Extending an ICT4D Computer Re-use Model with E-waste Handling Activities: A Case Study

This paper illustrates how a computer re-use model can be extended to deal with e-waste challenges. First, we describe the re-use of computers as a factor that can help bridge the global digital divide. In an ICT4D context, refurbished computers can be used in developing countries. We describe and illustrate the operating model of such a computer re-use organization, highlighting the different components and interactions of the operating model. Next, we discuss how e-waste puts this computer re-use model under pressure. We argue that the sustainability of computer re-use in an ICT4D context is seriously impacted by this increasing e-waste problem. Finally, we describe how a computer re-use model can be extended and complemented with e-waste handling activities to retain positive effects in an ICT4D context. The paper is based on a single case study.     

110kV交联电缆及附件的回收、再加工和利用

随着近年来城市电网建设力度的加大 ,市区 110kV变电所的重新布点可能导致运行年份不长的 110kV电缆停运 ,停运的 110kV电缆及电缆附件的回收、再加工和利用是城乡电网改造中的课题。     

云南省某企业大理石废浆再利用的探索性研究

针对云南地区以及某企业大理石废浆的特点,制定了废浆处理工艺流程,对大理石石粉进行了用作回收电池铅、除酸剂以及土壤改良剂和制作免烧砖的研究。     

利用中水降低直接空冷电站凝汽器背压的蒸发式冷却系统

国民经济发展需要电力的可靠稳定供给,本文介绍了一种利用经过处理的中水,作为直接空冷电站夏季辅助蒸发式冷却塔的补水,从而实现降低空冷电站夏季凝汽器背压,提高峰荷出力,节约煤耗,同时又实现污水回用,所以是一个节能又节水的系统技术.文中还分析了其推广应用的经济性.     

Disinfection With Peracetic Acid for Domestic Sewage Re-Use in Agriculture

This paper describes a four-month pilot study on peracetic acid disinfection of unchlorinated tertiary effluent for unrestricted re-use in agriculture carried out at West Bari (Italy) sewage-treatment works. Dosages and contact times ranging from 1 to 500 mg/1 and 5 to 60 mins, respectively, indicated that 10 mg/1 of peracetic acid, with a 30-min contact time, achieved the WHO faecal coliform guideline (1000 CFU/100ml). Much higher doses (£400 mg/l and 30 mins) were required to meet the corresponding Californian limit of two colony-forming units/100 ml, which has also been adopted in Italy. Efficient mixing of the disinfectant (in one shot addition) was mandatory - particularly at lower dosages (1–10 mg/l) where there was a higher concentration of suspended solids (>5 mg/l).     

超高层建筑施工装配式安全防护设施设计与应用

针对超高层建筑施工的特点,创新设计了多种用于超高层建筑施工的安全防护措施,主要包括安全防护栏杆、工具式安全防护平挡、定型防护钢板网、抱箍式操作平台、巨型柱空中施工的安全防护平挡等.这些设计实现了安全防护设施工具化、标准化和装配化,为在日后超高层施工中的安全防护施工起到一定的参照作用.     

废水汽提装置的节能实践

在废水汽提装置生产中控制废水冷热进料比、侧线抽出比和氨精制塔温度有利于降低蒸汽单耗；控制上游装置废水总量和实现净化水回用也是废水汽提装置节能行之有效的方法，并取得了一定的经济效益。     

SEWAGE RE-USE IN MAURITIUS

When completed, the sewage-treatment works at St. Martin will serve nearly a third of Mauritius'1.1 million population. In addition to protecting the marine environment, it will provide a valuable source of water to supplement irrigation supplies to west-coast sugar-cane plantations.
This paper explains (i) the treatment-process selection which favoured conventional activated sludge over extended aeration, (ii) the need for nutrient removal, (iii) the choice of UV treatment for disinfection, and (iv) the problem of dye discharges from the textile industry. It also describes the complexity of the control system which is designed to (a) supply tertiary effluent to the irrigation canals blended with surface-water supplies to avoid sodium accumulation in the soils. (b) avoid flooding of the canals, and (c) provide an emergency stormoverflow discharge via the same common outfall pipe to the sea.     

Assessment of ettringite from hydrated FBC residues as a sorbent for fluidized bed desulphurization

The performance of synthetic ettringite as a sorbent in fluidized bed desulphurization has been assessed and compared with that of a commercial limestone. Experiments have been carried out in a bench scale fluidized bed reactor under simulated desulphurizing (steadily oxidizing) combustion conditions. Sorbent performance has been characterized in terms of desulphurization rate, maximum sulphur uptake and attrition propensity. Fluidized bed sulphation experiments have been complemented by microstructural characterization of solid samples, accomplished via X-ray diffraction analysis, scanning electron microscopy and sulphur mapping of cross-sections of particles embedded in epoxy resin.

Experimental results show that both the rate and the maximum extent of sulphur uptake by ettringite significantly exceed those of the limestone. Maximum degree of free calcium utilization is 0.58 for ettringite compared with 0.27 for the limestone. Sulphation tests also indicate that attrition propensity of ettringite is larger than that correspondingly observed for the limestone. Microstructural characterization indicates that sulphation of ettringite takes place evenly throughout the particle cross-section, whereas sulphation of limestone mostly conforms to a core-shell pattern.

Along a parallel pathway, the rate and yield of ettringite formation by hydration of fly ash from a utility fluidized bed boiler have been assessed. Formation of ettringite in these experiments appears to be quantitative upon curing of ash at 70 °C for times up to 4 days.