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1.
用铬渣生产水泥消除铬消毒性的研究   总被引:1,自引:0,他引:1  
本文提出了一种通过以粉煤灰(或煤矸石),石灰石,铬渣,A渣为原料煅炼新型低温水泥的方法去除儿渣毒性,进行了去除铬渣毒性稳定性试验,讨论了除铬渣毒性的机理和影响去除铬渣毒性的因素,试验结果表明,该法去除铬渣毒性彻底,社会效益及经济效益显著,是处理铬渣的一种有效方法。  相似文献   

2.
本文提出了一种通过以粉煤灰(或煤矸石)、石灰石、铬渣、A渣为原料煅烧新型低温水泥的方法去除铬渣毒性;进行了去除铬渣毒性稳定性试验;讨论了去除铭渣毒性的机理和影响去除铬渣毒性的因素;试验结果表明,该法去除铬渣毒性彻底,社会效益及经济效益显著,是处理铬渣的一种有效方法。  相似文献   

3.
铬渣作水泥矿化剂的经济及环境效应分析   总被引:1,自引:0,他引:1  
铬渣的处理利用一直是铬盐行业和固体污染物处理的难点,本文介绍了用铬渣作水泥矿化剂处理铬渣这种新方法的原理,并进行了经济和环境效应分析,结果表明用铬渣作水泥矿化剂确实是一种很好的处理铬渣的方法。  相似文献   

4.
利用黄磷厂废渣作煅烧水泥熟料的矿化剂、水泥混合材和利用黄磷厂废渣生产胶凝材、白水泥是消除黄磷渣污染环境的有效途径;通过影响黄磷渣作水泥混合材和生产胶凝材因素的研究,推荐了提高黄磷渣作水泥混合材的掺量及生产优质胶凝材的工艺条件;黄磷渣的开发利用不仅可使企业获得显著的经济效益,而且可减少磷渣堆放占用耕地和消除磷渣对环境的污染,具有显著的经济效益、社会效益和环境效益。  相似文献   

5.
本文对电石渣在建材、环保、化工等多个行业中的应用情况进行了分析,并着重介绍了电石渣替代石灰石生产水泥的工艺。  相似文献   

6.
随着生活垃圾焚烧处理方式的不断推广,焚烧底渣的产生量也不断增加。按照我国的固体废物分类方法,底渣属于一般固体废物,无需进一步处置而可直接进入环境。实验结果表明,底渣中的重金属和多环芳烃可以被浸出而迁移进入环境。重金属的浸出浓度受到水相pH值和底渣粒度的影响,初期的浸出浓度最大。在底渣浸出液中,可以检测到8种环数≤4的多环芳烃,其中菲的浸出浓度最大(超过10ng/mL)。实验结果显示,底渣中的多环芳烃对环境造成的二次污染比较严重。  相似文献   

7.
浅谈湿法炼锌工艺的浸出渣问题   总被引:4,自引:0,他引:4  
刘斌  王伟涛 《四川环境》2007,26(2):105-108
湿法炼锌已占据世界炼锌总量的80%以上,是世界炼锌生产的发展方向,而湿法炼锌中产出的锌浸出渣可能带来的环境污染及其防治,成为该类项目中需要关注的重要问题之一。本文对锌浸出渣的产生、处理过程中的污染环节以及可能带来的环境影响进行了分析,并根据作者的工作实践,提出了防止锌浸出渣处理过程产生污染的措施,具有一定的参考价值和指导意义。  相似文献   

8.
日本钢铁渣资源化利用技术   总被引:3,自引:0,他引:3  
日本钢铁渣资源化利用技术ProgressonTurningStealSlagIntoEnergyinJapan许亚华近年日本钢铁工业总渣量约4000万吨,其中以高炉渣量为主,其次是钢渣。日本在钢铁渣资源化方面做了大量工作,1976年在铁钢联盟内成立“...  相似文献   

