Automotive shredder residue (ASR): reviewing its production from end-of-life vehicles (ELVs) and its recycling, energy or chemicals' valorisation

ASR is in Europe classified as hazardous waste. Both the stringent landfill legislation and the objectives/legislation related to ELV treatment of various countries, will limit current landfilling practice and impose an increased efficiency of the recovery and recycling of ELVs. The present paper situates ASR within the ELV context. Primary recovery techniques recycle up to 75% of the ELV components; the remaining 25% is called ASR. Characteristics of ASR and possible upgrading by secondary recovery techniques are reviewed. The latter techniques can produce a fuel- or fillergrade ASR, however with limitations as discussed. A further reduction of ASR to be disposed of calls upon (co-)incineration or the use of thermo-chemical processes, such as pyrolysis or gasification. The application in waste-to-energy plants, in cement kilns or in metallurgical processes is possible, with attention to the possible environmental impact: research into these impacts is discussed in detail. Pyrolysis and gasification are emerging technologies: although the sole use of ASR is debatable, its mixing with other waste streams is gradually being applied in commercial processes. The environmental impacts of the processes are acceptable, but more supporting data are needed and the advantage over (co-)incineration remains to be proven.     

Logistic model-based tool for policy-making towards sustainable waste management

The aim of this paper is to introduce a novel approach which supports facility planning in the field of waste management. Only 23 % of municipal solid waste (MSW) was thermally treated in the EU 27 in 2011. The increased exploitation of its potential for energy recovery must be accompanied by massive investments into highly efficient and reliable incineration technologies. Therefore, the challenge is to be efficient and use the technology to its optimal level. Feasibility studies of all plants providing a service for a region create a large and complex task. Gate fee (the charge for waste processing in the facility) represents one of the most crucial input parameters for the assessment. The gate fee is driven by configuration of the technology, competition, market development, environmental taxation and costs of waste transport to satisfy the plant’s capacity. Valid prediction of the gate fee thus presents a demanding task. In this paper, first, an advanced tool called NERUDA is introduced, which addresses logistic optimization and capacity sizing. The key idea is to focus on the problem of competition modelling among waste-to-energy plants, landfill sites, and mechanical–biological treatment plants producing refuse-derived fuel. Then, the main theoretical concepts are discussed, followed by the development of a suitable mathematical model. The goal is to obtain a minimized cost of MSW treatment for waste producers (municipalities). The application of the developed tool is demonstrated through a case study, where uncertain parameters entering the calculation are handled by a repetitive Monte Carlo simulation based on real-world data.     

Thermodynamic Analysis of the Gasification of Municipal Solid Waste

This work aims to understand the gasification performance of municipal solid waste (MSW) by means of thermodynamic analysis. Thermodynamic analysis is based on the assumption that the gasification reactions take place at the thermodynamic equilibrium condition, without regard to the reactor and process characteristics. First, model components of MSW including food, green wastes, paper, textiles, rubber, chlorine-free plastic, and polyvinyl chloride were chosen as the feedstock of a steam gasification process, with the steam temperature ranging from 973 K to 2273 K and the steam-to-MSW ratio (STMR) ranging from 1 to 5. It was found that the effect of the STMR on the gasification performance was almost the same as that of the steam temperature. All the differences among the seven types of MSW were caused by the variation of their compositions. Next, the gasification of actual MSW was analyzed using this thermodynamic equilibrium model. It was possible to count the inorganic components of actual MSW as silicon dioxide or aluminum oxide for the purpose of simplification, due to the fact that the inorganic components mainly affected the reactor temperature. A detailed comparison was made of the composition of the gaseous products obtained using steam, hydrogen, and air gasifying agents to provide basic knowledge regarding the appropriate choice of gasifying agent in MSW treatment upon demand.     

