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Agriculture and forestry (including land use changes) contribute approximately 30% of anthropogenic greenhouse gas (GHG) emissions globally, but have a significant mitigation potential. Several activities to reduce GHGs at a landscape scale are under development (e.g. Reducing Emissions from Deforestation and forest Degradation activities or Clean Development Mechanism projects) but these will not be effective without improvements at the basic management scale: the farm. A number of farm-level GHG calculators have been developed; to increase farmers awareness of the GHG impacts of their management practices; to aid decision-support for mitigation actions; and to enable farmers to calculate and communicate their GHG emissions, whether for their own records, as a prerequisite to supply chain certification, or as part of larger scale mechanisms. This paper compares three farm-level GHG calculators with significant potential influence. It demonstrates how the tools differ in output when using the same input data and highlights in detail what lies behind these differences. It then discusses more generally some potential implications of using different calculators and the important considerations that must be made, thus helping future tool users or developers to interpret results and better achieve consistent and comparable results.

The number of private and voluntary agri-food standards, or certification schemes, has boomed in recent years. Their proliferation and prominence has been fuelled, in part, through wide-scale adoption by agri-food supply chain actors using them to display environmental credentials and to signify that products have been ‘sustainably sourced’. As both a source of greenhouse gas (GHG) emissions and a sector with significant mitigation potential, agriculture has faced increasing pressures to demonstrate GHG emission reductions; it is therefore important to understand whether and how GHGs are addressed within certification schemes. This paper reviews a number of well-known and widely applied certification schemes in the agri-food arena, focussing on several of the certification schemes employed by Unilever and other multi-national companies as part of their commitment to reduce their GHG footprint and source their agricultural raw materials sustainably. A framework is constructed to enable comparison of schemes to elucidate the differences in the range of GHG drivers considered, the type of intervention in which they are addressed and how strictly the GHG relevant requirements are imposed. This should be useful for companies who are embarking on GHG reduction activities and are using agri-food certification schemes as a mechanism to do so.

Most interpretations of sustainable development recognise that there are constraints on long-term human activities imposed by material and energy availability and by the capacity of the planet to accommodate wastes and emissions; inter- and intra-generational equity within these constraints is then an ethical principle underlying sustainability. This leads to identifying three dimensions of sustainable development: techno-economic, ecological and social. This paper reviews the development of indicators to reflect these three dimensions, applicable to industrial sectors, companies and broad groups of products or services. Indicators of environmental and economic performance are relatively well established. They can be combined to indicate the sustainability of products, services and supply chains. Indicators of social performance are more problematic, particularly indicators to describe the social value of products and services. Cases from the process, petroleum and petrochemicals, electronics and fast moving consumer goods sectors are reviewed, showing that social indicators must be developed through public participation.

To achieve more than incremental reductions in resource consumption and waste, it will be necessary to develop new approaches to the systematic use and re-use of materials in the kind of system termed an "industrial ecology". This paper presents a new methodology--CHAin Management of Materials and Products (CHAMP)--developed for modelling the flow of materials through a succession of uses with different performance requirements. Although developed specifically for polymers, the CHAMP approach is also applicable to other materials and products. Materials are characterised by a set of technical performance parameters, termed utilities. Geographical location is also treated as a utility to enable logistics--both distribution of products and collection of used products or waste--to be incorporated within the same modelling framework. Processing, transport and use are treated as activities through which a material can pass. The costs and environmental impacts of activities are included in the modelling framework, and are assessed on a life cycle basis by considering the complete supply chain of materials and energy used by each activity. The methodology includes acceptance criteria which determine whether a material is suitable for specific uses or activities. These criteria are applied within the model to guide selection of materials for specific applications and of successive uses for specific materials. A simple example of the CHAMP approach is given, to illustrate the kinds of problem to which it has been applied.

