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The brisk escalation in population, energy demand and waste production are the pivotal dilemma confronted world wide. Thus, gasification could be considered as a favorable, economical and ecofriend...

In recent years, Yokohama City, Japan, has seen substantial efforts to address socio-environmental issues. One such effort is the G-30 program, which has helped reduce garbage waste production by 4...

Waste production is associated with human inhabitation and its rate is increasing over time. Globally, the major proportion of waste is disposed of through landfilling and open dumping, which is en...

Large-scale mining methods are commonplace in the mining industry, and caving has become the preferred underground mining technique. The use of block caving has increased worldwide and is expected to grow because of high production rates, low mining costs, and low waste production. One key engineering consideration in block caving is the drawpoint spacing layout, which must be selected prior to production based on widely spaced exploration data; uncertainty is highest during this stage of mining; and selecting an appropriate extraction level and layout is important for economic and safety considerations. In the proposed methodology, uncertainty in the grade block model is assessed with sequential Gaussian simulation and an optimisation procedure is developed to maximise net present value over many realisations while being constrained by mining considerations. This novel approach generates one layout that is optimal over all realisations rather than consider optimisation on a single kriged model wh...

The next generation nuclear facilities like Gen-IV fission reactors and fusion plasma will have a huge amount of activated waste production and resulting harmful consequences in terms of radioactive responses such as activity, decay heat, and dose. It is imperative to understand and quantify the impact of individual parent elements or isotopes in the material on major radiological responses. Such quantification serves as an impact indicator. This paper attempts to develop a method to aid this quantification that would eventually offer a complete material activation analysis. Here, we begin by presenting the mathematical formulation to account for the contribution of the parent constituents of any irradiated material toward the radiological responses directly, defined as the contributing factor (CF). The method is easily adaptable to other activation solvers and provides the user with CFs of parents that highlight the individual importance of the constituents. These factors can be used to determine...

The immobilization of multi-enzyme systems on advanced materials is an emerging technology inspired by the spatial localization found in Nature. These systems harness the high chemo-, regio- and stereoselectivity of the enzymes and the heterogeneous nature of the resulting biocatalyst. This synergy allows more efficient and selective synthetic schemes which reduce waste production and simplify downstream processing. The revolution of the nanotechnology has contributed to design advanced materials that allow precisely controlling the spatial distribution of the different catalytic modules forming a multi-enzyme system. Outstandingly, this fact has boosted the development and the improvement of more complex cascade reactions catalyzed in vitro by heterogeneous multi-functional biocatalysts. In this review, we have discussed the different challenges that must be faced during the immobilization of multi-enzyme systems; from the carrier surface to the incorporation of cofactors into the solid-phase. We...

Studies on the utilization of forest and agricultural wastes are of the extreme significance in any country where there exists a gap between the availability of, and the requirements for, livestock feeds. Forest and agriculture wastes have big potential for energetic valorization. The energetic value of these wastes in Europe is 4.5 × 1012 MJ/y. Forest wastes are nowadays utilized as feedstock for integrated gasification processes. Therefore, there is remarkable underutilization of agricultural wastes. While waste production in the industrial sectors is usually reducing, the propensity of waste production from municipalities appears to be opposite.

This article focuses on analytical models of two-machine one-buffer Markov lines including waste production. The aim is to compute the probability of producing good parts, referred to as effective efficiency, when waste production is related to stoppages of the first machine. This problem is common in industrial fields where parts are generated by a continuous process; e.g., in high-speed beverage packaging lines. Two innovative models including waste production are presented: the WP-Basic Model extends the model of a basic two-machine–one-buffer transfer line; the WP-RP Model extends the model of a two-machine–one-buffer transfer line with a restart policy operating on the first machine (i.e., when the first machine is blocked because the buffer is filled, it is not allowed to resume production until the buffer becomes empty). The two existing models are improved by distinguishing, at any time step the first machine is operational, whether it is producing a good or a bad part. The probabilities of the sy...

