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1.
刘名扬 《四川环境》1993,12(2):29-35
本文研究了“金刚石合成棒含镍酸洗废水的处理”,采用硫化沉淀法,因金属硫化物的溶度积小于金属氢氧化物的溶度积,使镍沉淀完全彻底,不可能出现返溶现象,水质达到国家排放标准。并讨论了含镍废水处理的PH值、硫化钠浓度、搅拌时间、沉降速度与镍沉淀率的关系和影响。得出了处理金刚石合成棒含镍酸洗废水的基本原理,获得了最佳的工艺技术条件,为工业化处理含镍废水提供了重要的依据。  相似文献   

2.
苏联解体和东欧剧变后 ,因其核能使用不当而造成的大量核污染问题浮出了水面。切尔诺贝利事件只是其中最受人关注的事件之一。现在有 13个类似切尔诺贝利型的核反应堆仍在运行着。包括前苏联科学家在内的大多数专家们都认为这些反应堆存在着隐患。苏联解体后 ,其三个核燃料、核武器的制造及核燃料再处理的地点被曝光 ,它们是切尼亚宾茨克、托马茨克和克拉斯诺雅茨克。同时 ,这些地点制造了核废物。切尼亚宾茨克的核废料被倒进了得卡河和卡来采湖 ,其他核废物也被秘密倒进了大海或者草草填埋了事。据估计仅莫斯科周围的秘密核废物处置场就有 …  相似文献   

3.
秸秆生物反应堆技术是一项新型农业栽培技术。本文对黄瓜温室应用秸秆生物反应堆技术的对比试验情况进行了介绍,并就农产品品质、产量、上市时间、植物生长等情况进行了分析。  相似文献   

4.
企业拆除施工活动直接影响周边环境和居民生活,因此施工方要重视其在施工过程中的环境污染情况,针对粉尘、噪音、废水进行有效的防治。以天津市某中药生产公司拆除为例,探讨有关企业拆除活动的环境污染防治措施,为企业拆除施工活动提供参考。  相似文献   

5.
《环境教育》2014,(8):36-37
8月8日,从山西省太原市环保局召开的新闻发布会上获悉,10月底前,涉及火电机组、造纸、重金属及混凝土搅拌4个行业的30家污染企业将全部关停。企业务必于10月31日前,按“停止生产,拆除主要生产设施”的标准全部关停到位。  相似文献   

6.
城市固体废物生物处理方法及其可行性   总被引:7,自引:2,他引:7  
生物反应堆是通过强化微生物转化和降解有机废物的能力进行处理固体废物的一种方法。本文分别对好氧生物处理、厌氧生物处理和兼性生物处理的机理、影响因素以及各污染物质的迁移转化规律进行综合分析。研究表明生物反应堆具有明显的社会、环境、经济效益,是实现可持续发展的一条重要途径,为以后的研究和应用提供可靠的理论依据。  相似文献   

7.
本文给出了计算核设施周围环境居民剂量的方法。估算了1000瓩铀氢锆反应堆正常运行和事故工况对周围环境居民造成的剂量负担。估算表明,反应堆运行对广大居民健康没有影响,对环境是安全的。  相似文献   

8.
本文通过对SF_6开断气体的毒性试验和对110kVSF_6全封闭组合电器设备的解体,对SF_6电弧分解物的毒性及设备解体时的防护问题提出看法。  相似文献   

9.
简要论述了秸秆生物反应堆技术原理、技术效应及在天津市设施农业中示范应用效果,并提出了加快秸秆生物反应堆技术应用推广的对策及建议。  相似文献   

10.
为解决海上钻井油基岩屑上岸后热解脱油残渣堆积及潜在环境风险问题,研究了残渣与偏高岭土混掺制备混凝土的可行性。考察了残渣基本性能及不同掺量、养护龄期下混凝土力学性能与耐久性能变化情况,并探究了混凝土强度形成机理及环境特性。结果表明:单掺残渣对混凝土性能具有较大的负效应,在最佳掺量10%时可达到设计强度(30MPa)。偏高岭土可有效改善混凝土性能,提升残渣掺量。混凝土主要矿物相为二氧化硅、钙钒石、氢氧化钙和水化硅酸钙等,这些水化产物在体系内共同作用赋予混凝土基本强度。混凝土浸出液COD、重金属离子等指标可达到GB8978—1996《污水综合排放标准》一级排放限值,环境安全性良好。该研究为海上油气田油基岩屑回收上岸后热解残渣的资源化处置提供参考。  相似文献   