ISO 14041 requires that allocation by physical causality must reflect the quantitative changes in product outputs or functions and will not necessarily be in proportion to simple physical measure such as mass. This paper examines the instances where physical causality can be represented by mass. However, it also goes further than ISO to demonstrate that the type of causality in the system is not necessarily always the same and can change depending on the way the system is operated. Whole system modelling and the marginal allocation approach are used to identify the correct type of causality for different operating states of the system and the corresponding changes in the environmental burdens. This is generally not possible with the other allocation methods, also examined in this paper. Both process- and product-related burdens are considered and the approach is illustrated by a reference to an existing system producing five boron co-products

This paper uses an industrial case study of a boron system producing five co-products to examine different allocation methods recommended by ISO 14041 and compare them with the allocation methods most commonly used by LCA practitioners. In particular, allocation by physical causality is discussed. The paper illustrates how the use of whole system modelling can help to identify the correct type of causality for allocation. The case examined here concerns marginal changes of product-related parameters in the system, in this case represented by the output of boron co-products. The analysis shows that in some cases it can he correct to allocate the burdens on the basis of a simple physical quantity, such as mass, as long as the allocation parameter is based on physical causation and is not chosen arbitrarily. In whole system modelling, the correct causality is identified by the model itself, so that the possibility of allocation by an arbitrary parameter is avoided. However, as for system disaggregation and expansion, allocation through mathematical modelling may only be possible if detailed data for the system are available.

Linear Programming (LP) is a powerful mathematical technique that can be used as a tool in Life Cycle Assessment (LCA). In the Inventory and Impact Assessment phases, in addition to calculating the environmental impacts and burdens, it can be used for solving the problem of allocation in multiple-output systems. In the Improvement Assessment phase, it provides a systematic approach to identifying possibilities for system improvements by optimising the system on different environmental objective functions, defined as burdens or impacts. Ultimately, if the environmental impacts are aggregated to a single environmental impact function in the Valuation phase, LP optimisation can identify the overall environmental optimum of the system. However, the aggregation of impacts is not necessary: the system can be optimised on different environmental burdens or impacts simultaneously by using Multiobjective LP. As a result, a range of environmental optima is found offering a number of alternative options for system improvements and enabling the choice of the Best Practicable Environmental Option (BPEO). If, in addition, economic and social criteria are introduced in the model, LP can be used to identify the best compromise solution in a system with conflicting objectives. This approach is illustrated by a real case study of the borate products system.

Abstract: This paper explores the use of LCA as a tool for process environmental management, thereby moving the focus from product to process oriented analysis. The emphasis is on Improvement Assessment in which the “hot spots” in the system are targeted for maximum environmental improvements. In this context, it is useful to use multiobjective optimisation which renders Valuation unnecessary. The approach is illustrated by the case study of the system processing boron ores to make five different products. The results of Inventory Analysis and Impact Assessment are presented and discussed. In Improvement Assessment, a number of improvement options are identified and evaluated, using system optimisation. It is shown that the site environmental performance can be improved over current operation by an average of 20% over the whole life cycle. Thus the study demonstrates that the optimisation approach to environmental process management may assist in identifying optimal ways to operate a process or plant from “cradle to grave”. This may help the process industries not only to comply with legislation but also provide a framework for taking a more proactive approach to environmental management leading to more sustainable industrial operations and practices.

The Imperial Chemical Industries (ICI) group has developed a method, called the “environmental burden system” to rank the potential environmental impacts of its emissions and wastes. The method uses potency factors to characterize the potential environmental impacts of wastes and emissions in ten major impact categories. When compared to the more traditional approach of reporting the total mass of emissions and wastes, the environmental burden approach provides a more meaningful picture of the potential impact of emissions: it helps identi?. the most harmful wastes and emissions; it provides the public with a better understanding ofthe potential impact of company operations: and it helps communicate the effectiveness of waste and emission reduction programs

Clean Technology is an idea which goes beyond Cleaner Production: it concentrates not on a product but on the human benefit which it delivers. Clean Technology is a way of thinking, rather than a set of ‘hard technologies’. One productive approach is through dematerialisation, i.e. providing a service rather than selling a product. This approach leads to the developing idea of Industrial Ecology: the systematic use and re-use of materials. © 1997 SCI.

Social and Environmental Life Cycle Assessment (SELCA) is an analytical tool for profiling and evaluating the interaction between the social and technological systems within the life cycle of given service. Environmental Life Cycle Assessment (ELCA) and Social Life Cycle Assessment (SLCA) are undertaken with their own objectives using independent methodologies. Integrating the outcomes of the two assessments provides more comprehensive and insightful descriptions of the potential impacts of a life cycle, including the key social factors through which the life cycle is sustained and modified. The SELCA approach is outlined using the examples of two fuel cycles of coal and waste in energy-generation. There are some methodological issues in combining ELCA and SLCA which we highlight in order to encourage further work on the integration of environmental and social processes in LCA.

