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1.
《化工环保》2008,28(2)
该发明公开了一种综合利用黄磷熔渣和尾气生产微晶玻璃的方法。其方法为:将温度为1450~1500℃的黄磷熔融炉渣加入熔融炉中,同时进行炉前快速分析,使物料组分(质量分数)符合SiO2 50%~60%、A12036%~7%、CaO 22%~30%、  相似文献   

2.
以铅锌尾矿和CRT玻璃固体废弃物为主要原料,采用烧结法制备微晶玻璃材料.为确定基础玻璃的成分,以及尾矿、CRT玻璃及各化工原料的用料比例,设计了正交实验;研究了CaO,Al2O3,MgO等氧化物添加量对微晶玻璃结构及性能的影响规律.通过差热分析(DTA)、X射线衍射(XRD)、扫描电镜(SEM)等分析方法,考察了微晶玻璃产品的晶相、晶体形貌特征及性能.结果表明:利用铅锌尾矿、CRT玻璃废弃物制备微晶玻璃的最佳配方为:尾矿20%、CRT玻璃30%、添加辅料石英砂29.7%、方解石25%、Al2O3 12%、晶核剂TiO2 1%.SEM和XRD分析可知,微晶玻璃的主晶相为透辉石;打磨抛光处理后,平均显微硬度为8.76 GPa,平均抗折强度为223.1MPa;经酸、碱浸蚀后,质量变化分别为0.43%和0.58%,耐酸碱腐蚀性良好.  相似文献   

3.
李雪馨  刘益 《化工环保》1994,14(3):178-179
黄磷生产三废的综合利用我厂以黄磷为龙头产品,采用电炉法每生产1t黄磷,排出废气2700-3000万m ̄3(含CO约90%)、废渣8-10t(主要成份为硅酸钙),在废水的处理过程中还会排出大量的磷泥。这些废物如直接排放,既污染环境又浪费了资源。我厂科技...  相似文献   

4.
金燕燕 《化工环保》1991,11(2):120-122
1.概述黄磷渣是电炉法生产黄磷过程中排放的固体废弃物。过去小部分销售给水泥厂作水泥掺合剂生产硅酸盐水泥,大部分用作建筑材料,其利用价值不高。1988年,南化公司在中国科学院南京土壤研究所协助下,利用黄磷渣生产硅钙肥,并在江苏省江宁县、溧阳县等地的水稻田进行肥效试验,结果表明:施用硅钙肥,水稻生长早发,分蘖快而稳,叶面积增加,茎杆粗壮,并能提高光合作用和抗病能力,还可提早抽穗,成熟期提  相似文献   

5.
在黄磷生产过程中,每生产1吨黄磷,约产生0.5吨磷泥。这些磷泥的处理,一直是我国黄磷生产中的一大难题。本文介绍国内外处理磷泥的主要方法,以供参考。  相似文献   

6.
废水中黄磷在常温下的转化速率1前言黄磷是一种剧毒物,一旦进入水体将给水生生物带来危害,所以大部分黄磷生产厂都采取废水闭路循环的办法,避免黄磷废水排入江河。黄磷在水中溶解度极小,仅为3.3mg/L,它在水中或空气中化学性质活泼,易发生歧化和氧化反应,但...  相似文献   

7.
黄磷尾气现场脱硫试验   总被引:1,自引:0,他引:1  
黄磷尾气的主要成分是CO,其中含硫杂质主要以硫化氢的形式存在。测定了黄磷尾气中硫化氢、氧气的含量,分别采用吸收、吸附工艺及其组合工艺对黄磷尾气进行了现场脱硫试验,得出了最佳的黄磷尾气净化脱硫工艺,即吸收、活性炭变温吸附。出口气中H2s的质量浓度为1—5mg/m^3,净化效率达到99.7%。  相似文献   