11.
针对常规储罐检测工作量大、效率低的问题,利用三维激光扫描仪对某储罐进行外部检测,获取高精度的储罐三维点云数据,通过建模形成一个拟合罐体,与理想罐体进行3D比较得到储罐变形的整体情况,该方法能够对储罐的变形评估做出准确判断,距离储罐底板0.3 m处有最大径向偏差51.63 mm,0.9 m处有最大倾斜度0.177°,基于三维激光扫描技术为储罐罐壁变形检测提供了一种可靠的新方法。  相似文献   

12.
The process of producing cement products from solid waste can increase the level of pollutants in the cement products. Therefore, it is very important to establish a pollution control standard for cement products to protect the environment and human health. This paper presents acceptance limits for the availability of heavy metals in cement products which have been produced from solid wastes and explains how the limits have been calculated. The approach and method used to formulate these criteria were based on EN 12920. The typical exposure scenarios used in this paper involve concrete being used for drinking water supply pipelines and concrete pavements and are based on an analysis of typical applications of cement in China, and the potential for contact with water. The parameters of a tank test which was based on NEN 7375 were set in accordance with the environmental conditions of typical scenarios in China. Mechanisms controlling the release of heavy metals in concrete and a model for that release were obtained using the leaching test. Finally, based on acceptance criteria for drinking water and groundwater quality in China, limit values for the availability of heavy metals in concrete were calculated.  相似文献   

13.
This study identified the levels and sources of heavy metal contamination in road dust from busy traffic areas in a typical industrial city in Korea. This study compared the total concentrations, as determined by aqua regia digestions and atomic absorption spectroscopy, of cadmium (Cd), copper (Cu), lead (Pb), zinc (Zn) and nickel (Ni) in the road dust from areas with different characteristics such as traffic rotaries, downtown areas, circulation roads, and asphalt and concrete highways. The contamination levels of the heavy metals in the road dust were evaluated using the contamination factor and the degree of contamination. The contamination levels of the heavy metals in the road dust were highly dependent on traffic volume and atmospheric dispersion from traffic rotaries. Industrial emissions and the frequency of brake use and vehicles coming to a complete stop were additional factors that affected the contamination levels in downtown areas. The concrete highway had higher contamination levels of the heavy metals than the asphalt highway. Vehicle speed was also a strong contributing factor to the degree of contamination of heavy metals in the road dust from the circulation roads and highways.  相似文献   

14.
《Resources Policy》2002,28(1-2):39-47
Material flows of concrete from construction and demolition (C&D) waste in Taiwan have grown considerably over the last two decades, Hsiao et al. (2001). This increased flow puts pressure on limited national disposal capacity and has indirectly caused ecological damage to domestic riparian zones used as sources of natural aggregate. Using existing statistics and literature sources for C&D waste generation in Taiwan we have developed a dynamic model of domestic material flows of concrete waste and employ statistical analyses to obtain projections of future material flows. Our major findings are: (1) Taiwan’s rate of waste concrete generation in 2001 for the residential and commercial construction industry was approximately 2.4 Million Metric Tons (MMT) per year, averaging 0.11 metric tons of waste concrete generated annually by each Taiwanese; (2) Around the year 2009, the national rate will more than triple to exceed the spike in C&D concrete waste generation that occurred after the Chi Chi earthquake 9/21/99, 8.5 MMT. (3) Aside from pilot-scale development of waste concrete utilization technology, nationwide recycling rates remain negligible. Without resource recovery, the volume of C&D waste generation by 2009 is projected to occupy nearly 7% of all existing and planned domestic landfill capacity. A target is established to raise resource recovery rates for waste concrete to 50% by 2005 and a 100% nationwide recycling rate by 2009.  相似文献   

15.
In Tanzania, construction and demolition (C&D) waste is not recycled and knowledge on how it can be recycled especially into valuable products like building materials are still limited. This study aimed at investigating the possibility of recycling the C&D waste (mainly cementitious rubble) into building material in Tanzania. The building materials produced from C&D waste was concrete blocks. The concrete blocks were required to have a load bearing capacity that meets the building material standards and specifications. Eight C&D waste samples were collected from C&D building sites, transported to the recycling site, crushed, and screened (sieved) to get the required recycled aggregates. Natural aggregates were also used as control. The recycled aggregates were tested in the laboratory following the standard methods as specified in Tanzanian standards. The physical, mechanical and chemical characteristics were determined. The physical and mechanical results showed that recycled aggregates were weaker than natural aggregates. However, chemically they were close to natural aggregates and therefore suitable for use in new concrete block production. In the production process, each experiment utilized 100% recycled aggregates for both fine and coarse portions to replace natural aggregates. The Fuller's maximum density theory was used to determine the mix proportions of materials in which a method that specifies concrete mix by system of proportion or ratio was used. The concrete blocks production processes included batching, mixing (that was done manually to get homogeneous material), compacting and moulding by hand machine and curing in water. After 28 days of curing, the concrete blocks were tested in the laboratory on compressive strength, water absorption ratio and density. The results showed that the blocks produced with 100% recycled aggregates were weaker than those with natural aggregates. However, the results also showed that there is a possibility of recycling the C&D waste into building material because 85% of the tested concrete block specimens from recycled aggregates achieved a compressive strength of 7 N/mm2, which is defined as the minimum required load bearing capacity in Tanzania. Therefore, the C&D waste could be a potential resource for building material production for sustainable construction in Tanzania rather than discarding it. Further work should focus on the economic feasibility of production of concrete blocks with recycled aggregates in Tanzania.  相似文献   

