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以农林废弃物等生物质为原料制备各种新型吸附剂,既实现了对农林废弃物的资源再利用,也可以用其简单高效处理各类污染物废水。本文主要综述了以农林废弃物为原料制备生物炭,用以去除环境中污染物的研究进展,讨论了生物炭的制备和改性方法,以及其在治理重金属离子、有机污染物、新污染物,以及土壤修复和“碳中和”等方面的应用,并对生物质类吸附材料在未来环境污染治理中的发展方向进行了展望。 相似文献
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污泥生物炭中氮硫元素含量高,其氮硫行为和环境效应对全球气候变化的影响不容忽视。以往的研究中,研究者往往以富碳生物炭作为主要研究对象,关注碳对全球气候变化的行为和功效,而对氮硫元素的作用关注不够。本文从原始污泥基本性质到其热解过程,再到生物炭的老化,逐步对污泥生物炭整个生命周期内氮硫的行为及其环境效应研究进行综述,并对未来应注重开展的研究方向进行展望,为生物炭中氮硫元素固定、释放及与之关联的环境效应和温室气体排放控制研究提供理论基础。分析表明,污泥中氮元素含量普遍高于硫元素,且热解过程中氮比硫更容易转移至气相产物。氮硫元素随热解温度的增加,在三相产物中的分配都是炭中持续减少,油中先增后减,气中一直增加。高温(>800℃)条件下,气相中的氮含量高于固相,而硫元素则仍然主要存在于固相中。污泥生物炭老化及其环境效应研究表明,污泥生物炭氮硫元素与土壤的相互作用及其温室效应问题在今后的研究中应引起重视。 相似文献
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介绍了生物炭的制备、改性及表征,尤其是在环境修复中的应用。阐述了生物炭常用的制备方法包括热解法、气化法和水热碳化法,指出生物炭的制备原料和条件决定了生物炭的吸附性能。为了提高生物炭的吸附性能,常通过酸、碱、氧化剂、金属氧化物、有机化合物、紫外辐射、等离子体、复合材料、蒸汽及气体吹扫等方式对其进行改性处理,而改性方法的选择主要取决于应用的环境领域。虽然生物炭已在土壤修复及改良、固碳、有机固废堆肥、废水净化及大气污染治理等领域取得了良好的效果,但是生物炭的固碳效果还需要在不同土壤条件进一步验证,生物炭提高土壤质量的原因还需要进一步研究,生物炭去除土壤中有机污染物的作用机理也有待进一步探明。此外,利用生物炭进行环境修复时,应注意生物炭的稳定性问题,以免造成二次污染。综上所述,生物炭在环境修复中具有广阔的应用前景,但也存在一些问题和挑战需要解决。 相似文献
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好氧堆肥是实现有机固体废物无害化、稳定化以及资源化的有效手段。近年来,生物炭作为一种堆肥调理剂在优化堆肥环境参数、加速堆肥进程与提升堆肥品质等方面显示出广阔的前景。生物炭具有丰富的多孔结构和巨大的比表面积以及高效的持水能力、阳离子交换能力和吸附能力,这些性质对促进堆肥进程有巨大优势,比如强化微生物群落活性、促进有机物降解与腐殖质形成、减少臭气和温室气体排放、降低重金属和抗生素以及其他污染物的生物有效性等。本文综述了生物炭在不同类型有机废弃物好氧堆肥过程中的作用,总结了基于生物炭的强化手段在堆肥中的应用,并提出了生物炭未来研究的发展方向,旨在从功能材料方面优化好氧堆肥工艺,并为生物炭在好氧堆肥中的应用提供理论依据和数据支撑。 相似文献
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作为废水处理过程的副产物,污泥的高效处理处置是环保领域的难题之一。通过高温热解将污泥转化为生物炭是一种有效的污泥资源化途径。污泥生物炭不仅可作为“吸附剂”吸附去除水体中污染物,还可作为新型“催化剂”高效催化高级氧化过程以降解水体中的有机污染物。本文综述了近些年来国内外关于污泥生物炭在高级氧化技术领域尤其是催化过硫酸盐(PS)、过氧化氢(H2O2)、臭氧(O3)以及光催化等氧化过程降解有机污染物的研究进展。通过探讨污泥生物炭的表面官能团、掺杂改性杂原子、负载过渡金属及其氧化物以及与其他技术耦合催化降解有机污染物的研究现状,进一步揭示污泥生物炭催化作用的关键活性位点以及催化机理。最后提出该领域目前面临的主要问题及未来发展方向,为污泥生物炭进一步实现高附加值资源化利用提供重要参考。 相似文献
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Intermediate pyrolysis reactors are preferred for processes focused on the production of high-quality biochar. The main types are rotary drums, augers, and moving beds agitated with either grates or paddles. These reactors are usually operated in continuous mode, and are designed to provide a pure, homogeneous biochar product by ensuring near plug flow of the reacting particles. There is a need for laboratory reactors that can provide enough biochar for testing in applications such as soil amendment, fillers for concrete or polymers, coke substitution, or pollutant capture. The pyrolysis shaker reactor (PSR) is a new laboratory reactor that is inexpensive, provides good mixing and temperature control, is easy to operate and allows for rapid turnaround between runs. It provides a homogeneous biochar product. Its use was demonstrated with digestate from the anaerobic digestion of food waste. The rapid and thorough testing program made possible with the PSR indicated that this digestate should be pyrolyzed at 250°C to maximize the release of mineral from the biochar to water, and at 400°C to minimize the release of minerals. Its biochar would require post-treatment to be applied as a substitute for activated carbon. 相似文献
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产生于生物脱氮过程的N2O是一种强效的温室气体并会导致臭氧层破坏。本文综述了污水脱氮过程中N2O的产生机理及影响因素。羟胺氧化和AOB反硝化是硝化过程产生N2O两种主要路径,诸如溶解氧、氨氮和亚硝酸盐等因素主要通过影响微生物的活动或酶的活性而间接影响硝化过程中N2O的产生。反硝化过程是N2O的另一重要产生来源,其N2O生成量的多少与N2O酶有直接关系,而溶解氧、有机碳源和亚硝酸盐等因素会影响反硝化过程中N2O酶的活性。目前新型脱氮工艺也成为N2O的潜在来源,但其N2O产生机理还有待深入研究。尽管N2O释放与周围环境变化密切相关,但本质原因还是由于微生物的作用及酶活性受到影响所致。文章最后指出污水生物脱氮过程中N2O产量控制与减量化策略是今后研究的主要方向,并给出了几点建议。 相似文献
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The clean development mechanism (CDM) of the Kyoto Protocol offers developing countries the opportunity to participate in the effort to reduce global greenhouse gas levels and also benefit from sustainable development opportunities. To date, the majority of CDM investments have gone to emerging markets such as China, India, Brazil, and Mexico, while developing countries such as Nigeria have largely been absent from the program. Chemical sequestration using aqueous ammonia process (AAP) offers a clean low carbon technology for the efficient conversion of captured CO2 into clean CO2 which could be injected into oil field for enhanced oil recovery or as fertilizer source. CDM-CCS (carbon capture and storage) project with AAP has the potential as intervention for leveraging sustainable livelihood development (organic fertilizer for food production) as well as for tackling local (land air and water) and global pollution (reduce methane, SOx and NOx emissions). 相似文献