Effect of MSW source-classified collection on the emission of PCDDs/Fs and heavy metals from incineration in China

Municipal solid waste (MSW) source-classified collection represents a change in MSW management in China and other developing countries. Comparative experiments were performed to evaluate the effect of a newly established MSW source-classified collection system on the emission of PCDDs/Fs (polychlorinated dibenzo-p-dioxins and dibenzofurans) and heavy metals (HMs) from a full-scale incinerator in China. As a result of presorting and dewatering, the chlorine level, heavy metal and water content were lower, but heat value was higher in the source-classified MSW (classified MSW) as compared with the conventionally mixed collected MSW (mixed MSW). The generation of PCDDs/Fs in flue gas from the classified MSW incineration was 9.28 ng I-TEQ/Nm(3), only 69.4% of that from the mixed MSW incineration, and the final emission of PCDDs/Fs was only 0.12 ng I-TEQ/Nm(3), although activated carbon injection was reduced by 20%. The level of PCDDs/Fs in fly ash from the bag filter was 0.27 ng I-TEQ/g. These results indicated that the source-classified collection with pretreatment could improve the characteristics of MSW for incineration, and significantly decrease formation of PCDDs/Fs in MSW incineration. Furthermore, distributions of HMs such as Cd, Pb, Cu, Zn, Cr, As, Ni, Hg in bottom ash and fly ash were investigated to assess the need for treatment of residual ash.     

Towards cleaner technologies: emissions reduction, energy and waste minimisation, industrial implementation

This editorial introduces and provides an overview of a Special Issue dedicated to the jubilee 10th Conference of Process Integration, Modelling and Optimization for Energy Saving and Pollution Reduction—PRES’07. It contains thirteen selected papers covering various fields of cleaner technologies and environment policy problems. The technologies address recent developments in CO₂ capture in Combined Cycle power plants, CO₂ reduction in pulp and paper mills, process efficiency increases combined with energy savings at a mill, distillation separation enhancements and emissions control at gas plants, pre-combustion decarbonisation for polygenertion from fossil fuels, minimisation of CO₂ emissions in steam and power plants, a study of co-pyrolysis of biomass and plastic wastes, waste-to-energy system design (with a focus on incineration and gasification technologies), optimal design of wastewater treatment systems, and integrated production of sugar and biofuels from sugar beet. Among these topics, The Special Issue includes demonstration of the technologies in the form of Advanced Case studies.     

Characterization of air pollution control residues produced in a municipal solid waste incinerator in Portugal

This study is mainly related with the physical and chemical characterization of a solid waste, produced in a municipal solid waste (MSW) incineration process, which is usually referred as air pollution control (APC) residue. The moisture content, loss on ignition (LOI), particle size distribution, density, porosity, specific surface area and morphology were the physical properties addressed here. At the chemical level, total elemental content (TC), total availability (TA) and the leaching behaviour with compliance tests were determined, as well as the acid neutralization capacity (ANC). The main mineralogical crystalline phases were identified, and the thermal behaviour of the APC residues is also shown. The experimental work involves several techniques such as laser diffraction spectrometry, mercury porosimetry, helium pycnometry, gas adsorption, flame atomic absorption spectrometry (FAAS), ion chromatography, scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD) and simultaneous thermal analysis (STA). The results point out that the APC residues do not comply with regulations in force at the developed countries, and therefore the waste should be considered hazardous. Among the considered heavy metals, lead, zinc and chromium were identified as the most problematic ones, and their total elemental quantities are similar for several samples collected in an industrial plant at different times. Moreover, the high amount of soluble salts (NaCl, KCl, calcium compounds) may constitute a major problem and should be taken into account for all management strategies. The solubility in water is very high (more than 24% for a solid/liquid ratio of 10) and thus the possible utilizations of this residue are very limited, creating difficulties also in the ordinary treatments, such as in solidification/stabilization with binders.     

