两相UASB反应器处理木薯淀粉废水的启动运行特性研究

采用两段UASB厌氧反应器为主体的工艺处理木薯淀粉废水，在温度为20℃左右，进水为CODcr6000-8000mg／L反应条件下二次启动，经过33d的运行，两段厌氧处理CODcr去除率累计达85％以上，出水CODcr为400-800mg／L。实验结果表明，甲烷段是整个反应器启动的控制阶段，只要控制好各反应器的运行参数，便能很好达到两相分离的目的。     

安钢高炉出铁场除尘工程实践

六号高炉炉前出铁场工程是一项工业污染治理项目，该项目结合安钢实际，利用较少的投资，解决了多年困扰炼铁厂的炉前烟尘污染的问题，该技术结合目前国内中小高炉出铁场综合治理的经验，提出了顶吸加侧吸的综合捕集方式，极大地改善了出铁场的烟尘污染状况，同时回收的粉尘又有极高的利用价值，取得了一定的经济效益。     

Investigation of low-molecular weight organic acids and their spatiotemporal variation characteristics in Hongfeng Lake, China

The identities and concentrations of low-molecular-weight organic acids (LMWOAs) were determined by ion chromatography throughout a 20-m water column in Hongfeng Lake, China. The spatiotemporal variations of LMWOAs and their contributions to dissolved organic matter (DOM) in a research period of 24 hr were also investigated. The results demonstrated that five LMWOAs (lactic, acetic, pyruvic, sorbic, oxalic acid) were detected, and their total concentration and proportion in DOC were 6.55 μmol/L and 7.47%. Their average levels were 2.50, 0.65, 2.35, 0.96 and 0.09 μmol/L, respectively. LMWOAs were higher during daytime (10:00-18:00 on Jun 13, 2008) than nighttime (21:00-6:00 the next morning), in particular 4.99 μmol/L high in the epilimnion ( 1 m water depth), reflecting the fact that direct import from terrigenous sources and photochemical production from humic materials were dominant during LMWOAs’ origin and accumulation. The same factors caused LMWOAs to be 0.63 μmol/L in the epilimnion higher than in the hypolimnion. The rapid decrease of total organic acid (TOA) up until 18:00 mainly resulted from bio-uptake and mineralization in the hypolimnion (>1 m water depth). Pyruvic acid increased with time in the epilimnion and decreased in the hypolimnion, largely related to the two contrary processes of continuous degradation and synthesis of macromolecular organic matter during life materials’ cycle mediated by organisms. Simultaneously, plankton behavior and thermal stratification played a pivotal role in LMWOAs’ behavior in the water column, causing decreasing and increasing profiles. The distribution of LMWOAs represents an interesting resource for biogeochemical research of DOM in aquatic ecosystems.     

Study of the pyrolysis of ionic liquid [Bmim]Cl-pretreated mango pit at low temperature

Journal of Material Cycles and Waste Management - In the present work, mango pit was used to study the feasibility of converting ionic liquid-pretreated biomass into biofuel and activated biochar...     

煤气脱硫废料综合利用新工艺

针对煤气脱硫废料（简称废料）的成分（硫、碳、萘及少量其他有机物）,提出了一种处理废料的新工艺,先用乙酸乙酯提取废料中的萘和少量其他有机物,再用复合溶剂B加热溶解废料,热过滤得碳粉,最后将溶液冷却结晶分离出硫。实验结果表明：在乙酸乙酯与废料的质量比（R1）为3.75,提取温度为60℃,提取时间为4h的条件下,萘回收率为98%,纯度大于等于70%,在复合溶剂B与提取剩余物的质量比（R2）为2.69,过滤温度为100℃的条件下,硫回收率接近100%,纯度大于等于99%,碳回收率和纯度为100%。     

土壤有机物污染控制标准制订的方法学研究

指出了中国现行土壤环境质量标准存在的问题.对日本和美国等发达国家的有机物污染土壤质量控制标准进行了分析.从土壤环境质量基准制订的方法学和污染控制标准的确定原则上,提出了制订中国土壤有机物污染控制标准的建议.     

