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201.
202.
The organic fraction of a municipal solid waste was added in different doses to an eroded soil formed of loam and with no
vegetal cover. After three years, the changes in macronutrient content and the chemical-structural composition of its organic
matter were studied. The addition of the organic fraction from a municipal solid waste had a positive effect on soil regeneration,
the treated soils being covered with spontaneous vegetation from 1 yr onwards. An increase in electrical conductivity and
a fall in pH were noted in the treated soils as were increases in macronutrients, particularly N and available P and the different
carbon fractions. Optical density measurements of the organic matter extracted with sodium pyrophosphate showed that the treated
soils contained an organic matter with less condensed compounds and with a greater tendency to evolve than the control. A
pyrolysis-gas chromatography study of the organic matter extracted with pyrophosphate showed large quantities of benzene both
in the treated soils and control; pyrrole was also relatively abundant, although this fragment decreased as the dose rose.
Xylenes and pyridine were present in greater quantities in the control and furfural in the treated soils. Three years after
addition to the soil, the organic matter had a higher proportion of fragments derived from aromatic compounds and a smaller
proportion derived from hydrocarbons. Similarity indices showed that, although the added and newly formed organic matter 3
yr after addition continued to differ from that of the original soil and to be more mineralizable, the transformations it
has undergone made it more similar to the original organic matter of the soil than it was at the moment of being added. 相似文献
203.
固体废物管理技术进展 总被引:2,自引:1,他引:2
概述了固体废物管理技术近年来的主要进展,这些进展包括,固体废物从“摇蓝到坟墓”的全过程管理,即从废物产生到收集、运输贮存,再循环,再利用,处理直至最终处理过程所涉及到的:废物最小量化管理技术;废物转移跟踪管理中产生者,运输者,处理处理者,主管当局的职责、主管当局的职责,义务和管理方式;废物经营者向主管当局申请许可证的程序和申请。时,对废物交换制度和废物管理信息系统也作了概要介绍。 相似文献
204.
A solid phase extraction procedure (SPE) is described for the quantitative analysis of polycyclic aromatic hydrocarbons (PAHs) in atmospheric particulate matter (PM), as ubiquitous environmental pollutants routinely measured in air quality monitoring. A SPE cartridge was used based on a molecular imprinted polymer (MIP-SPE) properly tailored for selective retention of PAHs with 4 and more benzene fused rings. The performance of the clean-up procedure was evaluated with the specific concern of selective purification towards saturated hydrocarbons, which are the PM components mostly interfering GC analysis of target PAHs. Under optimized operative conditions, the MIP-SPE provided analyte recovery close to 95% for heavier PAHs, from benzo(α)pyrene to benzo(ghi)perylene, and close to 90% for four benzene rings PAHs, with good reproducibility (RSDs: 2.5%-5.9%). Otherwise, C17-C32 n-alkanes were nearly completely removed. The proposed method was critically compared with Solid Phase Micro Extraction (SPME) using a polyacrylate fiber. Both methods were successfully applied to the analysis of ambient PM2.5 samples collected at an urban polluted site. Between the two procedures, the MIP-SPE provided the highest recovery (R% ≥ 93%) for PAHs with 5 and more benzene rings, but lower for lighter PAHs. In contrast, SPME showed a mean acceptable R% value (∼ 80%) for all the investigated PAHs, except for the heaviest PAHs in the most polluted samples (R%: 110%-138%), suggesting an incomplete purification from the interfering n-hydrocarbons. 相似文献
205.
聚乙烯塑料类固体废弃物热裂化研究 总被引:1,自引:0,他引:1
在反应温度455-495℃,氢气压力0.1~4.0MPa和反应时间2~12h的范围内,就聚乙烯塑料类固体废弃物热裂化时温度、压力和反应时间的影响以及不同反应条件下产物的碳数分布、馏程变化进行了探讨,得出适合于生产柴油馏分的反应条件是温度475℃,常压或低压,反应时间4h等。 相似文献
206.
207.
固体废物取样,制样方法研究 总被引:4,自引:0,他引:4
要采取、制备具有代表性的固体废物样品,从而获得精确的、可靠的监测分析数据,就必须要有科学化、标准化、规范化的样品采取和制备方法。该文对废对取样误差1取样量、取样数、取样点、取样法和制样法等6个方面的问题进行了较详细的论述,为制定我国的固体废物采样、制样技术、制样 重要依据。 相似文献
208.
209.
我国石油炼制企业清洁生产措施分析 总被引:2,自引:0,他引:2
刘春平 《石油化工环境保护》2005,28(3):1-6
石油炼制工业是我国重要的能源和化工原料生产产业。随着生产负荷的提高,加工深度增加,原料变重变差,石油炼制工业的环境保护压力越来越大。针对石油炼制工业的生产特点,分析其污染源、污染治理现状以及目前存在的一些问题,提出了我国石油炼制企业的清洁生产措施。 相似文献
210.
根据近几年对黄土高原地区安太堡露天煤矿废弃土地复垦的系统研究,事实证明新垦土地可超越原有土地生产力及经济效益开发的可行性。认为本地区露天煤矿废弃土地的复垦战略目标应是:借助开矿土地再造的机会,通过科学设计、系统规划,实行大规模地营造农林可利用状态的土地,未来开辟为适宜现代集约经营农林基地;露天煤矿的土地复垦,同时亦应受到社会各方的关注,可在超越矿区范围之外筑坝造田,建设蓄水库等各项工程造福于社会。 相似文献