高效铁系除臭剂净化制药污泥带滤间恶臭的工程应用研究

在实验室条件下考察了自制高效铁系除臭剂的吸附性能,确定出了最佳工艺条件。将该除臭剂应用于制药厂污水处理污泥带滤间的恶臭气体净化,设计了废气处理量为11 000 m³/h的吸附净化系统。工程实际运行效果良好,H₂S去除率可达97％以上。结果表明：该除臭剂对于处理含硫恶臭气体具有良好的实际应用价值,工业应用前景广阔。     

发酵-渗透汽化膜技术制无水乙醇研究进展

渗透汽化膜技术作为一种新型的膜分离技术和清洁生产技术,与发酵法相耦合生产燃料乙醇,具有高效、节能和环保的优势。综述了发酵-渗透汽化膜技术的研究进展,介绍了该工艺动力学模型的研究成果,与传统的发酵法进行了经济性对比,阐述了渗透汽化膜技术应用于无水乙醇工业化生产的现状和存在的问题,展望了发酵-渗透汽化膜技术的研究方向。     

Assessment for Salinized Wasteland Expansion and Land Use Change Using GIS and Remote Sensing in the West Part of Northeast China

Due to human impact under climatic variations, western part of Northeast China has suffered substantial land degradation during past decades. This paper presents an integrated study of expansion process of salinized wasteland in Da’an County, a typical salt-affected area in Northeast China, by using Geographic Information Systems (GIS) and remote sensing. The study explores the temporal and spatial characteristics of salinized wasteland expansion from 1954 to 2004, and land use/cover changes during this period. During the past 50 years, the salinized wasteland in study area have increased by 135,995 ha, and in 2004 covers 32.31% of the total area, in the meantime grassland has decreased by 104,697 ha and in 2004 covers only 13.15% of the study area. Grasslands, croplands and swamplands were found the three main land use types converted into salinized wasteland. Land use/cover changes shows that between 1954 and 2004, 48.6% of grasslands, 42.5% of swamplands, and 14.1% of croplands were transformed into salinized wasteland, respectively. Lastly, the major factors influencing salinized wasteland expansion and land use/cover changes were also explored. In general, climatic factors supplied a potential environment for soil salinization. Human-related factors, such as policy, population, overgrazing, and intensified and unreasonable utilization of land and water resources are the main causes of salinized wasteland expansion.     

Effects of soil properties on heavy metal accumulation in flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) in Pearl River Delta, China

This study was conducted to investigate the effects of soil properties on the heavy metal accumulation in flowering Chinese cabbage (Brassica campestris L. ssp. chinensis var. utilis Tsen et Lee) at the field scale. The concentrations of cadmium (Cd), mercury (Hg), and chromium (Cr) in topsoil and vegetable samples from Nanhai district of Foshan city in the Pearl River Delta (PRD) were analyzed. The results showed that 56.5% of the soil samples exceeded the grade II of the Chinese Soil Environmental Quality Standard (GB 15618-1995) for Hg concentrations, while 8.70% and 17.4% of the vegetable samples exceeded the criteria of the Chinese Safety Qualification of Agricultural Products (GB 18406.1-2001) for Cd and Hg concentrations, respectively. The calculated bio-concentration factor (BCF; i.e., the ratio of the metal concentration in the edible parts of flowering Chinese cabbage to that in soil) values were ranked as: Cd (0.1415) > Cr (0.0061) > Hg (0.0012) (p < 0.01), which demonstrated that Cd was easier to be accumulated in the edible parts of flowering Chinese cabbage than Hg and Cr. Furthermore, the following relationships between (bio-concentration factor) BCF values (BCFs) and soil physicochemical properties were concluded from our results: i) the mean BCFs of coarse-textured soils were higher than those of fine-textured soils; ii) the BCFs decreased with increasing soil pH; iii) the soils with high organic matter(OM) and Cation exchange capacity (CEC) have low BCFs, resulting from their high sorption capacities for Cd, Hg, and Cr. The stepwise linear multiple regression analyses showed that total metal concentrations and available calcium in soils were two main factors controlling the accumulation of Cd, Hg, and Cr in the flowering Chinese cabbage.     

关于农业环境质量评价方法几个问题的探讨

从中国多年农业环境质量与评价工作入手,分析了农业环境质量评价的必要性及特点,探讨了农业环境质量评价的科学程序及与农业环境决策的关系。     

我国乡村城市化进程中的“小城镇病”

本文对我国城镇发展过程中出现的布局分散、土地利用粗放、集聚效应差和环境恶化进行分析,指出布局分散是“小城镇病”的根源之所在;作者认为从规模经济考虑,我国城镇发展方针应调整为：发挥大城市集聚一扩散效应,积极发展中小城市,有重点地选择性发展小城镇。     

湿式双氧水氧化处理染料中间体H-酸钠盐溶液的研究

在0.5 L压力反应器内,对染料中间体H-酸钠盐溶液进行湿式双氧水氧化(WPO)及湿式双氧水催化氧化(CWPO)降解处理.分别考察反应时间、双氧水用量、温度、进水pH值和催化剂等对反应过程与对象污染物降解的影响规律.结果表明,WPO能在温和的条件下降解难于生物降解的有机物,在温度为110℃、压力为0.5 MPa、双氧水用量为理论需用量、进水pH=5的条件下,处理含10 g/L H-酸钠盐的H-酸盐溶液的COD和色度去除率分别为62.0%和98.7%;采用非均相Cu/Ni复合催化剂,在同样操作条件下,CWPO对同一废水的COD和色度去除率分别可达到92.0%和99.9%.表明催化剂的存在大大提高了WPO的氧化效果.     

北京市医疗废物典型可燃组分的物化特性研究

通过对北京市医疗废物典型可燃组分的工业分析、元素分析及热值等物化特性的实验研究,得出了各可燃组分水分含量低、灰分少、挥发分含量高、热值高的结论;在物质组成上,医疗废物典型可燃组分可以分为高碳元素含量物质和低碳元素含量物质两大类.同时,提出了北京市医疗废物处理适宜采用热处理方法,特别是热解处理方法的建议.     

基于电阻率的硫酸污染水泥土检测方法的探讨

电阻率法作为一种简单有效的测试方法,已在岩土工程检测中得到了一定程度的应用.通过室内试验模拟了水泥土试块受不同浓度硫酸溶液污染的反应,采用电阻率法研究了孔隙水电阻率、水泥土电阻率、结构因子与溶液浓度和龄期之间的关系.结果表明,孔隙水和水泥土电阻率随溶液浓度增大而减小、随龄期的增大而增大,结构因子随着溶液浓度和龄期的增加而增加,它们之间具有较高的相关性.这充分说明,电阻率法可应用于硫酸污染水泥土的检测和评价.     

沈阳市辽中县生态环境质量评价

采用中国环境监测总站《生态环境质量评价技术规定》中的生态环境评价指标和计算方法对辽中县生态环境质量进行定量评价。并分析了导致出现制约性因子的因素。