by amalgamation and gravity separation. In contrast with background tributary recordings, streams adjacent to these gold mining operations consistently contained turbidity measurements that exceeded United States’ EPA guidelines for aquatic species of 50 nephelometric turbidity units and were typically in the hundreds to thousands of units. Turbidity was further heightened in association with precipitation events. Mercury played a prominent role in whole ore amalgam concentration practices. Freshwater fish from the region were found to harbor mercury that encroached upon public health criteria. Dissolved phase metals present further ecotoxicological challenges to the region, but their association with mining activities was less clear. These findings collectively reveal that small-scale placer gold mining practices in the Surinamese rainforest result in an increase of suspended sediments and release of mercury into waterways that could impact communities that depend upon local fisheries.  相似文献   
238.
活性炭深床滤料浮滤池是一种新型的给水处理组合工艺,它的特点是:气浮过滤一体化;活性炭深床过滤;常规处理和深度处理一体化;运行方式灵活。以直接过滤方式运行处理密云低温低浊水,效果理想,对浊度、色度和嗅味的去除效果显著,对有机物具有一定的去除作用。  相似文献   
239.
ABSTRACT: Calcium carbonate precipitate, known as “whiting,” forms in a large number of hard water lakes and reservoirs, and thus contributes to turbidity measurements in these systems. Here we document the occurrence of “whitings,” and the associated impact on turbidity, in Otisco Lake, New York. A simple, potentially broadly applicable, technique, measurement of turbidity before and after acidification, successfully quantified this component of turbidity in the lake. Calcium carbonate represented 32 percent of the turbidity in the upper waters of Otisco Lake for a three-month period, and at times was as much as 70 percent. Routine monitoring of this component of turbidity in raw water sources, where it is significant, should provide insight into water quality management and treatment plant operations.  相似文献   
240.
Suspended sediment data from a 154 ha watershed on northeast Chichagof Island, Alaska, were collected over three fall storm seasons from 1980 to 1982. Sediment rating curves for nine pooled storms explained less than 34 percent of the variation in total suspended solids (TSS). Significantly higher concentrations of suspended sediment occurred during the rising limb of storm hydrographs than for similar flows on the falling limb, accounting for hysteresis loops in TSS versus streamflow plots for individual storms. These hysteresis loops were wider during early season storms, indicating that easily transportable fine sediment may have been flushed from the upper portion of channel banks and from behind large organic debris during early season peak flows. Regression relationships (TSS versus Q) developed for the highest stormflows (> 1 m3/s) had steeper slopes than the lower stormflows (< 1 m3/s). Turbidity correlated well (r=0.94) with TSS for all storm-flow data combined. Organic matter constituted an average of 35 percent (by weight) of TSS for all water quality samples.  相似文献   
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