Evaluation of cleaner production audit in pharmaceutical production industry: case study of the pharmaceutical plant in Dalian,P. R. China

The pharmaceutical industry in China makes an important contribution to the national economy. However, the associated pollution problems cause gradual deterioration of the environment and impact adversely on the local community. Cleaner production (CP) technology, an effective way to reduce waste emission and save resources, has been widely employed in the pharmaceutical industry in the developed countries. Such technologies have been applied in a number of factories in China, although there is no integrated assessment and implementation procedure for implementing CP technologies in pharmaceutical plants. To solve such problems, a series of CP options are proposed and assessed here. CP is a powerful tool for decreasing waste production, limiting environmental pollution and natural resource depletion. Moreover, the return on investment in CP is quick, so it would seem that CP activities should be very much in demand by enterprises. Reality is less optimistic: frequently only limited interest is expressed, even after an explanation; business people hesitate to become actively involved. The processes in the pharmaceutical production industry produce a vast amount of waste, including wastewater with high concentrations of organic substances (the principal component), solid waste, and organic off-gas. To solve such problems, a series of CP options are proposed and assessed in this study. Having consideration to environmental impacts and economic efficiency, four groups of medium/high cost CP options were screened in an integrated assessment. To verify the proposed options, a case study was conducted in Degussa Luyuan, Northeast China. The characteristics of resource consumption and waste emission during the production process were identified. The proposed options were evaluated according to different aspects. An integrated CP system based on the proposed options was designed and then implemented in the factory. In three years of practical use, the productivity and quality of alcohol product were improved, with a reduction in waste and pollution and a marked increase in water/energy savings. This study provides theoretical and practical support for the extensive application of CP technologies and sustainable development in China’s pharmaceutical industry. These methods include ways to clean up production that are incorporated in the process design, reforming present production technologies, updating the equipment, exploiting new producing flowcharts, using cleaner energy, building recycling into the manufacturing process, recycling waste, enhancing management, developing environmental protection technology, and ensuring satisfactory end-of-pipe disposal.     

Indicators of sustainability: assessing the suitability of a foreign technology for a developing economy

Some of the primary objectives for importing foreign technology into developing economies are to provide essential amenities like potable water, stable electrical supply, and functional communication and health facilities. It is also aimed at improving the industrial development bases in order to achieve technological advancement. However, historical trends bear witness to the fact that a majority of these efforts by the governments of developing countries have failed because such technologies are not sustainable. This paper identifies a number of indices that decision makers can use to assess the suitability of a foreign technology being considered for import into the local economy and its likely sustainability over the long term. By identifying and examining sustainability factors in relation to the socio-political contexts of a specific culture and its techno-economic level of development, and by considering such factors in the decision-making process, the selection of appropriate technologies can be greatly enhanced and the enormous waste of economic resources can be avoided.     

The Efficiency of Different Technologies for the Preparation and Use of Wet Fuel in Power Engineering

We consider the possible technical solutions for the treatment moisture fuel from the standpoint of such general problems as a reduction in greenhouse gas emissions and lowering fuel costs with increased energy generation. The use of the biofuels, which is almost always highly wet, does solve these problems in perspective, but it results in an urgent problem regarding an increase of the energy efficiency of the suitable technologies. The practice shows that a reduction in the costs of fuel and energy production currently takes place with generation based on the cheap brown coal (lignite); however, it is necessary to increase qualitatively the efficiency of power plants in order to reduce fuel consumption, as well as atmospheric emissions. We consider the use of complex technologies of moisture fuel preparation for its efficient application via intensive drying with subsequent gasification in order to pass to the combined cycles with the gas turbines. A new technology for intensive energy-saving drying using superheated pressurized steam is presented. We present an analysis and comparison of the means of such approach to implementation and substantiate the selection of the optimal solutions, which are applicable not only to power engineering but also elsewhere in the utilization of moisture combustible materials and waste products.     

Demonstration plasma gasification/vitrification system for effective hazardous waste treatment

Plasma gasification/vitrification is a technologically advanced and environmentally friendly method of disposing of waste, converting it to commercially usable by-products. This process is a drastic non-incineration thermal process, which uses extremely high temperatures in an oxygen-starved environment to completely decompose input waste material into very simple molecules. The intense and versatile heat generation capabilities of plasma technology enable a plasma gasification/vitrification facility to treat a large number of waste streams in a safe and reliable manner. The by-products of the process are a combustible gas and an inert slag. Plasma gasification consistently exhibits much lower environmental levels for both air emissions and slag leachate toxicity than other thermal technologies. In the framework of a LIFE-Environment project, financed by Directorate General Environment and Viotia Prefecture in Greece, a pilot plasma gasification/vitrification system was designed, constructed and installed in Viotia Region in order to examine the efficiency of this innovative technology in treating industrial hazardous waste. The pilot plant, which was designed to treat up to 50kg waste/h, has two main sections: (i) the furnace and its related equipment and (ii) the off-gas treatment system, including the secondary combustion chamber, quench and scrubber.     

