论无害化处理机关事业单位电子办公垃圾

通过对现有机关事业单位办公垃圾分析,提出处理电子办公垃圾的方法及有效治理措施。     

进口废物原料管理中存在的问题

废物原料主要是指经初加工再生、边角料、残次品等可以作为再生利用原料的废物。加强进口废物原料管理就显得尤为重要。本文首先分析了进口废物原料管理中存在的问题,其次,就如何加强进口废物原料管理进行了较为深入的探讨。     

废弃混凝土在干混砂浆中的应用研究

废弃混凝土的循环再生利用已日益成为人类关注的重要话题,符合环境保护与可持续发展战略的迫切要求。利用废弃混凝土破碎产生的再生细骨料部分取代天然细骨料来配制干混砂浆。通过试验证明:在固定配合比条件下,再生骨料替代率为50%时,干混砂浆抗压强度、保水率和抗冻融性、强度损失率等均符合M5.0中保水的指标要求。     

离子色谱法测定工业废水中丙酸

建立了用离子色谱法测定工业废水中丙酸的方法,结果表明,常规阴离子对本方法的测定没有干扰,校准曲线线性相关系数高,并且能在很大范围内呈现线性。运用该方法实测标样和水样,精密度和准确度都能满足需求,表明该方法测定结果可靠,具有一定的应用价值。对实际废水样品进行分析,丙酸的回收率分别为95．0％～103．8％。本方法分析速度快,所需样品量少,且无需要复杂的前处理,简便、灵敏、可靠。     

LED 外延片芯片制造业工业废水的治理分析

本文介绍了LED外延片芯片制造业工业废水的治理方法,同时,也对废水处理后的回用方法进行了分析。     

食品工业废水资源化处理与利用方法

本文主要通过对食品生产工业废水的基本现状介绍,向大家展示目前问题的严重性,同时提出一些富有建设性的意见,希望有关部门可以采取,为我们的子孙留下一个碧水蓝天。     

Physical and chemical characteristics of waste activated sludge treated with electric field

This study investigates the physical and chemical characteristics of sludge treated with controlled levels of electric field. The results indicated that the potential gradient and contact time strongly influenced the physical and chemical characteristics of sludge. Based on the settling velocity measurements, a potential gradient of 6 V/cm with a treatment time of 10 min is recommended as an optimal condition for improving sludge settling. For sludge disintegration, applying a higher potential gradient and a longer treatment time to the sludge are more efficient than applying lower levels. The results of the experiments presented here show that an electric field not only disintegrates sludge and destroys microbial cells but also removes and solubilizes organic substances. Possible mechanisms of electric field treatment are also discussed.     

How does the operational environment affect utility performance? A parametric study on the waste sector

The urban waste treatment service has been a sensitive issue for the Portuguese governments in the past decades. Among other measures, the environmental and economical issues led to the creation of a sector-specific regulator for the waste sector. Considering this atypical circumstance in the worldwide context it is worth studying the external factors that may influence the waste utilities efficiency along with the regulation role. In this regard, we applied the parametric approach of the stochastic frontier analysis to evaluate the influence of the operational environment on the urban waste services performance. The sample included 32 utilities responsible for the waste treatment service in Portugal. The results showed a negative influence of factors, such as the existence of regulation, the distance to the waste treatment facilities and the provision of other services on utility performance. We also observed some benefits from privatisation and incineration, although these options have some particular features.     

Thermogravimetric pyrolysis of waste polyethylene-terephthalate and polystyrene: A critical assessment of kinetics modelling

Pyrolysis is considered as possible technique to thermally convert waste plastics into chemicals and energy. Literature on experimental findings is extensive, although experiments are mostly performed in a dynamic heating mode, using thermogravimetric analysis (TGA) and at low values of the heating rate (mostly below 30 K/min). The present research differs from literature through the application of far higher heating rates, up to 120 K/min. The use of these dynamic results to define the reaction kinetics necessitates the selection of an appropriate reaction mechanism, and 21 models have been proposed in literature considering the rate limiting step being diffusion, nucleation or the reaction itself.The current research studied the cracking of PET and PS by TGA at different heating rates (temperature ramps). Results were used to check the validity of the proposed mechanisms. Several conclusions are drawn: (i) to obtain fair results, the heating ramp should exceed a minimum value, calculated at 30 K/min for PET and 80 K/min for PS; (ii) application of the majority of the models to experimental findings demonstrated that they do not meet fundamental kinetic considerations and are questionable in their use; and (iii) simple models, with reaction order 1 or 2, provide similar results of the reaction activation energy.A further comparison with literature data for dynamic and isothermal experiments confirms the validity of these selected models. Since TGA results are obtained on a limited amount of sample, with results being a strong function of the applied heating rate, the authors believe that isothermal experiments, preferably on a large scale both towards equipment and/or sample size, are to be preferred.     

An interval-based regret-analysis method for identifying long-term municipal solid waste management policy under uncertainty

In this study, an interval-based regret-analysis (IBRA) model is developed for supporting long-term planning of municipal solid waste (MSW) management activities in the City of Changchun, the capital of Jilin Province, China. The developed IBRA model incorporates approaches of interval–parameter programming (IPP) and minimax–regret (MMR) analysis within an integer programming framework, such that uncertainties expressed as both interval values and random variables can be reflected. The IBRA can account for economic consequences under all possible scenarios associated with different system costs and risk levels without making assumptions on probabilistic distributions for random variables. A regret matrix with interval elements is generated based on a matrix of interval system costs, such that desired decision alternatives can be identified according to the interval minimax regret (IMMR) criterion. The results indicate that reasonable solutions have been generated. They can help decision makers identify the desired alternatives regarding long-term MSW management with a compromise between minimized system cost and minimized system-failure risk.