LCA has been developed primarily for industrial production systems. Application to agricultural systems requires systematic application of existing methodology and new methodological developments. Conventional approaches can obscure potential options for improving the environmental performance of systems involving agricultural production due to use of restricted system boundaries, incomplete assessment of impacts, and exclusion of ancillaries from the analysis. For use of nutrients such as phosphorus, it is proposed that Impact Assessment should be based on the quantity dispersed after use rather than on the input to the productive system. Eventually, the impacts associated with depletion should be based on technological or thermodynamic assessment of concentration for reuse, but this approach requires further theoretical development.

Indicators which reflect environmental, economic, health and safety issues, have been categorized as microecometrics and macroecometrics. The former, generally flow based measures, have been developed for local, firm-wide or product based assessments. Microecometrics include materials intensity, energy consumption and emissions data, often from life cycle perspectives. They are, generally, intensive and are scaled with respect to unit of production, GDP or per capita, though other normalization factors have been proposed. In contrast macroecometrics tend to be extensive and represent global conditions such as temperatures and environmental concentrations. Ecometrics are subjective and reflect the dominant value of the individual, family unit, stakeholder group or firm. As such overaggregating or reducing the number of ecometrics for given applications, such as the rating of investments or access to credit, presents potential conflicts. Furthermore, while eco-indicators used for internal corporate reporting should not, necessarily, be validated, those microecometrics which involve external reporting, or multiple stakeholders, are arbitrary if not derived from, or based on, comprehensive life cycle approaches.

The drying performance of a novel device capable of mobilising a bed of fibrous materials is evaluated. The drying kinetic of the vegetable product used for this work, cut lamina tobacco particles, was determined from fixed bed experiments. A falling-rate period was observed for the entire drying curve. The results showed that the drying rate is controlled by internal mass transfer mechanism for gas superficial velocities above 0.8 m/ s. The proposed model is based on an effective liquid diffusion coefficient that varies with solids temperature according to an Arrhenius-type relationship. Batch drying experiments were carried out in the mobilised bed apparatus under various conditions of inlet air temperature, humidity and flowrate. Assuming perfect mixing and no internal resistance to heat transfer for the solids, the performance of the mobile bed can be predicted using the proposed internal liquid diffusion model

One of the main shortcomings of Life Cycle Assessment (LCA) when applied to the Nuclear Fuel Cycle, is that there is currently no recognised procedure to deal with radionuclide emissions in the Impact Assessment stage. A framework which considers both human and environmental impacts is required and a methodology which is compatible with the other impact assessment approaches in LCA must be developed. It is important that the discussion is not only restricted to concepts, but that a working methodology is developed which can be readily applied by LCA practitioners. A provisional method is available for assessing radiological impacts on human health, but no consideration has been given to potential effects on the environment. A methodology is proposed in this paper which assesses irradiation of the environment using Environmental Increments (EI) as the quality standard. This approach is based on the same principles as for the Ecotoxicity classification group, and it represents a working methodology which can be continuously improved as knowledge in the area increases.

Twelve of the main European LCA software packages currently available are examined wirh the aim of establishing which are the most appropriate for LCAs on industrial processes. The packages performances are assessed in terms of• Volume of Data• WindowsTMenvironment• Network Capabilities• Impact Assessment• Graphical representation of the inventory results• Sensitivity analysis• Units• Cost• User Support• Flow Diagrams• Burdens allocation• Transparency of data• Input & output parameters• Demo version• Quality of data

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ISO 14041 requires that allocation by physical causality must reflect the quantitative changes in product outputs or functions and will not necessarily be in proportion to simple physical measure such as mass. This paper examines the instances where physical causality can be represented by mass. However, it also goes further than ISO to demonstrate that the type of causality in the system is not necessarily always the same and can change depending on the way the system is operated. Whole system modelling and the marginal allocation approach are used to identify the correct type of causality for different operating states of the system and the corresponding changes in the environmenta burdens. This is generally not possible with the other allocation methods, also examined in this paper. Both process- and product-related burdens are considered and the approach is illustrated by a reference to an existing system producing five boron co-products.