Hazardous Waste: Future Consideration

In most industries the goods and money move in opposite directions, but in waste management the goods and money travel in the same direction. Consequently to the customer, quality of goods and service might be measured only by price. However, customers are now becoming more sensitive to factors such as environmental quality. They are also becoming aware of the range of disposal options, together with the names of the companies which operate these disposal or treatment sites. Essentially the options are: recyling and recovery, sea disposal, landfill, physico-chemical treatment, solidification, biological treatment and thermal destruction. The Control of Pollution Act 1974 requires that all landfill sites and treatment centres are licensed by the waste disposal authority. These authorities are obliged to act in the public interest, and hence there is a complex interaction of science and politics. This situation often gives rise to localized opposition to facilities which are needed by the community. The UK disposes of 83 per cent of its potentially difficult wastes to landfill whilst Holland disposes of 52 per cent via this route. The cost of disposal varies throughout Europe but, in general, prices in the UK are lower than in Europe, which has led to the importation of wastes from the continent. Economics applies to the waste-disposal industry as much as any other industry, therefore facilities are supplied in response to demand. Price alone will not always be adequate in obtaining the ‘best practical environmental option’. disposal the goods and the money go in the same direction, i.e. to the waste management contractor. This at first sight may not seem important until it is realized that the major control upon the quality of a service is, in fact, the satisfaction with the goods and service which the customer receives. In most cases it is sufficient that the customer disposes of the waste material in a legal manner. However, the judgement of quality of disposal could be of little consequence to him. The factors that concern a customer when he chooses a service include the price, the quality of service, market presentation and reputation. These factors apply in the waste management industry, but the difficulty for the customer is to judge the quality of the service and the market presentation or, more correctly in this case, the quality of operation of the waste contractor. If the latter two factors become difficult to judge, the price becomes a critical factor. This leads to a low standard of operation in the business where price competition becomes more important than the quality of the service. Companies are looking not just for the cheapest legal option but for the best option and what has been referred to as the ‘best practical environmental option’. In the UK the vast majority of hazardous waste disposal is carried out by private-sector companies. Therefore it is essential that the Government sets the correct framework, and that an examination is carried out as to whether the framework is satisfactory and whether it achieves the needs of the Government.     

Land Disposal Practices in Europe and North America

This paper compares the land-based disposal of municipal and hazardous waste in Europe and North America, and the various disposal options are examined for each type of waste. It is concluded that landfill is still the most widely practised disposal method for most wastes in both continents. Other methods include composting, land farming, trenching/spraying, and deep underground disposal. More stringent controls on waste disposal are being introduced and a trend to seek greater uniformity of practice and standards is developing. However, local conditions, such as the nature of the wastes and the availability and nature of disposal sites, continue to work against this trend. There is no single method which is suitable for all wastes and for all conditions. The best environmental option for waste management will vary from place to place and waste to waste, therefore an imposed uniformity of practice is not in the best environmental interest.     

陶瓷废料制备建筑饰面片材的研究

以晋江地区的陶瓷废料主要原料,经过干燥、粉碎,采用偶联剂改性后,添加水泥熟料、减水剂、聚合物乳液和不同添加量的增强纤维,经拌和、成型、干燥制备出建筑饰面片材。制备出的样品性能优异,均能符合现行行业标准《改性无机粉复合建筑饰面片材》JC/T 2219吸水率、耐热性(尺寸变化率)、柔度的技术指标要求,这项研究为晋江地区的陶瓷废料的综合再利用提供了新的途径。     

Using phosphogypsume and boron concentrator wastes in light brick production

In this study, use of wastes produced in phosphoric acid plants and boron concentrators in producing structural brick has been investigated. There are several parameters involved in using these wastes in brick production namely the rate of added waste, firing speed and firing temperature. The performance of these parameters can be measured by several criteria such as natural drying shortening, water absorption and weight loss. Therefore, so many experiments are needed to investigate the effects of these parameters on the bricks produced with these wastes. To this end, around 220 experiments for three different material combinations namely original waste plus normal brick clay, washed waste plus normal brick clay and normal brick clay with no additive were carried out. The results have shown that the industrial wastes produced by phosphoric acid plants can improve the performance of the bricks in terms of drying shortening, weight loss and water absorption.     