9.
煤灰渣利用中对人群所产生辐射影响的评价   总被引:1,自引:0,他引:1  
煤的开发与利用产生了大量的灰,渣等固体废物,占用大量土地,污染土壤和水源,成为四大公害之一,因而对煤灰,渣的治理和综合利用一直受到人们的关注。然而,由于煤灰渣中的天然放射性水平较高,因此,在煤灰渣的综合利用,尤其在用作建筑材料时,不可避免地要受到其放射性核素的危害。本文在对四川省各燃煤电厂排放灰渣中的^238U,^232Th,^220R,^40X并无然放射性核素进行分析和研究的基础上,用UNSCEAR1982年报告所推荐的计算模式估算了各电厂煤灰渣制度建材对公众所产生的附加辐射剂量,评价了煤灰制度建材对环境和人群所产生的辐射影响,并提出了控制煤灰渣在建材中的最大掺合量,为其它作用的使用煤灰渣提出了科学的理论依据。  相似文献   

10.
本文较系统地研究了影响黄磷渣作水泥混合材的因素;推荐了提高黄磷渣作水泥混合材的掺量必须控制的条件;按推荐的控制条件,黄磷渣作水泥混合材的掺量可高达40%以上。  相似文献   

11.
The Indo‐Gangetic plain is characterized by intensive agriculture, largely by resource‐poor small and marginal farmers. Vast swathes of salt‐affected areas in the region provide both challenges and opportunities to bolster food security and sequester carbon after reclamation. Sustainable management of reclaimed soils via resource conservation strategies, such as residue retention, is key to the prosperity of the farmer, as well as increases the efficiency of expensive initiatives to further reclaim sodic land areas, which currently lay barren. After five years of experimentation on resource conservation strategies for rice‐wheat systems on partially reclaimed sodic soils of the Indo‐Gangetic region, we evaluated changes in different soil carbon pools and crop yield. Out of all resource conservation techniques which were tested, rice‐wheat crop residue addition (30% of total production) was most effective in increasing soil organic carbon (SOC). In rice, without crop residue addition (WCR), soils under zero‐tillage with transplanting, summer ploughing with transplanting and direct seeding with brown manuring showed a significant increase in SOC over the control (puddling in rice, conventional tillage in wheat). In these treatments relatively higher levels of carbon were attained in all aggregate fractions compared to the control. Soil aggregate sizes in meso (0.25‐2.0 mm) and macro (2‐8 mm) ranges increased, whereas micro (< 0.25 mm) fractions decreased in soils under zero‐till practices, both with and without crop residue addition. Direct seeding with brown manuring and zero tillage with transplanting also showed an increase of 135% and 95%, respectively, over the control in microbial biomass carbon, without crop residue incorporation. In zero tillage with transplanting treatment, both with and without crop residue showed significant increase in soil carbon sequestration potential. Though the changes in accrued soil carbon did not bring about significant differences in terms of grain yield, overall synthesis in terms of balance between yield and carbon sequestration indicated that summer ploughing with transplanting and zero tillage with transplanting sequestered significantly higher rates of carbon, yet yielded on par with conventional practices. These could be appropriate alternatives to immediately replace conventional tillage and planting practices for rice‐wheat cropping systems in the sodic soils of the Indo‐Gangetic region.  相似文献   

12.
Seven mixtures from four organic residues—an aerobic sewage sludge, a city refuse, a peat residue, and a grape debris—were composted, and the changes undergone by their different carbon fractions during their composting and maturation were studied. In most cases a decrease in carbon fractions during the composting and maturation processes was observed. The extractable carbon, however, increased during maturation. Organic matter mineralization was greater in the composts with city refuse than in those with sewage sludge. The samples with peat residue showed the lowest decreases in carbon fractions. During maturation, an increase of humiclike fraction was observed, which was reflected by a decrease in the soluble carbon-precipitated carbon ratio at pH 2. Water-soluble carbon was the carbon fraction most easily degradable by microorganisms, and its amount correlated significantly with composting time in all the samples.  相似文献   