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Per Weslien Tobias Rütting ?sa Kasimir-Klemedtsson Leif Klemedtsson 《Nutrient Cycling in Agroecosystems》2012,94(2-3):249-253
The emissions of the greenhouse gas nitrous oxide (N2O) were measured from a non nitrogen fertilized carrot (Daucus carota ssp. sativa) field on an organic soil in Sweden during one cropping and post-harvest season. The cumulative emission during the measuring period of 149?days was 41 (±2.8) kg N2O ha?1. Dividing the measuring period into a cropping and a post-harvest period revealed that the presence of carrots strongly stimulated N2O emissions, as the emission during the cropping period was one order of magnitude higher compared to the post-harvest period. The N2O emission from the carrot field were higher than fluxes reported from cereal crop and grass production, but in the same order as reported fluxes from vegetable cropping on organic soils. In conclusion, our results indicate that the cultivation of root vegetable, such as carrots, on organic soil can be a high point source for N2O emissions. 相似文献
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The production of energy in Pakistan as a developing country mainly depends on consumption of fossil fuels, which are the main sources of greenhouse gas (GHG) emissions. These emissions can be mitigated by implementing carbon capture and storage (CCS) in running plants. An overview of the current and future potentials of Pakistan for CCS is provided, indicating a great potential for this technology to capture CO2 emissions. The amine CO2 capture process as the most mature procedure is currently applied in many oil and gas companies in Pakistan, which can be employed to capture CO2 from other industries as well. Pakistan has a great CO2 storage potential in oil, gas, and coal fields and in saline aquifer as well as significant resources of Mg and Ca silicates suitable as feedstock in the carbon mineralization process. For further development and implementation of CCS technologies in Pakistan, economic and policy barriers as the main obstacles should be alleviated. 相似文献
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Meinan Zhen Benru Song Xiaomei Liu Radhika Chandankere Jingchun Tang 《中国化学工程学报》2018,26(12):2592-2600
Organophosphorus pesticides (OPPs) are a set of toxic persistent organic pollutants (POPs) present in the environment. Recently, biochar-mediated bioremediation has exhibited many advantages over conventional methods for the remediation of pesticide-contaminated soil. In the present study, biochar and nitrogen fertilizer (NH4NO3) were employed to remediate OPP-contaminated soil and the greenhouse gas (GHG) emission during 90 days of incubation was investigated. After thermal desorption treatment, the content of organophosphorus pesticides reduced from 175.61 μg·kg-1 to 62.68 μg·kg-1. The addition of NH4NO3 in the following bioremediation led to larger reduction (34.35%) of the pesticide concentration than that of biochar (31.90%) for the contaminated soils with thermal desorption treatment, while the simultaneous addition of biochar and NH4NO3 led to the largest reduction of pesticide concentration (11.07%) for the soil without thermal desorption treatment. The addition of biochar and NH4NO3 only slightly increased the emission rate of GHGs from the soil without thermal treatment, but remarkably increased the emission rate of GHGs from the soil after thermal treatment. In most cases, the addition of NH4NO3 is more effective than biochar to promote the degradation of pesticide, but also exhibited higher GHG emission. The microbial community analysis suggests that the enhanced degradation of pesticide is mainly owing to the increased activity of microorganism. 相似文献