High population growth and immigration rate from rural areas to urban centers have led to increased waste production and numerous urban landfill sites in different parts of Iran during the past three decades. The present study was carried out in southwest Iran where the aforementioned factors have occurred at an extremely high rate. There are four cities in this part of the country with a population of about 2.250 million and three landfill centers are located near these cities. The main aim of the present study was to estimate the CH4 and total GHGs emission rate from the mentioned sites. So, the components of urban solid wastes and the share of wet waste were determined in the areas of study. The results revealed that the share of wet solids was between 65 and 73%. Also, methane and total GHGs emission in landfill sites were estimated at about 2244.7 tons/year and 8405 tons/year during 2010, respectively. Moreover, the amounts of CH4 and total GHGs emission for the next 75 years, respectively, are estim...

The increasing demand of faster, less expensive, easier, and more environmentally-friendly methods has favored the miniaturization of systems for sample preparation. These new procedures have led to lower reagent and materials consumption and waste production. One extraction technique recently introduced is based on the use of hollow fibers as support to liquid membranes which enables the extraction with solvents of a different nature from a donor external phase to an acceptor phase inside the lumen of the fiber. This is an up-to-date comprehensive review on the analytical applications of hollow fiber liquid phase microextraction (HF-LPME) that includes two and three-phase configurations, carried-mediated extraction and electromembrane extraction. A brief review on the basic extraction principles for these techniques, describing and discussing the different operation and configuration modes, has been carried out. Supplementary materials are available for this article. Go to the publisher's online edition ...

Energy improvement measures can destroy the historical and architectural values of existing buildings. From a broader environmental perspective, extensive energy efficiency measures may even lead to increased greenhouse gas emissions from demolition, waste production and transportation of new materials. The complexity of the consequences of energy-saving measures on existing buildings calls for more holistic methods in discussing solutions. This paper presents an integrated analysis method developed by three masters' students at the Norwegian University of Science and Technology. The method examined different short- and long-term impacts from various energy efficiency measures on a model building by combining life cycle assessment, energy calculations and a self-developed heritage value assessment system. By combining the results from the different analyses in an integrated decision-making tool, it was possible to discuss optimal solutions for energy improvement, taking both environmental and heri...

The hazardous waste management (HWM) practice at Tehran University of Medical Sciences Central Campus, Iran, was investigated in this study. Four schools were selected and the required information such as type and amount of wastes, temporary storage methods, waste discharge frequency, and final waste disposal methods using sampling, questionnaires, interviews with laboratory staff, and reference to available documents were gathered. The quantity of hazardous waste generation per year excluding the uncontrolled wastewater was found to be 2.072 tons per year. The obtained results show that wastes having features of being infectious, toxic, ignitable, carcinogenic, corrosive, and reactive were present at 32%, 28%, 16%, 14%, 8%, and 2%, respectively. In the central campus, hazardous solid wastes managed with household solid wastes and hazardous liquid waste were discharged into the sinks without any kind of control; improper HWM practices are evident from the point of waste production to final disposal.

This paper reports the development of a carbon dioxide emissions matrix for the Oeiras municipality, one of the largest Portuguese municipalities, located in the metropolitan area of Lisbon. This matrix takes into account greenhouse gas emissions, caused by an increase of electricity demand in buildings as well as solid and liquid wastes treatment, from the domestic and services sectors. Using emission factors that were calculated from the relationship between the produced energy and amount of treated wastes, greenhouse gas emissions in the Oeiras municipality, were estimated for a time series of six years (1998 to 2003). The results obtained showed that the electricity sector accounts for about 75% of the municipal emissions in 2003. This study constitutes a tool to define sectors for appropriate action, including energy planning and also public information.