16.
To avoid eutrophication of receiving waters, effective methods to remove P in urban and agricultural runoff are needed. Crushed concrete may be an effective filter material to remove dissolved and particulate P. Five types of crushed concrete were tested in the laboratory to evaluate the retention capacity of dissolved P. All types removed P very effectively (5.1-19.6 g P kg(-1) concrete), while the possible release of bound P varied between 0.4 and 4.6%. The retention rate was positively related to a decreasing concrete grain size due to an increasing surface area for binding. The P retention was also related to a marked increase in pH (up to pH 12), and the highest retention was observed when pH was high. Under these circumstances, column experiments showed outlet P concentrations <0.0075 mg P L(-1). Furthermore, experiments revealed that release of heavy metals is of no importance for the treated water. We demonstrate that crushed concrete can be an effective tool to remove P in urban and agricultural runoff as filter material in sedimentation/infiltration ponds provided that pH in the treated water is neutralized or the water is diluted before outlet to avoid undesired effects caused by the high pH.  相似文献   

17.
重质燃料油中主要芳烃在自然条件下的风化规律   总被引:4,自引:0,他引:4  
文章在自然环境条件下对重质燃料油进行了风化模拟实验,采用气质(GC/MS)联用仪分析了重质燃料油中主要芳烃组分及其变化。结果表明:该重质燃料油中主要芳烃为苯类(C_nB)、萘(C_nN)类、菲(C_nP)类、二苯并噻吩(C_nD)类;在自然条件下,经过1周的风化,C_nB和C_0N完全损失;经过6周风化,C_1N完全损失;经过12周的风化,C_2N完全损失,3环的PAHs无明显变化。同时指出C_2D/C_2P和C_3D/C_3P的比值以及烷基化二苯并噻吩的同分异构体分布可用于区别其它油品,并且风化后变化不大,仍可较好地用于油品的鉴定。  相似文献   

18.
刘宝剑  蓝俊康 《四川环境》2007,26(4):93-96,101
土聚物是一种新型的无机聚合物,它具有类沸石似的网络结构,其分子链由Si、0、Al等以共价键连接而成。由于它的渗滤性低,对重金属元素不仅予以物理束缚也能进行化学束缚,因此利用它来固化重金属污染物的效果很好。同时,土聚物的强度又比由硅酸盐水泥制成的混凝土要高许多,因此其固化物还可被应用于道路或其他建设领域。但遗憾的是目前利用含重金属污泥制成土聚水泥的研究还基本属于空白阶段,建议加强这方面的研究。  相似文献   

19.
王绪旺  蒋应军 《四川环境》2021,40(1):169-173
为分析铁尾矿路用对道路沿线土壤环境质量影响的程度,对铁尾矿化学成分及有害物质进行测定,以秦巴山区的山地黄棕壤作为道路建设的耕土环境,把铁尾矿按70%~90%的推荐比例掺入,铁尾矿中的重金属按照最不利的全浸入式扩散进行分析,对黄棕壤中重金属含量超过限制要求的重金属进行安全修复,使铁尾矿道路沿线黄棕壤的重金属含量满足限制要...  相似文献   

20.
随着生活垃圾焚烧处理方式的不断推广,焚烧飞灰的产生量也不断增加。按照我国固体废物分类方法,焚烧飞灰属于危险废物,必须进一步处置才能进入填埋场或资源化利用。本文分析了飞灰物理化学特性,论述了常规处置技术(水泥固化、化学药剂稳定化、酸溶剂提取和熔融固化等)存在的问题。将原始飞灰直接应用于水泥、混凝土或路基材料,飞灰中高含量的重金属和盐类会产生新的环境问题。飞灰水洗可以高效去除其中的可溶性盐类,水洗飞灰在焙烧后重金属的浸出浓度远低于原始飞灰烧结后的相应浓度,飞灰水洗-焙烧技术具有很好的应用前景。  相似文献   

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