Waste to energy: the new frontier?

Each year the South East of England, including London, generates some 27.5 million tonnes of municipal, industrial and construction wastes. With a few exceptions this waste is disposed of at landfills, often some distance from the origin of the waste. However these landfills are nearing completion and, because of planning and environmental constraints, are not being replaced at a rate sufficient to guarantee demand is met. Indeed it is now recognised that by the turn of the century a substantial shortfall in landfill capacity will exist. It is against this backcloth that several companies have sought to develop waste-to-energy plants. This paper, using a proposed plant at Belvedere as an example, looks at the waste-to-energy solution in the context of the evolving disposal crisis. It reviews the role it can play and considers whether this well proven technology truly represents a new frontier for waste management in the UK     

Best management practices for corporate, academic and governmental transfer of sustainable technologies to developing countries

Innovations with respect to technologies that contribute to environmental sustainability have emerged within national government laboratories, international agencies and within academic research institutes. Since each of these entities is understandably more focused on ab initio research, conceptual development and proofs of concept, the production level manufacturing and broad dissemination of such technologies require development of best management practices (BMPs) for effective partnerships with and/or technology licensure to private sector industry. Alternatively, certain technologies that address specific environmental sustainability needs within the developing countries can be and have been transferred directly, either through bi-lateral transfers or through multi-lateral agencies, serving as intermediaries. The appropriateness of such transfers is contingent upon host country environmental, cultural and socio-political conditions, the type of technology involved, the “terms of transfer” and the relationships established between the technology conceivers and the end-users. The authors select examples of identified modes of sustainable technology transmission and derive experiential BMPs, which may be of some utility for future sustainable technology transfer. Moreover, in providing these BMPs, the historical record and contemporary caveats with respect to unregulated technology transfer, whether sustainable or otherwise, to developing countries and the array of corresponding proposed codes of conduct are examined, given the normative objective that such technologies should ultimately contribute to ecologically benign and societally beneficial objectives, such as environmental sustainability, equitable growth and poverty alleviation. These issues and the need to establish BMPs would be broadly relevant with the new focus on climate change-related technology funds and associated regional impact projects evolving across the globe and within the developing countries in particular.     

国内外生活垃圾焚烧发电技术进展

随着人们对环境方面要求的日益增长,垃圾合理处理在践行绿色发展理念和推动生态文明建设进程中发挥着越来越重要的作用。生活垃圾焚烧发电技术作为固废资源利用的一种方法,如今已经演变成为一种成熟的资源利用技术。分别从垃圾焚烧发电行业的上、中、下游,即从垃圾焚烧的原料性质、燃烧发电技术以及烟气控制方面对国内外生活垃圾焚烧技术进行了比较分析,认为随着生活垃圾量日益增长,生活垃圾焚烧技术仍是一种实现减量化、资源化必不可少的手段,但是需要提升焚烧技术,改进国产焚烧工艺,严格控制焚烧烟气中污染物的排放,建立实时监测点,避免造成二次污染。     

Gas-Producer Technologies of Organic-Waste Processing

The technologies of gasification of combustible organic waste are considered. The characteristics of the processes of gasification of vegetable biomass waste in the gas producers of direct and inverse combustion processes are given. __________ Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 78, No. 4, pp. 63–67, July–August, 2005.     