During the last decade waste management has become one of the most problematic and demanding issues to be addressed in Ireland. Increasing waste production and landfills reaching their capacity are placing unprecedented pressure on the land, and are unsustainable in the long term. However, while surveys of public opinion present a picture of a population increasingly concerned about the quality of the environment and the problem of waste management, there has been an increase in amounts of municipal waste being sent to landfill. Although not unique to Ireland, this gap between values and actions is one that deserves further critical consideration if positive sustainable waste management strategies are to be developed. This paper, based on research being conducted in two case study locations in the west of Ireland, engages with value–action gaps in terms of waste management strategies in Ireland. Based on empirical evidence the paper examines the public's self-reported barriers to more sustainable...

Using mainly qualitative data from a four country case study, this paper describes the nature of home-based enterprises (HBEs) and the wastes that they produce. It finds that most only generate material similar to domestic wastes, but in greater quantities. While some are undoubtedly generating dangerous wastes, they are only a small proportion of all HBEs and tend to be aware of at least some of the problem and take mitigating steps. The paper argues that the encouragement of clean processes should replace the usual negative views about HBEs that are held by policy makers.

The issue of waste management within airports is becoming increasingly important with enormous increases in passenger numbers and is a key responsibility of the facilities manager. Airports are notoriously poor environmental performers and this growth in the industry is leading to increasing levels of waste production. The purpose of this paper is to assess the efficiency of waste management operations at BAA airports, with reference to best practices within airports in continental Europe. The paper presents the findings of a survey of waste management methods in a sample of UK airports. The analysis of numerical data is based on those airports in the BAA group. Many of these are among the busiest airports in Britain, and Heathrow and Gatwick are two of the world's busiest. Data constraints prevented a more detailed analysis of other airports outside BAA. The paper highlights some difficulties in measuring BAA's waste management efficiency based on the waste hierarchy and concludes that some European airp...

Even in the phase of maturity reached by nuclear industry, the industrial needs for nuclear data are numerous.For present plants, improving competitiveness, satisfying increasingly stringent safety requirements, increasing the fuel burnup, facing the ageing of plants, designing compact interim storage, reprocessing, etc. are sources of many needs for new or improved data.For the middle term, replacing the present industrial facilities may include some innovations, mature for industrialisation, like HTRs or inert matrix fuel in LWRs. Using new materials, aiming at ultra high burnups, burning different types of fuel (e.g. thorium cycle), induces new data requirements.For the long term, other innovative technologies must be available, for keeping the fast reactor option open, transmuting wastes, minimising waste production in integrated fuel cycles (e.g. with molten salt reactors), increasing the coolant temperature (> 900°C), etc. For such options, only the data needed for answering key feasibility issues a...

The ferro‐alloy industry in South Africa can be divided into two groups of processes, the first concerned with the mining and initial beneficiation of ores and the second with the production of various metallic products, ranging from pig iron to various ferro‐alloys and stainless steel. Waste production from these processes is considerable, with the majority of waste products in the form of solids, such as furnace slags, emission control dusts, flotation tailings and leach residues. Traditionally, these waste materials have been disposed of to landfill, usually in the form of large‐scale heaps or dams. It is only since recently that the management of ferro‐alloy wastes is starting to be governed by concerns about the long‐term environmental stability of such deposits, which is associated with the potential leachability of salts and heavy metal species contained therein. The concept of Clean Technology is beginning to influence process design options in the sector with the ultimate aim to reduce t...

Imposing environmental taxation on external costs of energy will not only affect the environmental impact of the energy sector itself, but it will tend to decrease environmental damage from other sectors of the economy as well. We have assessed the effects of a shift of taxation from taxing labour to taxation of external costs caused in the energy sector. Several examples give results compatible with the hypothesis that the changing price relation between labour and energy resulting from such a tax shift will make re-use, repairs and recycling increasingly competitive and thus tend to decrease mining as well as waste production. Likewise, less energy-intensive commodities and services in general would become increasingly competitive, and would tend to decrease the environmental load further. These environmentally desirable effects are beyond the taxed external effects of the energy sector itself and occur as an indirect effect of the increased relative price of energy.