13.
Shredder residue is the residue from the shredding of end-of-life vehicles and white goods, after removal of the main metals. Approximately 850,000 tonnes of shredder waste is produced in the UK each year, and historically sent to landfill. Due to European legislation such as the End-of-Life Vehicle (ELV) Directive and the Landfill Directive there is pressure to minimise this waste through recycling and recovery.In this paper, primary data are presented showing that 40% of materials are potentially recoverable in the coarser fraction of UK automotive shredder residue (>30 mm). Barriers to such recycling are discussed in the context of several recent drivers, including this waste's possible reclassification as hazardous.The lack of full and timely implementation of the ELV Directive in the UK has made it an ineffective driver, and it is now unlikely that its 2006 recycling targets will be met as intended.  相似文献   

14.
Elevated atmospheric CO2 can result in larger plants returning greater amounts of residue to the soil. However, the effects of elevated CO2 on carbon (C) and nitrogen (N) cycling for different soybean varieties have not been examined. Aboveground residue of eight soybean [Glycine max (L.) Merr.] varieties was collected from a field study where crops had been grown under two different atmospheric CO2 levels [370 micromol mol(-1) (ambient) and 550 micromol mol(-1) (free-air carbon dioxide enrichment, FACE)]. Senesced residue material was used in a 60-d laboratory incubation study to evaluate potential C and N mineralization. In addition to assessing the overall effects of CO2 level and variety, a few specific variety comparisons were also made. Across varieties, overall residue N concentration was increased by FACE, but residue C concentration was only slightly increased. Overall residue C to N ratio was lower under FACE and total mineralized N was increased by FACE, suggesting that increased N2 fixation impacted residue decomposition; total mineralized C was also slightly increased by FACE. Across CO2 levels, varietal differences were also observed with the oldest variety having the lowest residue N concentration and highest residue C to N ratio; mineralized N was lowest in the oldest variety, illustrating the influence of high residue C to N ratio. It appears (based on our few specific varietal comparisons) that the breeding selection process may have resulted in some varietal differences in residue quality which can result in increased N or C mineralization under elevated CO2 conditions. This limited number of varietal comparisons indicated that more work investigating varietal influences on soil C and N cycling under elevated CO2 conditions is required.  相似文献   

15.
沼渣连续施用对土壤微生物量碳、氮剖面分布的影响   总被引:1,自引:0,他引:1  
通过"棉花+小麦"轮作施用沼渣的定位试验,研究不同年限的沼渣施用对土壤剖面微生物量C、N(MBC、MBN)分布特征的影响。结果表明:在0~50cm剖面上,施用沼渣1年对0~30cm土壤的MBC、MBN影响较大,能显著提高30~40cm土层土壤MBC、MBN的含量,施用沼渣5年时对40~50cm土层MBC、MBN无明显影响。土壤MBC、MBN含量总体随施用沼渣年限的延长而增加,各土层MBC、MBN含量增幅随着施用年限的延长呈现不同趋势。施用沼渣1年,耕层土壤的MBC/MBN值较习惯耕作增加,施用沼渣3年后,其值呈降低趋势。各土层的MBC/TOC、MBN/TN和MBC的变化趋势基本一致,总体随着沼渣施用年限的延长而增加。针对"棉花+小麦"轮作模式,持续施用沼渣3年更有利于改善0~40cm土层土壤肥力。  相似文献   

16.
Lignocellulosic materials are good precursors for the production of activated carbon. In this work, coffee residue has been used as raw material in the preparation of powder activated carbon by the method of chemical activation with zinc chloride for the sorption of Pb(II) from dilute aqueous solutions.The influence of impregnation ratio (ZnCl2/coffee residue) on the physical and chemical properties of the prepared carbons was studied in order to optimize this parameter. The optimum experimental condition for preparing predominantly microporous activated carbons with high pore surface area (890 m2/g) and micropore volume (0.772 cm3/g) is an impregnation ratio of 100%. The developed activated carbon shows substantial capability to sorb lead(II) ions from aqueous solutions and for relative impregnation ratios of 75 and 100%, the maximum uptake is practically the same. Thus, 75% represents the optimal impregnation ratio.Batch experiments were conducted to study the effects of the main parameters such as contact time, initial concentration of Pb(II), solution pH, ionic strength and temperature. The maximum uptake of lead(II) at 25 °C was about 63 mg/g of adsorbent at pH 5.8, initial Pb(II) concentration of 10 mg/L, agitation speed of 200 rpm and ionic strength of 0.005 M. The kinetic data were fitted to the models of pseudo-first order and pseudo-second order, and follow closely the pseudo-second order model. Equilibrium sorption isotherms of Pb(II) were analyzed by the Langmuir, Freundlich and Temkin isotherm models. The Freundlich model gives a better fit than the others.Results from this study suggest that activated carbon produced from coffee residue is an effective adsorbent for the removal of lead from aqueous solutions and that ZnCl2 is a suitable activating agent for the preparation of high-porosity carbons.  相似文献   