8.
专利资讯     
用废旧循环回收玻璃粉末作为填充物的乙烯基聚合粘合物;废显像管碎玻璃专用清洗设备;废显像管碎玻璃清洗剂及其制备方法;利用废碎啤酒瓶生产无气孔微晶玻璃板材的原料配方及其制备方法;用废玻璃制作的微晶玻璃板;利用废旧荧光灯管制备泡沫玻璃的方法。  相似文献   

9.
重点介绍了炉渣中的铝铬渣、铬铁渣、钒铁渣制备耐火材料工艺技术及应用,其广泛用于有色冶金炉窑的工作衬,使用效果好。同时分别介绍了利用钛铁渣、硼铁渣、高炉渣、钢渣、富硼渣、铝渣、铝灰、黄磷渣、气化炉渣、石化工业催化剂渣生产耐火材料。炉渣数量大,种类多,深入研究,以期使更多炉渣用做耐火材料。  相似文献   

10.
《化工环保》2008,28(2)
该发明公开了一种采用电炉法生产黄磷的工艺和装置,特别涉及电炉法生产黄磷排放物综合利用的工艺和装置。电炉法生产黄磷产生的尾气通过黄磷尾气净化装置净化,并在蓄热换热器内燃烧将热量传递给换热介质,换热后的热介质送至经过改进后的循环流化床锅炉装置烟气喷嘴进入循环流化床锅炉燃烧室,  相似文献   

11.
Concentrations and total quantity of cadmium (Cd), cupper (Cu),lead (Pb) and zink (Zn) were determined in biomass and soil compartments in a replicated tree species experiment with 27-yr-old stands growing on former farmland in N.E. Sweden. Sequentialextractions of soil samples were performed in order to estimate the exchangeable and an organically bound fraction of each element. The tree species included were Picea abies (L.)H. Karst., Pinus sylvestris L., Pinus contorta Dougl., Larix sibirica Ledeb., and Betula pendula Roth.Tree species influenced the rate of removal of Cu, Pb and Zn incase of stemwood harvesting, and of Cd, Cu and Zn in the case ofwhole-tree harvesting. B. pendula and P. abies had higher quantities and average concentrations of Zn in the biomass. For all species, >50% of the Zn in the stems was found in the bark. P. abies and L. sibirica had higher quantities of Cu in the biomass than the other species.P. abies and P. contorta had high quantities of Cd inthe biomass in relation to the other species. Branches and stembark contained high concentrations of Cd and Pb in relation to foliage and stemwood. Dead branches had especially high concentrations of Pb. The high accumulation rate of Zn in thebiomass of B. pendula was related to a low exchangeable amount of Zn in the A horizon. In the superficial centimeters ofthe A horizon, a depletion similar to that found for Zn was detected for Cu, whereas for Cd and Pb, no correlations were found between quantities of elements in the trees and element pools in the soil.  相似文献   

12.
Recent starch-plastic research at the National Center for Agricultural Utilization Research is reviewed and related worldwide efforts are noted. Properties of starch that influence its formulation and performance in plastics are discussed. Methods are given for preparation of starch-poly(methyl acrylate) graft copolymer, starch-poly(ethylene-co-acrylic acid), and starch-poly(ethylene-co-acrylic acid)-polyethylene plastics. Their physical properties are discussed, as is degradability by enzymes or amylolytic organisms from soil, ponds, and streams.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.  相似文献   

13.
Bioassessment is a useful tool to determine the impact of logging practices on the biological integrity of streams and wetlands. Measuring biota directly has an intuitive appeal for impact assessment, and biota can be superior indicators to physical or chemical characteristics because they can reflect cumulative impacts over time. Logging can affect stream and wetland biota by increasing sedimentation rates, altering hydrologic, thermal, and chemical regimes, and changing the base of food webs. Biotic impacts of logging on streams compared to wetlands probably differ, and in this paper we review some of those differences. In streams, invertebrates, fishes, amphibians, algae, and macrophytes have been used as indicators of logging impacts. In wetlands, bioassessment is just beginning to be used, and plants and birds are the most promising indicator taxa. Various best management practices (BMPs) have been developed to reduce the impacts of logging on stream and wetland biota, and we review quantitative studies that have evaluated the efficacy of some of these techniques in streams and wetlands in the eastern United States. Remarkably few studies that address the overall efficacy of BMPs in limiting biotic changes in streams and wetlands after BMP implementation have been published in scientific journals, although some work exists in reports or is unpublished. We review these works, and compile conclusions about BMP efficacy for biota from this body of research.  相似文献   

