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微波协同氧化预处理垃圾渗滤液NF膜滤浓缩液研究 总被引:1,自引:0,他引:1
针对城市生活垃圾填埋场垃圾渗滤液NF膜处理后产生的浓缩液处理难问题,采用微波协同氧化技术对其进行预处理,探讨了pH值、预反应时间、药剂用量、微波反应时间等因素对浓缩液CODcr及色度去除率的影响.结果表明:当pH=4,预反应时间60 min,药剂用量1g/l、微波反应时间3 min时,CODcr、色度的去除率分别为71.2%,80%.预处理后的出水CODcr及色度指标达到垃圾渗滤液现有生化处理系统的进水要求. 相似文献
965.
Juan Zhao Zhe Wang Ting Wu Xinming Wang Wanhong Dai Yujie Zhang Ran Wang Yonggan Zhang Chengfei Shi 《环境科学学报(英文版)》2016,28(7):257-269
A laboratory study was conducted to investigate volatile organic compound(VOC) emissions from agricultural soil amended with wheat straw and their associations with bacterial communities for a period of 66 days under non-flooded and flooded conditions. The results indicated that ethene, propene, ethanol, i-propanol, 2-butanol, acetaldehyde, acetone,2-butanone, 2-pentanone and acetophenone were the 10 most abundant VOCs, making up over 90% of the total VOCs released under the two water conditions. The mean emission of total VOCs from the amended soils under the non-flooded condition(5924 ng C/(kg·hr)) was significantly higher than that under the flooded condition(2211 ng C/(kg·hr)). One "peak emission window" appeared at days 0–44 or 4–44, and over 95% of the VOC emissions occurred during the first month under the two water conditions. Bacterial community analysis using denaturing gradient gel electrophoresis(DGGE) showed that a relative increase of Actinobacteria, Bacteroidetes, Firmicutes and γ-Proteobacteria but a relative decrease of Acidobacteria with time were observed after straw amendments under the two water conditions. Cluster analysis revealed that the soil bacterial communities changed greatly with incubation time, which was in line with the variation of the VOC emissions over the experimental period. Most of the above top 10 VOCs correlated positively with the predominant bacterial species of Bacteroidetes, Firmicutes and Verrucomicrobia but correlated negatively with the dominant bacterial species of Actinobacteria under the two water conditions. These results suggested that bacterial communities might play an important role in VOC emissions from straw-amended agricultural soils. 相似文献
966.
Tianlong Zheng Qunhui Wang Zhining Shi Yue Fang Shanshan Shi Juan Wang Chuanfu Wu 《环境科学学报(英文版)》2016,28(12):21-31
A three-dimensional electrochemical oxidation(3D-EC) reactor with introduction of activated carbon(AC) as particle micro-electrodes was applied for the advanced treatment of secondary wastewater effluent of a wet-spun acrylic fiber manufacturing plant. Under the optimized conditions(current density of 500 A/m~2, circulation rate of 5 mL/min, AC dosage of 50 g, and chloride concentration of 1.0 g/L), the average removal efficiencies of chemical oxygen demand(COD_(cr)), NH3–N, total organic carbon(TOC), and ultraviolet absorption at 254 nm(UV_(254)) of the 3D-EC reactor were 64.5%, 60.8%, 46.4%, and 64.8%, respectively; while the corresponding effluent concentrations of COD_(cr), NH_3–N, TOC, and UV_(254) were 76.6, 20.1, and42.5 mg/L, and 0.08 Abs/cm, respectively. The effluent concentration of COD_(cr) was less than 100 mg/L, which showed that the treated wastewater satisfied the demand of the integrated wastewater discharge standard(GB 8978-1996). The 3D-EC process remarkably improved the treatment efficiencies with synergistic effects for COD_(cr), NH_3–N, TOC, and UV_(254) during the stable stage of 44.5%, 38.8%, 27.2%, and 10.9%, respectively, as compared with the sum of the efficiencies of a two-dimensional electrochemical oxidation(2D-EC) reactor and an AC adsorption process, which was ascribed to the numerous micro-electrodes of AC in the 3D-EC reactor. Gas chromatography mass spectrometry(GC–MS) analysis revealed that electrochemical treatment did not generate more toxic organics, and it was proved that the increase in acute biotoxicity was caused primarily by the production of free chlorine. 相似文献
967.
山东省汽车喷涂行业VOCs排放特征研究 总被引:3,自引:1,他引:2
采用气袋采样-气相色谱/质谱法,采集并分析了山东省内小型通用车、货车、电动商务车以及半挂车4类典型汽车喷涂企业挥发性有机物(VOCs)的排放特征。结果表明:山东省汽车喷涂企业中VOCs排放总量以及检出数量排序为:半挂车喷涂企业电动商务车喷涂企业货车喷涂企业小型通用车喷涂企业。各类汽车喷涂企业喷漆以及烘干车间排放的VOCs大多以苯类物质为主(小型通用车面漆烘干车间除外),在小型通用车以及半挂车涂装企业废气中烷烃类物质占比较大。不同企业以及各企业不同工序之间特征VOCs排放浓度有较大差别,喷漆车间特征VOCs浓度要远高于烘干车间。 相似文献
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970.
为揭示南海北部表层海水中参与卡尔文循环的固碳基因多样性及其与环境因子的关系,本研究以卡尔文循环中的关键酶核酮糖-1,5-二磷酸羧化酶/加氧酶(Rubis CO)的Ⅰ、Ⅱ型基因(cbbL、cbbM)作为分子标记,采用Illumina Miseq高通量测序技术对海水中的固碳基因多样性进行分析,并结合多元统计分析的方法,探讨了固碳基因多样性与环境因子的关系.结果显示,在南海北部表层海水中,含cbbL基因固碳基因主要归属于变形菌门(Proteobacteria)、蓝藻门(Cyanobacteria)和厚壁菌门(Firmicutes),其中,优势亚群分别是γ-变形菌亚门(45.3%)、蓝细菌(30.9%)和β-变形杆菌亚门(23.8%);而含cbbM基因的固碳菌群未检测到;近岸的A9站位与其他站位物种组成有一定的差异,异着色菌属(Allochromatium)、硫杆菌属(Thiobacillus)和硫单胞菌属(Thiohalomonas)为其特有菌属.相关性和冗余分析(RDA)结果显示,含cbbL基因的固碳基因丰度与水温、盐度呈显著负相关(p0.01),与硝酸盐、亚硝酸盐、硅酸盐呈显著正相关(p0.01). 相似文献