A new methodolgy based on a generic pollution balance equation, has been developed for minimizing waste production in manufacturing processes. A "pollution index," defined as the mass of waste produced per unit mass of a product, has been introduced to provide a quantitative measure of waste generation in a process. A waste reduction algorithm also has been developed from the pollution balance equation. This paper explains this methodology and demonstrates the applicability of the method by a case study.

RIM+ is a Dutch acronym for Environmental Information and Planning Model (Reken‐ en Informatie‐systeem Milieuhygiene). It is currently under development at the National Institute for Public Health and Environmental Protection in the Netherlands. The objective is to generate projections of emissions, waste production and energy use (environmental load) for any pollutant, waste material or energy carrier. Also financial implications of environmental policies can be calculated. All these projections will be calculated using the same principle: the process method. By estimating the future development of processes and applying measures to reduce environmental load, the users of RIM+ will be able to generate these projections. The structure of RIM+ is strongly modular and some modules will be built in 1992, others in 1993.

The disposal of radioactive wastes by launching them into space will require extensive treatment and preparation on the ground in order to convert these wastes into suitable payloads. If a particular radioactive element is to be managed by space disposal, then it will have to be separated from the wastes, concentrated, and converted into a suitable disposal form for launch. In many cases, this waste management approach will result in the construction and operation of highly complex and expensive radiochemical plants for treating many fuel cycle wastes and producing the necessary payloads. In addition, secondary wastes will usually result from the chemical processing steps that are required to produce these payloads. Also, some of the payloads that appear most attractive for space disposal with respect to launch requirements cause significant problems with respect to ground processing. Therefore, the decision to produce any particular payload for disposal must consider all of the ramifications for the ground processing systems as well as the launch vehicle. Preliminary evaluations of some of the projected impacts on ground systems, such as secondary waste production and radiochemical processing requirements, are presented for iodine, /sup 14/C, technetium, strontium, cesium, and actinide/lanthanide payloads that result from processing lightmore » water reactor fuel cycle wastes.« less

The scandal in summer 1988 of the 'homeless' toxic waste ship, the Karin-B, only scratched the surface of a problem much deeper than was portrayed by the media (which suggested that a few rogue dealers were out for quick profits before better regulation excluded them). However, international trading in wastes has rapidly grown into a huge, diverse and complicated business, which makes it almost impossible to document and control the multifarious agents, consignments and deals involved. A monitoring effort organised by Greenpeace identified more than 3.6 million tons of waste shipments from industrialised to underdeveloped countries between 1986 and 1988 alone.1 As an indication of the further pressure for export, over 17.4 million tons per yearapproaching the officially accepted figure for the total volume of toxic industrial wastes produced in the European Economic Community -have been proposed for shipment to developing countries, but then refused permission. These figures almost certainly underestimate the full picture. Hundreds of waste brokers, producers and shippers of varying levels of professionalism are trying to find disposal outlets for the ever-growing volumes of industrial country wastes. Tighter local environmental standards mean that these are more and more difficult (and expensive) to treat and dispose of in their country of origin. Despite these escalating disposal difficulties in industrial countries, the volumes of wastes produced continue to rise. Export to Third World countries seems to undermine the ability of tighter local disposal standards to force the reduction of harmful waste production in the first place. Provoked by the intense efforts to export industrial society waste to their countries, forty developing countries have officially banned waste imports in the last two years, and yet more have rejected specific offers,2

There has been considerable controversy concerning the alpha waste and the proliferation hazards of breeder reactors and chemical reprocessing. To evaluate the waste and proliferation hazards of different fuel cycles, both with and without reprocessing, calculations are made of the production of actinides by different fuel cycles, both with and without fuel and waste actinide recycle. 13 refs.