14.
Air emissions and residual ash samples were collected and analyzed during experiments of open, uncontrolled combustion of electronic waste (e-waste), simulating practices associated with rudimentary e-waste recycling operations. Circuit boards and insulated wires were handled separately to simulate processes associated with metal recovery. The average emissions of polychlorinated dibenzodioxins and dibenzofurans (PCDD/PCDFs) were 92 ng toxic equivalency (TEQ)/kg [n = 2, relative standard deviation (RSD) = 98%] and 11 900 ng TEQ/kg (n = 3, RSD = 50%) of the initial mass of the circuit boards and insulated wire, respectively. The value for the insulated wire is about 100 times higher than that for backyard barrel burning of domestic waste. The emission concentrations of polybrominated dibenzodioxins and dibenzofurans (PBDD/PBDFs) from the combustion of circuit boards were 100 times higher than for their polychlorinated counterparts. Particulate matter (PM) sampling of the fly ash emissions indicated PM emission factors of approximately 15 and 17 g/kg of the initial mass for the circuit boards and insulated wire, respectively. Fly ash samples from both types of e-waste contained considerable amounts of several metallic elements and halogens; lead concentrations were more than 200 times the United States regulatory limits for municipal waste combustors and 20 times those for secondary lead smelters. Leaching tests of the residual bottom ash showed that lead concentrations exceeded U.S. Environmental Protection Agency landfill limits, designating this ash as a hazardous waste.  相似文献   

15.
Chemical weathering losses were calculated for two conifer stands in relation to ongoing studies on liming effects and ash amendments on chemical status, soil solution chemistry and soil genesis. Weathering losses were based on elemental depletion trends in soil profiles since deglaciation and exposure to the weathering environment. Gradients in total geochemical composition were assumed to reflect alteration over time. Study sites were Horröd and Hasslöv in southern Sweden. Both Horröd and Hasslöv sites are located on sandy loamy Weichselian till at an altitude of 85 and 190 m a.s.l., respectively. Aliquots from volume determined samples from a number of soil levels were fused with lithium metaborate, dissolved in HNO3, and analysed by ICP – AES. Results indicated highest cumulative weathering losses at Hasslöv. The weathering losses for the elements are in the following order:Si > Al > K > Na > Ca > MgTotal annual losses for Ca+Mg+K+Na, expressed in mmolc m-2 yr-1, amounted to c. 28 and 58 at Horröd and Hasslöv, respectively. Variations between study sites could not be explained by differences in bulk density, geochemistry or mineralogy. The accumulated weathering losses since deglaciation were larger in the uppermost 15 cm than in deeper B horizons for most elements studied.  相似文献   

16.
Much work has been done on gaseous emissions and leaching of nitrogenous compounds from whole soil profiles and also from soil surface measurements which are assumed to be mainly due to topsoil activity. In soils with an impervious clay subsoil, the boundary between the topsoil and subsoil may provide an interface for microbial activity, including N transformations. In this study, we investigated movement and transformations of two reactive N species (nitrate and urea) at the subsoil interface using a series of replicate, intact soil blocks, under two contrasting watering regimes. We measured fluxes in both liquid and gaseous phases and demonstrated that nitrate reaching the subsoil interface does not necessarily leach into water systems, but may denitrify immediately and could, therefore, add to atmospheric pollution through N2O production. On the other hand, ammonium reaching the subsoil interface either directly, or after mineralization, appears to be more mobile than expected and has the potential to pollute watercourses.  相似文献   

