Anaerobic treatment of methanolic wastes

Although it is well known that methanol can be fermented directly by a specific species of methane bacteria, viz. Methanosarcina barkeri, until now little information was available about the effect of important environmental factors on the anaerobic fermentation of methanol. As methanol can be the main pollutant in some specific chemical wastes and may be formed under natural conditions (e.g. in marshes) as intermediate in the decomposition of organic matter, more information about the effect of environmental factors is required. In this study the effect of pH, bicarbonate alkalinity and trace elements on the methane fermentation of pure aqueous solutions of methanol has been investigated. Methanol was found to be still fermented at pH values as low as 3.5. The optimal pH range is presumed to lie between pH 5.5 and 6.0. No exact figures can be given yet about the optimal pH range, because pH values higher than 6.0 could not be maintained in a well digesting system (due to the formation of volatile fatty acids (VFA) from methanol), except if no trace element solution was supplied to the influent. In the absence of trace elements the formation of VFA from methanol proceeds fairly slowly, but the conversion of methanol to methane is also slower in that case.In the presence of trace elements a significant fraction, directly depending on the HCO₃⁻ concentration, is converted to VFA, mainly consisting of acetic acid and butyric acid. The VFA formation from methanol was found to be more sensitive to a low pH shock (e.g. from pH 3.5 to 4.0) and slows down more rapidly with decreasing pH than the formation of methane. Concerning the anaerobic treatment of wastes containing methanol as the main pollutant, it is not yet possible to decide upon a one-step or a two-step process, e.g. with a separate acid formation and methane fermentation step.     

基于循环经济的建筑垃圾回收利用技术研究

主要论述了循环经济的减量化、资源化和无害化原则在建筑垃圾管理中的具体运用以及建筑垃圾资源化应注意的问题,并在此基础上,提出了建筑垃圾管理的一些建议,以此来呼吁全社会的人们都来关注和参与建筑垃圾的减量化、资源化和无害化,增强人们节约资源、保护环境的意识。并希望这些建议能为政府有关的职能部门在建筑垃圾管理方面提供科学的参考依据。     

加快废弃物处理的产业化促进废弃物转化为可用资源

吉林省光大实业集团按照党的十六大所确立的“支持东北地区等老工业基地加快调整和改造,支持以资源开采为主的城市和地区发展持续产业”的方针和国务院[2003]11号文件精神,为把资源已枯竭的营城煤矿堆存多年、占地又污染严重的煤矸石变废为宝,改造坍陷区的环境,创造下岗人员的就业机会,本着集团公司“以煤矸石等废弃资源综合利用为主的开发新型建材的经营战略”,依托已建成投产的煤矸石烧结空心砖生产线的成熟经验,提出建设一个充分利用废弃资源、科技含量高、经济效益好、资源消耗低、环境污染少、人力资源能得到充分发挥完全符合“节地、…     

建筑废弃物的处理

针对建筑固体废弃物日益增多的现状,探讨了建筑废弃物的种类和危害,分析了其对环境的影响,并提出了我国建筑废弃物的处理和利用方法,从而节约能源,美化生活环境。     

垃圾土的降雨入渗分析

本文通过数值模拟计算了不同初始孔隙水压力和不同降雨条件下的垃圾土的降雨入渗,展示了垃圾土中的水分运移过程,得出了孔隙水压力分布随时间的变化曲线,使得对垃圾土入渗问题的认识更加直观和清楚。同时根据计算结果讨论了不同初始孔隙水压力和不同降雨强度对垃圾土入渗过程的影响,阐述了降雨入渗时的垃圾土中渗流的变化规律,并用试验验证了本文计算结果的合理性。最后模拟了填埋场降雨入渗,揭示了孔隙水压力分布的变化。     

煤及其燃耗过程中产生的三废增值化利用（二）

煤及其燃耗过程中产生的"固、液、气"三废已成为环保减排的重中之重,对其进行资源化综合利用对我国经济和环境具有重要的意义.为此回顾了目前三废低附加值利用已经取得的成果,提出了对三废进行高附加值增值化综合利用的方法,从而实现技术的可持续发展.     

建筑垃圾回收与利用

从垃圾在各国的回收利用情况及建筑垃圾应用途径入手,倡导回收利用建筑垃圾节约能源保护环境,分别探讨了建筑垃圾应用于建筑施工的可行性以及建筑垃圾回收利用中需解决的问题,并提出了一些指导性建议,以期尽可能地降低建筑垃圾对生态环境造成的不利影响。     

Treatment of tetraethyl lead manufacturing wastes

A study was carried out in an effort to find an effective means of treating tetraethyl lead manufacturing process waste waters. The conventional method of coagulation was effective for the removal of inorganic lead compounds in the tetraethyl lead process streams whereas the organic lead compounds present in the waste waters were not amenable to coagulation. Of the various waste waters arising from the tetraethyl lead manufacturing process, those waste waters which are rich in organic lead compounds were passed through a macroreticular sulfonate type strongly acidic cation exchange resin and the exhausted resin was eluted by caustic soda to give eluate containing high concentrations of organic lead compounds. The ion exchange resin was used repeatedly in this way. The organic lead thus concentrated was converted to inorganic lead by the addition of chlorine gas. When the eluate thus enriched in inorganic lead is added to the process streams carrying chiefly inorganic lead and coagulation is carried out, an almost complete elimination of lead in the tetraethyl lead process discharges will be obtained.     