Activated carbon by pyrolysis of organic sludges

A study of the feasibility of subjecting organic substances in waste waters to pyrolysis prior to their employment in purification of the water itself is reported. Refinery wastes and those from a biochemical industry were examined. In the case of the refinery wastes, oil filtered on sand granules was carbonized in various gas atmospheres for various periods. The quality of the carbon obtained was determined with reference to its oil-carbon transformation yield, adsorption capacity, and residual hydrocarbon content, comparison being made with a commercial active carbon. Carbon from biochemical wastes was obtained by pyrolysis of the mycelium after fermentation and filtration. This process is promising in that an improvement in the system used for the sludges disposal is required to obtain the active carbon required for the treatment of wastes.     

雨水在城市房屋建筑设计中的利用

城市中人们对水的需求和依赖已越来越大 ,节水问题摆在每一个人的面前。有限的水资源在利用上存在两个方面的问题 ,即浪费和未利用。本文介绍的节水设计 ,以充分利用雨水和减少生活用水为目的 ,结合建筑和结构设计来考虑拦蓄雨水 ,按水质的不同 ,分类利用 ,提高水资源的利用率     

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.     

碱渣回填地下废弃盐腔室内一维沉降试验研究

盐矿水溶开采产出卤水的同时会在地下形成大量的废弃溶腔,而盐化工企业利用采出的卤水制碱时会产生大量的固体废渣（即碱渣）,将碱渣与饱和卤水混合制成浆体注填到废弃盐腔的过程称为碱渣回填废弃盐腔。碱渣在充满卤水的溶腔内的沉降特性对回填效果会产生重要影响,作为初步研究,对两种不同类型碱渣与饱和卤水混合而成的碱渣浆进行了室内一维沉降试验研究。试验发现：黏粒含量少的碱渣浆絮团发育程度低,絮团小而相互独立,沉降类型为絮凝均匀沉降,黏粒含量多的碱渣浆絮团发育程度高,絮团大而联结成网,发生絮网沉降;碱渣浆沉降过程可以分为4个阶段：絮凝阶段、沉降阶段、主固结阶段和次固结阶段;对比两种碱渣的沉降过程发现,发生絮网沉降的碱渣浆在前3个阶段用时均较长;沉降基本结束后,形成的沉积体孔隙比较大,沉积体内仍含有大量的自由水。本研究揭示了两种不同类型碱渣的一维沉降规律,为进一步探索碱渣沉降固结机理及现场碱渣回填废弃盐腔工程提供一定参考。     

Design of the optimal outfall system for a stream receiving thermal and organic waste discharges

A system synthesis technique was employed in the present study for selecting the “best” outfall configuration for a stream that receives multiple thermal and organic waste discharges. The optimal locations for the cooling water and organic waste discharges, the optimal allocations of the wastes to these discharge points, and the optimal artificial aeration control policies were simultaneously determined. A dual water quality constraint on the minimum DO concentration and the maximum BOD concentration was imposed in order to ensure that the water quality be maintained above a minimum legal requirement. The complex pattern search method along with the modified algorithm of the maximum principle was used to generate the required information. A specific example of double-outfall system was solved to illustrate the theoretical development.     

Kinetic study for phosphate removal from water by recycled date-palm wastes as agricultural by-products

The presence of excessive amounts of nutrients including phosphates in water is undesirable. They cause the deterioration of water quality and problems in many natural and engineering systems. The recycling of agricultural waste materials as biosorbents for contaminants removal provides a cheap and ecological means to reduce wastes. This study explored the use of date palm wastes for the effective removal of phosphate from aqueous solutions. Granular date stones (GDS) and palm surface fibres (PSF) as raw abundant waste materials were examined for PO₄ ^-3 removal from aqueous solution. The experimental work was performed in a batch mode to investigate the influence of initial phosphate concentration, contact time, and pH of solution on phosphate biosorption. The FT-IR spectra for the waste materials display many adsorption peaks, confirming the complex nature of the GDS and PSF. Phosphate percentage removal up to 87 and 85% were obtained at initial PO₄ ^-3 concentration of 50 mg as P/L using GDS and PSF, respectively. Due to their low cost and high capability, these types of waste can be used for cost-effective removal of phosphate from wastewater.     

The Impact of Intensive Dairy Farming Activities on River Quality: The Eastern Cleddau Catchment Study

Pollution from farm wastes has been one of the principal causes of deterioration in river quality in recent years. However, little is understood of how, and which, farming activities affect the chemical and biological quality of rivers. To address this problem, a field study has been initiated in the Eastern Cleddau catchment, West Wales, to investigate relationships between land use, farm waste management practices and river quality.
Water quality of small tributaries in this area is poor, and intensive chemical monitoring has shown that discharges from farmyards are a major source of pollution. Rainfall has been shown to exacerbate this effect either through field runoff or wastes washing directly from the farmyards. The status of benthic macroinvertebrate communities in these tributaries is poor and, typically, only a few pollution-tolerant species are present.
Small tributaries from farms appear to affect both the water chemistry and biology of larger watercourses, although this effect may be quite localized.
Future research will look at ways to reduce the impact of farm wastes on river quality. This will provide the basis for producing recommendations and guidelines for catchment management aimed at minimizing pollution of rivers from farming practices.     