17.
We have studied particulate matter (PM) concentrations,PM10 and PM2.5, measured in an urban air qualitymonitoring network in the Helsinki Metropolitan Area during1997–1999. The data includes PM10 concentrationsmeasured at five locations (two urban traffic, one suburbantraffic, one urban background and one regional backgroundsite) and PM2.5 concentrations measured at twolocations (urban traffic and urban background sites). Theconcentrations of PM10 show a clear diurnal variation,as well as a spatial variation within the area. Bycontrast, both the spatial and temporal variation of thePM2.5 concentrations was moderate. We have analysedthe evolution of urban PM concentrations in terms of therelevant meteorological parameters in the course of oneselected peak pollution episode during 21–31 March, 1998.The meteorological variables considered included wind speedand direction, ambient temperature, precipitation, relativehumidity, atmospheric pressure at the ground level,atmospheric stability and mixing height. The elevated PMconcentrations during the 1998 March episode were clearlyrelated to conditions of high atmospheric pressure,relatively low ambient temperatures and low wind speeds inpredominantly stable atmospheric conditions. The resultsprovide indirect evidence indicating that the PM10concentrations originate mainly from local vehiculartraffic (direct emissions and resuspension), while thePM2.5 concentrations are mostly of regionally andlong-range transported origin.  相似文献   

18.
Consortia were developed for the treatment of corncobs for use as a feedstock in a biogas fermentor. The treatment of corncobs with xylanolytic consortia enhanced the production of methane and biogas. All five consortia developed produced the maximum biogas and methane at a 6% loading rate and 20 days hydraulic retention time (HRT). The maximum biogas yield of 0.59m3/kg volatile solids (VS) with a methane content of 62% was produced with the KK-10 consortium. This was apparently due to a maximum hemicellulose degradation of 88%.  相似文献   

19.
Over 7,000 lakes around Sudbury, Ontario, Canada were acidified by S deposition associated with emissions from the Sudbury metal smelters and more distant S sources. Air pollution controls have led to widespread changes in damaged Sudbury lakes, including increased pH and decreased concentrations of SO4, metals and base cations. While chemical improvements have often been substantial, many lakes are still acidified, although water quality recovery is continuing. Biological recovery has been observed in some lakes among various groups of organisms including fish, zooplankton, phytoplankton and zoobenthos. Generally, however, biological recovery is still at an early stage. Lakes around Sudbury are also showing that the recovery of acid-damaged lakes is closely linked to the effects of other major environmental stressors such as climate change, base cation depletion and UV-B irradiance. Future studies of the recovery of acid-damaged lakes around Sudbury, and in other regions, will need to consider the interactions of these and other stressors.  相似文献   

20.
Starch granules were modified with trisodium trimetaphosphate (TSTP) and characterized by P31-NMR, FTIR and DSC. Seventy-micron films were prepared from modified starch and polycaprolactone blends by solvent casting technique. Three different types of films—PCL (100% polycaprolactone), MOD-ST/PCL (50% modified starch and 50% polycaprolactone blend) and NONMOD-ST/PCL (50% nonmodified starch and 50% polycaprolactone blends)—were prepared, and their thermal, mechanical, and morphologic properties were investigated to show the increased performance of PCL with the addition of starch and also the effect of modification. It was observed that with the addition of starch the Young's modulus of polycaprolactone was increased and became less ductile, whereas tensile strength and elongation at break values decreased. Biodegradation of these films was inspected under different aerobic environments with the presence of Pseudomonas putida, activated sludge, and compost. It was observed that whereas P. putida had almost no effect on degradation during 90 days, with the presence of activated sludge, considerable deformation of films was observed even in the first 7 days of degradation. In a compost environment, degradation was even faster, and all polymer films were broken into pieces within first 7 days of degradation and no film remained after 15 days.  相似文献   

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