工业废渣在干混砂浆中的应用

随着社会的发展,人们对环境愈加重视,节能减排渗透到经济发展的多个环节,节约能源,变废为宝成为各行各业新的研究方向。本文主要针对天津地区产生的粉煤灰、矿渣等多种工业废渣应用于干混砂浆中的物理指标进行了研究。废渣的掺入起到了改善水泥基材料的综合性能,降低生产成本和减轻环境负荷的作用,既节约了自然资源,又保护了生态环境,值得推广。     

Palm oil refinery wastes treatment

Effluent from the refining of crude palm oil was subjected to physical-chemical and biological treatment. An inclined corrugated parallel plates oil separator spaced at 25 mm was used with hydraulic loading rates of 0.2, 0.5 and 1 m³ m⁻²-h. 91% oil and grease removal could be achieved at 0.2 m³ m⁻²-h. Coagulation and flocculation carried out on batch samples after oil and grease separation revealed that with 100 mg l⁻¹ alum addition BOD was reduced from 3500 to 450 mg l⁻¹ and COD from 8600 to 750 mg l⁻¹ after 30 min settling. Higher doses of alum and doses of polyelectrolyte, activated carbon and sodium hypochloride did not yield significant additional reductions in BOD and COD. Batch dissolved air flotation (DAF) removed 90% of the suspended solids with 2.7% solids in the thickened sludge at an A/S ratio of 0.014. This method yielded the similar effluent quality as the inclined corrugated plates oil and grease separator. Field data from a DAF plant compare closely with data achieved in this study. Activated sludge treatment on the effluent from the oil separator yielded a BOD of 46 mg l⁻¹ with a loading rate of 0.3 g BOD (g MLVSS)⁻¹-day. Total dissolved solids (TDS) remained high and removal through coagulation and chemical oxidation brought the COD level down to around 180 mg l⁻¹. Biokinetic coefficients Y, k_dK and K₃ were found to be 0.85 g VSS (g BOD)⁻¹, 0.016 day⁻¹, 0.12 g BOD (g VSS)⁻¹-day and 510 mg l⁻¹ BOD respectively.     

煤及其燃耗过程中产生的三废增值化利用（一）

煤及其燃耗过程中产生的固、液、气三废已成为环保减排的重中之重,对其进行资源化综合利用对我国经济和环境具有重要的意义.为此回顾了目前三废低附加值利用已经取得的成果,提出了对三废进行高附加值增值化综合利用的方法,从而实现技术的可持续发展.     

Cement-bonded composites from lignocellulosic wastes

A large quantity of lignocellulosic wastes is generated worldwide from various sources such as agriculture, construction, wood and furniture industries leading to environmental concerns. Use of these wastes in making cement-bonded construction materials can reduce the magnitude of the problems. However, in this effort there are various restraints like compatibility of these wastes with cement, their toxicity, and limited composite strength. This paper reviews the results of recent research into the use of these wastes in making cement-bonded composites used as building materials. The approaches like pre-treatments, use of chemical admixtures and modified manufacturing process, adopted to overcome the aforementioned drawbacks are described. The benefits and limitations of the use of such materials in building are also discussed.     

Mercury removal from petrochemical wastes

The precipitation of mercury as mercury-starch-xanthate is studied. The process is studied in terms of optimum mercury-xanthate molar ratio, of influence of flocculation sedimentation times and of interferences (aluminum, iron, silica, chloride, organic substances and suspended solids).The studied reaction is advantageously applied to mercury removal from petrochemical wastes. The optimized process is applied both to a simulated and to a real wastewater, coming from a petrochemical industry (ANIC-Ravenna, Italy).     

Reusing ceramic wastes in concrete

The ceramic industry is known to generate large amounts of calcined-clay wastes each year. So far a huge part is used in landfills. Reusing these wastes in concrete could be a win–win situation. For one hand by solving the ceramic industry waste problem and at the same time leading to a more sustainable concrete industry by reducing the use of non renewable resources like cement and aggregates and avoiding environmental problems related to land filled wastes. This paper examines the feasibility of using ceramic wastes in concrete. Results show that concrete with 20% cement replacement although it has a minor strength loss possess increase durability performance. Results also show that concrete mixtures with ceramic aggregates perform better than the control concrete mixtures concerning compressive strength, capillary water absorption, oxygen permeability and chloride diffusion thus leading to more durable concrete structures.     

某铁路局客运公司洗衣车间通风空调设计

结合乌局客运公司洗衣车间的实际状况，介绍了其通风空调设计思路及洗衣房的负荷特点，探讨了送、排风系统的设计要点，以保证洗衣车间内的空气环境。     

谈园林垃圾的资源化利用

根据园林垃圾资源化"利用—再利用"的指导思想,结合国外城市园林垃圾处理的典型做法,对园林垃圾的资源化利用进行了初步的探讨,经归纳分析得出:"落叶化土""堆肥处理""推进管理型环保"等典型的垃圾处理方法在国内都具有一定的适用性。     

陶粒与固体废弃物资源化利用

文章介绍了我国陶粒的产量、品种结构、性能结构及生产企业的现状，阐述了几种固体废弃物生产陶粒的工艺技术，提出了固体废弃物陶粒重点发展的三种新技术。