正压空气呼吸器呼气阀弹簧设计

通过对开启压力与呼气阀及正压空气呼吸器相关指标之间关系的分析,提出将开启压力作为呼气阀设计参数可实现呼气阀的定量设计,并在此基础上对正压空气呼吸器呼气阀弹簧进行了定量设计和验证,同时对影响呼气阀弹簧设计的相关因素进行了详细探讨.     

正压空气呼吸器面罩的数字化设计

本文介绍了一种新型正压空气呼吸器面罩的结构设计。分别从数据采集、曲面重构及实体建模等方面对面罩的数字化设计步骤进行了详细阐述,并对面罩视野进行了初步校核。     

Characteristics of phosphorus components in surface sediments from a Chinese shallow eutrophic lake (Lake Taihu): new insights from chemical extraction and <Superscript>31</Superscript>P NMR spectroscopy

As a primary factor responsible for lake eutrophication, a deeper understanding of the phosphorus (P) composition and its turnover in sediment is urgently needed. In this study, P species in surface sediments from a Chinese large eutrophic lake (Lake Taihu) were characterized by traditional fractionation and ³¹P nuclear magnetic resonance (NMR) spectroscopy, and their contributions to the overlying water were also discussed. Fractionation results show that NaOH-P predominated in the algal-dominated zone, accounting for 60.1% to total P in Zhushan Bay. Whereas, refractory fractions including HCl-P and residual-P were the main P burial phases in the macrophyte-dominated zone, the center and lakeshore. Recovery rates of the total P and organic P were greatly improved by using a modified single-step extraction of NaOH-EDTA, ranging from 22.6 to 66.1% and from 15.0 to 54.0%. Ortho-P, monoester-P, and pyro-P are identified as the major P components in the NaOH-EDTA extracts by ³¹P NMR analysis. Trace amount of DNA-P appeared only in sediments from algal- and macrophyte-dominated zones, ascribing to its biological origin. The relative content of ortho-P is the highest in the algal-dominated zone, while the biogenic P including ester-P and pyro-P is the highest in the macrophyte-dominated zone. Moreover, ortho-P and pyro-P correlated positively with TP and chlorophyll a in the overlying water, whereas only significant relationships were found between monoester-P, biogenic P, and chlorophyll a. These discrepancies imply that inorganic P, mainly ortho-P, plays a vital role in sustaining the trophic level of water body and algal bloom, while biogenic P makes a minor contribution to phytoplankton growth. This conclusion was supported by the results of high proportion of biogenic P in algae, aquatic macrophytes, and suspended particulate from the published literature. This study has significant implication for better understanding of the biogeochemical cycling of endogenous P and its role in affecting lake eutrophication.     

聚环氧琥珀酸萃取锰泥残渣中铬的研究

聚环氧琥珀酸(PESA)是一种具有无磷及非氮结构、环境友好型水溶性聚合物,且具有螯合多价金属阳离子的性能和可生物降解性的特征,选取其作为锰泥残渣中铬的螯合萃取剂,研究了不同pH、螯合萃取剂剂量、搅拌时间下PESA对铬的萃取率。结果表明:(1)最佳萃取条件为pH=4、PESA剂量30mg/g、搅拌时间60min;在最佳萃取条件下,铬的萃取率可达95%。(2)从结构上看,PESA是由醚基和羧基基团组成的高分子聚合物,羧基基团是与金属离子作用的主要官能团,它对Ca2+、Mg2+、Zn2+、Cr(Ⅲ)、Cr(Ⅵ)和Pb2+等有较强的螯合能力;从溶液的配位角度看,PESA与金属有较强的结合能力。因此,PESA对锰泥残渣中的铬有萃取作用。