Comparative risk assessment: an international comparison of methodologies and results

Comparative risk assessment (CRA) is a systematic procedure for evaluating the environmental problems affecting a geographic area. This paper looks beyond the U.S. border and examines the experience with CRAs conducted in various developing countries and economies in transition, including Bangkok, Thailand, Cairo, Egypt and Quito, Ecuador, as well as other locations in Eastern Europe, Asia and Central and South America. A recent pilot CRA conducted in Taiwan is also considered. Comparisons are made of both the methodologies and the results across the relatively diverse international literature. The most robust finding is that conventional air pollutants (e.g., particulate matter and lead) consistently rank as high health risks across all of the CRAs examined. Given the varied nature of the settings studied in the CRAs, including level of economic development, urban-rural differences, and climate, this finding is particularly significant. Problems involving drinking water are also ranked as a high or medium health risk in almost all the countries studied. This is consistent with the results of analyses conducted by the World Bank suggesting contamination, limited coverage and erratic service by water supply systems.Beyond the major air pollutants and drinking water, the CRA results diverge significantly across countries. A number of problems involving toxic chemicals, e. g., hazardous air pollutants, rank as high health risks in the US but do not appear as consistent areas of concerns in the other countries studied. This likely reflects the so-called "risk transition" - the shift from sanitation and infection disease problems to those involving industry, vehicles and toxic substances - that often occurs with economic development. It may also reflect the greater information about sources of toxic pollutants in the U.S. For other problems, there are important differences across the developing countries and economies in transition. For example, hazardous and (industrial) non-hazardous waste issues ranked as medium or low health risks in all the countries studied, except for Taiwan where unmanaged toxic waste sites were considered to pose high risks. While the generally low ranking is consistent with the notion that few people are directly exposed to hazardous and (industrial) non-hazardous waste, it is not entirely surprising that views might be different in Taiwan, where space is so limited and population density is so high.We suggest that the wide range of findings likely reflect genuine differences among the countries studied. However, we cannot entirely rule out the possibility that some of the observed similarities (and differences) arise from the (relatively) common methodologies employed.     

Persistent pollutants emission abatement in waste-to-energy systems

The paper is focused on analyzing methods, which enable a substantial reduction of persistent organic pollutants (POP) emissions to meet the environmental limits. Technologies based on adsorption of harmful compounds using activated carbon, technologies DeNOx/DeDiox as well as technology of catalytic filtration using a special material REMEDIA D/F are considered and compared. The latter technology consists in using a bag-house with bags manufactured from a special material (two layers—membrane from expanded PTFE and felt with bound in catalyst) called REMEDIA, which has successfully been used for the removal of PCDD/F during recent period. An optimum design is based on the computational support concerning the bag-house. It is illustrated through an industrial application of the municipal solid waste (MSW) incinerator with capacity of 15 t/h (96.000 t/year) of waste treated which is operated as a waste-to-energy system. Based on the experience from operating this incineration plant it has been proved that even after more than 3 years operation the activity of filtration material was not decreased and efficiency of dioxins removal from flue gas ranges from 97 to 99%. These facts come from complex measurements where concentration of PCDD/F toxic congeners in both flue gas and separated flying ash was measured. We arrived at confirming expected assumptions that various congeners are not decomposed uniformly in the dioxin filter and the stage of their decomposition depends on their representation in the gas phase. It is strongly influenced by their molecular weight. Their results and experience contribute to further improving the system.     

Effect of physicochemical properties of coal gasification fine ash on its wettability

Coal gasification, recognized as one of the most effective coal utilization technologies, will produce a certain amount of fine ash during the high-temperature reaction process. The wettability of gasification fine ash is a critical parameter to characterize the degree of high-temperature reaction and determine the separation efficiency of purification process. In the present work, the effect of physicochemical properties on the wetting behavior of different gasification fine ash is studied. The difference in wettability between particle size and types can be explained by the unique properties of particles (i.e. pore structure, mineral composition, and chemical structure). The results show that with the decrease in particle size, the surface morphology transforms from an irregular shape with a rough surface to a spherical shape with a smooth surface. The pore structure, characterized by fractal surface dimension D_s, presents positive correlations with the contact angle for a single type of fine ash. The mineral composition can just qualitatively assess the hydrophilicity of particles. Only the ratio of hydrophilic chemical structure can be used as a generic parameter to describe the wetting performance. Meanwhile, the wettability of hydrophilic particles can be enhanced by increasing moisture content, but there is no significant effect of moisture content on the wettability of hydrophobic particles.     