The effects of a hazardous and a domestic waste landfill on the trace organic quality of chalk groundwater at a site in East Anglia

As part of a research project to assess the effects of landfill leachates on groundwater quality thirteen boreholes within, around and down groundwater gradient from two adjacent domestic and hazardous wastes sites were sampled for trace organic quality.Results so far show that significant inorganic and gross organic (TOC) groundwater contamination does not occur more than a few metres from the landfill boundaries. Trace organic analyses indicate that the mineral oils, phenolic wastes and chlorinated solvents, known to have been tipped into the hazardous waste landfill, have now reached the water table, although only at low concentrations.     

Some effects of stocking fish in waste treatment ponds

Oxidation ponds or sewage lagoons often present characteristics of natural water bodies in an extreme state of ecological imbalance. Excess nutrients of the decaying waste give rise to plankton blooms which subsequently die. In such conditions dissolved oxygen concentrations (DO) in the water are often low and the pH depressed. The addition of fish to ponds which twice a week received, per ha, wastes with a 5 day BOD of up to 800 kg (20°C) and 5600 kg solids, reduced plankton and benthic populations, increased the average DO, and raised the pH. All of these changes improve the effectiveness of a waste treatment pond for reducing BOD and removing nutrients from the water. Bacteria concentrations were as much as 15 times lower in treatment ponds stocked with fish as compared with unstocked ponds. Lower bacteria concentrations however reduced the rate of loss of COD in the solids of the waste.     

Significance of the soil in environmental quality improvement--a review

The broad outlines of plant and animal ecology are indicated and ecosystems are defined. The impact of agriculture and industry on these systems is indicated. The major forces bringing about instability of the soil are pointed out. Wind erosion, water erosion, nutrient and oxygen balances are described in principle. Intensification and specialization of agriculture are described in some detail. These intensive practices are compared to the older “normal” agriculture. Hence, the courses of the modern agricultural problems in environmental pollution and waste management are indicated. The magnitude of the pesticide problem is defined and the need for regulation is emphasized. Special consideration is given to chlorinated hydrocarbons and mercury compounds. The process of eutrophication is defined and is described as a natural process. Sources of artificial enrichment of the water are described as well as city and rural waste water.The remedial measures that need to be taken to maintain and/or improve the environment are discussed. Systems of handling animal wastes are described in some detail. Dry, slurry, and wet systems are described in regard to management. The control of excessive fertilizer nutrients, pesticides, and agricultural chemicals including heavy metals is outlined in some detail. Animal manure management as a part of the soil fertility system is described. Nitrogen and phosphorus management is discussed in some detail. Utilization of city waste water and sewage treatment plant sludges are indicated. Solid waste disposal on the land as a means of environmental improvement is considered from the point of view of disposing of raw sewage, sewage sludge, and solid wastes generally. Fruit and vegetable processing wastes can be treated by a process of overland flow in order to bring about adequate oxidation of these wastes. Wastes from packing plants for animal processing are much stronger wastes and require more complex treatment than fruit and vegetable processing wastes. Oil-spills as a pollutant on land are described in more or less quantitative terms. Remedial measures are given.     

利用废弃物制备白炭黑的研究现状及发展趋势

本文详细阐述了利用废弃物制备白炭黑的研究现状,重点介绍利用农业固体废物、矿山尾矿和工业废渣、废水等回收白炭黑,探讨了其发展趋势。     

Measurement of protein-like fluorescence in river and waste water using a handheld spectrophotometer

Protein-like fluorescence intensity in rivers increases with increasing anthropogenic DOM inputs from sewerage and farm wastes. Here, a portable luminescence spectrophotometer was used to investigate if this technology could be used to provide both field scientists with a rapid pollution monitoring tool and process control engineers with a portable waste water monitoring device, through the measurement of river and waste water tryptophan-like fluorescence from a range of rivers in NE England and from effluents from within two waste water treatment plants. The portable spectrophotometer determined that waste waters and sewerage effluents had the highest tryptophan-like fluorescence intensity, urban streams had an intermediate tryptophan-like fluorescence intensity, and the upstream river samples of good water quality the lowest tryptophan-like fluorescence intensity. Replicate samples demonstrated that fluorescence intensity is reproducible to +/- 20% for low fluorescence, 'clean' river water samples and +/- 5% for urban water and waste waters. Correlations between fluorescence measured by the portable spectrophotometer with a conventional bench machine were 0.91; (Spearman's rho, n = 143), demonstrating that the portable spectrophotometer does correlate with tryptophan-like fluorescence intensity measured using the bench spectrophotometer.     