17.
US Federal law mandates that mined land be returned by mine operators to a condition capable of supporting its pre-mining use or a higher use. Previously forested lands have commonly been reclaimed to hayland/pasture or wildlife habitat, and most of these lands have been abandoned from management and rendered non-productive. This situation has left landowners in the position of converting these reclaimed mined lands to forests at a later date, if they choose to make them economically productive. Such land-use conversion, however, comes with a substantial up-front cost to the landowner, which makes the financial viability of such a conversion questionable. We examine the financial viability of reforestation of these previously reclaimed mine lands by calculating land expectation value (LEV) under a range of conditions that include forest type, site quality, and reforestation intensity. We find that conversion to white pine is viable on higher quality sites under low to moderate interest rates with low or high timber prices, but conversion to mixed hardwoods is only profitable under the high price scenario with low interest rates, and only on higher quality sites. We also consider the implications of a shift in reforestation burden from the landowner to the mine operator, and results suggest that including costs of reforestation as part of the mining operation creates a financially viable forest enterprise for landowners under all scenarios for both white pine and mixed hardwoods. Two forms of carbon payments that could encourage reforestation of previously reclaimed mined lands also are examined: an annual payment based upon the total accumulated carbon found on-site in a given year, and an annual payment based on only the increment of carbon storage each year. Our carbon payment results indicate that annual values of up to $5.17 per ton of carbon stored in hardwoods and $9.39 per ton of carbon stored in pines would be required to make reforestation profitable under the poorest conditions (high interest rates, low prices, and poor quality site) when the payment is based on accumulated on-site carbon, although lower values are required under more favorable scenarios. Payments that are based upon the annual increment of carbon must fall in the range of $8.66–$71.88 per ton of carbon stored in hardwoods and $0–$83.29 per ton of carbon stored in pines to make reforestation financially viable.  相似文献   

18.
黄利华  华坚  尹华强 《四川环境》2006,25(5):9-11,49
以糠醛渣碳粉为原料,配以一定比例的粘结剂和增强材料,制备出了可用于烟气脱硫的蜂窝状活性炭,考察了活化温度对蜂窝状活性炭结构和脱硫性能的影响。结果表明:随着活化温度的升高,样品的比表面积增大,类石墨微晶尺寸减小,类石墨有序结构逐渐变得无序成为乱层石墨结构,样品的脱硫能力增大。  相似文献   

19.
Large but feasible increases that have been projected for the production of wood energy in the United States can be expected to significantly alter the current carbon storage patterns in US forest vegetation. The 1976 net wood increment left after forest cutting equals about 136 × 106 tons of carbon/year, with about 60% of the increment found in merchantable trees, and the remainder in nonmerchantable components.Achieving 5–10 quads of wood energy beyond 1976 levels by the year 2010 can significantly change current carbon storage patterns with the magnitude of change dependent on the extent of residue harvest to meet energy goals, and the rate of future forest growth. Complete loss of the apparent net wood increment is a possible outcome.Although the future growth and harvest situation cannot be known now, a range of possible scenarios suggests that US forests in the year 2010 will store much less carbon than today, thus significantly changing their role in the global carbon cycle.  相似文献   

20.
以糠醛渣、酚醛树脂和一定的造孔剂为原料制备球形活性炭,考察其碘吸附值和负载金属的性能,结果表明,较好的造孔剂为CMC。同时,通过浸泡方式在活性炭上负载铜、钒以及铜钒复合物,在不同温度下考察各活性炭的脱硫性能,结果表明,负载钒的活性炭在437K下对SO2的转化有明显的催化作用,而铜、钒负载量的适当增加有利于活性炭吸附性能的提高。  相似文献   

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