A Roadmap for Humidity and Moisture Measurement

An initial roadmap for humidity and related measurements was developed in Spring 2006 as part of the EUROMET iMERA activity toward increasing impact from national investment in European metrology R&;D. The conclusions address both humidity (for which standards and traceability methodologies exist, but need to be developed) and moisture content of materials (for which measurement traceability is more problematic and is not so well developed in general). The roadmap represents a shared vision of how humidity and moisture measurements and standards should develop over the next 15 years to meet future needs, open to revision as needs and technologies evolve. The roadmap identifies the main social and economic triggers that drive developments in humidity and moisture measurements and standards—notably, global warming and advanced manufacturing processes. Stemming from these triggers, key targets that require improved humidity and moisture measurements are identified. In view of global warming, one key target is the development of improved models of climate through improved measurements of atmospheric water vapor. A further target is the reduction of carbon emissions through humidity measurement to optimize industrial heat treatment and combustion processes, and through humidity and moisture measurements to achieve energy-efficient buildings. For high-performance manufacturing, one key target is improved precision control of manufacturing processes through better humidity and moisture measurements. Another key target is contaminant-free manufacture in industries such as microelectronics, through high-purity gases of known moisture content at the parts-per-trillion level. To enable these outcomes, the roadmap identifies the advances needed in measurement standards. These include the following: improved trace humidity standards; new humidity standards to cover high temperatures and pressures, steam, and non-air gases; and improved standards for moisture content of materials. Technologies that are likely to be harnessed are also identified, such as emerging laboratory techniques, existing and new research-grade hygrometers, hygro-thermal modeling, and nanotechnology.     

Use of waste materials in the construction industry

A Symposium by Correspondence has been organised on behalf of RILEM on the use of waste materials and industrial by-products in the construction industry. 18 countries (excluding the UK for which the authors are providing information) submitted contributions and in this paper these contributions are summarised and analysed. Information about individual materials has been extracted from the national contributions and a chapter devoted to each waste in turn. The properties, occurrence, present uses and possible future applications of each waste are described. Blastfurnace slags and pulverised fuel ashes are the two materials which are being used to the greatest extent. Blastfurnace slags are used overall to some 80% of their production and in several countries virtually all that is produced is used and the slags are regarded as a highly satisfactory material. Pulverised fuel ashes are about 20% used overall but up to 70% is used in some countries. Much of these two materials is used as fill but many more sophisticated uses are developing. These materials can make a particular contribution in conserving energy in the manufacture of cementitious materials and of lightweight aggregates. Overall however the proportion of mineral wastes which is used is only about 5% of the production and most is used in relatively low grade applications such as fill in roads and embankments. The most influential factor in determining whether or not a waste material or by-product is used is the economic cost in comparison with the alternative natural material in a particular application. These costs are primarily made up by handling, processing and transport but the social benefits of using a waste, for example avoiding the dereliction associated with the tipping of a waste material or the quarrying of a natural, should not be forgotten. Possible disbenefits such as pollution arising during processing or a less well proven technical performance should also be taken into account. Adequate knowledge of the properties of the waste materials and products containing them are therefore essential to enable a balanced judgement to be made on the overall advisability of using a waste material in a particular situation.     

Modern and appropriate technologies for the reduction of gaseous pollutants and their effects on the environment

Harmful effects on environment such as global warming and climate change may result from the gases emanating from fossil fuel combustion. Jordan and most Middle East countries use fossil fuels exclusively. Therefore, new technologies which could accommodate the demand for cleaner effluents, such as: combined cycles, fluidized bed combustion, magneto hydrodynamics, fuel cells, nuclear power, natural gas, renewable energy, and energy conservation have been considered. CO₂ being the most produced gas, many technical methods of reducing and reusing CO₂ have been suggested such as: Injection in oceans, storage in caverns, injection in depleted oil and gas fields, pumping during oil recovery, storage as CO₂ ice, elimination by fixation using water algae, and increasing plantation especially forestation. These methods are being used at different degrees in the Middle East countries. Reduction of formation and harmful effects of other gaseous pollutants is also discussed, with some concentration on the transportation sector, energy efficiency and fuel cells, which have special importance for the developing countries.