A study conducted to reduce construction waste generation in Turkey

Waste occurs within the lifecycle of buildings, during the construction, modification and demolition phases. These construction wastes become serious environmental problems in many countries and in Turkey. However, no net data regarding the amount of construction wastes exist in Turkey. During its period of usage, frequent interior modifications are made for various reasons, particularly true for residences in Turkey, thus generating construction wastes. The primary environmental target regarding this subject should be the prevention and reduction of construction waste generation. The aim of this study is to provide suggestions regarding the prevention/reduction of waste generated due to modifications done for various purposes in residences in Turkey. To this end, a survey of homeowners in Istanbul was conducted to determine the nature and purpose of modification work done in residences. In order to come up with solutions towards reducing the construction waste generation, it is vital that these reasons are known. In light of the causes determined, suggestions for solving the problems have been developed.     

陶瓷废弃物代砂制备混凝土的强度特征

陶瓷废弃物经破碎筛分加工制成人工砂,以此作为混凝土的细骨料进行部分或全部取代天然砂,并对制备的混凝土不同龄期的抗压强度、抗折强度等特征进行了试验研究,研究中对不同取代率、灰水比、陶瓷砂处理方式、龄期等因素对陶瓷砂混凝土强度特征进行了系统考察.研究表明,陶瓷废弃物经破碎筛分加工后,可以满足混凝土用砂规范的要求,尤其是加工过程中与部分碎石混合破碎,其人工砂的性能是优异的.可全部取代优质河砂,而纯陶瓷废弃物加工的砂配制的混凝土,其立方体抗压强度和抗折强度值均能达到设计要求,甚至可以超过同等配合比的天然河砂配制的混凝土的强度;陶瓷砂混凝土的强度与天然骨料混凝土的变化规律相似,即随灰水比的增加而提高,随龄期的增长强度不断增加.强度特征的评价为陶瓷砂混凝土的配合比设计提供了有效的依据.     

Long-term safety analysis and model validation through URL research

In Germany, all types of radioactive wastes will be disposed of in deep geological repositories. While a repository for low-level radioactive waste (LLW) has recently been licensed, different host rock formations are considered for disposal of heat producing high-level waste (HLW). The latter includes directly disposed spent fuel (SF) and vitrified waste from its reprocessing. Different canisters and disposal concepts are considered for spent fuel disposal, i.e. thick-walled iron casks in horizontal drifts or thin-walled BSK3 steel casks in vertical boreholes. GRS is the leading expert institution in Germany concerning nuclear safety and waste management. For the recent 30 years, GRS has developed and continuously improves a set of computer codes, which allow assessing the performance and the long-term safety of repositories in various host rocks (salt, clay or granite) adopting different technical options. Advanced methods for deterministic as well as probabilistic assessments are available. To characterize the host rocks and backfill/buffer materials and to develop disposal technologies, comprehensive laboratory experiments and a large number of in-situ tests have been performed at GRS’ geo-laboratory and underground research laboratories in different host formations. Thermo-hydro-mechanico-chemical (THMC) processes occurring in the host rocks and engineered barrier systems are numerically simulated. The paper presents an overview of GRS’ work highlighting important results of performance assessment (PA) studies for both the salt and clay options. Also, recent results of in-situ investigations and laboratory studies are presented together with modeling results. Special emphasis is dedicated to the consideration of coupled THM processes which are of relevance in PA.     

Exergy analysis in the assessment of the sustainability of waste gas treatment systems.

This study focuses on the sustainability of different technological options for the treatment of waste gases from a waste water treatment plant loaded with volatile organic compounds. The options considered are biofiltration, active carbon adsorption and catalytic and thermal oxidation. The amount of resources and utilities to construct and operate each system have been investigated from the point of view of the Second Law of thermodynamics. The unit in which all resources are treated is Joules of exergy. It was concluded that biofiltration was the most exergetically efficient system. The cumulative exergy consumption of the resources and utilities for construction and operation have been quantified in exergy terms. Further on, the requirements for the abatement of emissions generated by operating the waste gas treatment systems and the amount of renewables have been taken into account in the assessment of the sustainability of the waste gas treatment technologies. Finally, a comparison between exergy analysis and life cycle analysis in assessing the sustainability of the waste gas treatment options, is presented.