Assessing the environmental impact of metal production processes

Evaluating both new and existing processes for primary metal production to assess their environmental impacts is often difficult due to the many inputs and outputs involved. Life Cycle Assessment (LCA) is a methodology that can be used for such purposes to identify those parts of the metal production life cycle that have significant environmental impacts. LCA has been used by CSIRO Minerals to assess the “cradle-to-gate” environmental impacts of a number of metal production processes practised either currently or potentially in Australia. The metals considered included copper, nickel, aluminium, lead, zinc, steel, stainless steel and titanium, by both pyrometallurgical and hydrometallurgical routes in some instances. The environmental profile included greenhouse and acid rain gas emissions, solid waste emissions and gross energy consumption. The results for various metals are compared in this paper. New process technologies for primary metal production can be expected to reduce the environmental impacts of metal production, and estimates of likely reductions for technologies involving stainless steel, titanium and aluminium are also presented in this paper.     

The use of Environmental Management Accounting (EMA) for identifying environmental costs

The Expert Working Group on “Improving the Role of Government in the Promotion of Environmental Management Accounting (EMA)” was set up by the United Nations Division for Sustainable Development (UN DSD) in cooperation with a number of government agencies and non-governmental experts to promote Environmental Management Accounting (EMA) through publications, pilot projects and by establishing an international forum for discussion on the role of governments in the promotion of EMA.EMA, Environmental management accounting represents a combined approach that provides for the transition of data from financial accounting, cost accounting and mass balances to increase material efficiency, reduce environmental impacts and risks and reduce costs of environmental protection. EMA is performed by private or public corporations, but not by nations and has a financial as well as a physical component.The core focus of environmental management accounting and of the EMA UN DSD methodology is assessment of total annual environmental expenditure on emission treatment, disposal, environmental protection and management. In addition, and that is new and challenging for most companies, the material purchase value of all non-product output and its production costs are added. This total sum often provides a frightening picture of total annual costs of inefficiency and gets companies to improve their information systems and material efficiency options, which is the goal in the light of cleaner production.The first book published by the Expert Working Group, Environmental Management Accounting—Procedures and Principles (Jasch, C., United Nations, New York, 2001), defines principles and procedures for EMA, with a focus on techniques for quantifying environmental expenditures or costs, as a basis for better controlling and benchmarking purposes. The methodology excludes costs external to the company (so-called externalities, e.g. environmental and social effects that occur to the general public), but focuses on comprehensive assessment of direct annual expenditure on emission treatment, environmental protection and management as well as wasted material and energy input (efficiency losses in production). Firstly, total annual expenditure is assessed, then improvement options, savings and investment projects as well as product prices can be (re-)calculated. The method is currently applied in several case studies. The following summary provides some of the core definitions and generic assessment tables.     

多晶硅光伏组件生产可持续性评价

分别采用了全生命周期评价软件、全生命周期成本法、社会性指数评价法,对我国多晶硅光伏组件生产阶段的环境影响、经济性和社会性影响进行了定量评估.结果表明:多晶硅生产、多晶硅电池片生产、电池组装3个阶段的环境影响相对较大,其中多晶硅生产阶段对气候变化的贡献率在50%以上.经济成本分析显示,原料和劳动力的成本占总成本的70%以上.多晶硅电池片生产阶段的成本在光伏组件生产过程的5个阶段中所占的比重最大.社会性影响分析结果显示,在光伏组件生产中,劳动岗位增加的贡献指数值为0.72,劳动力就业贡献较大,而生产能力提高的贡献指数值仅为0.18,显示生产能力提高的贡献较小.研究显示,为提高多晶硅光伏组件的可持续性,在生产过程中需寻找清洁能源、寻找环保替代材料以降低环境影响;积极鼓励支持企业进行技术研发创新,着力提高电池转换效率以降低生产成本;通过市场良性竞争提高多晶硅光伏行业的社会贡献.      

中国光伏电池组件的生命周期评价

在收集2009年我国光伏组件生产的主流及最优技术水平数据的基础上,采用Ecoinvent数据库中辅助材料的生命周期数据,开展了我国光伏组件生命周期评价研究,计算了能量回收期和全球变暖潜值,并探讨了不同生产步骤和生产参数的影响.结果表明:太阳能级多晶硅生产和铸锭、切片工艺的技术水平对光伏产品的能量消耗和环境影响最大,我国主流技术水平情景下的产品能耗和环境影响远大于最优技术水平.对于我国光伏产业来说,要降低光伏产品的环境影响,应着重从改进多晶硅生产技术和提高硅片切割效率入手.      

Emergy as a tool for Ecodesign: evaluating materials selection for beverage packages in Brazil

The life of a product begins with the initial product design concepts; the costs and potential impacts of a product are heavily influenced by the final design, the production processes, the economic and environmental costs of all raw materials. Additionally, both of these factors are very much affected by how the products are managed during and after consumer usage. Thus, there is an urgent need for a tool to facilitate the integration and assessment of environmental and economic demands into the product planning and development processes. The introduction of environmental accounting based on emergy as a tool to assist in product design is proposed. This complementary tool may be inserted into the conventional design methodology to facilitate in the selection of materials and processes as well as in the actual design of the products. To illustrate the application of the proposed method for material selection, PET (polyethylene terephthalate) bottles and aluminum cans for beverage packaging are compared. Despite the exceptional condition of aluminum recycling in Brazil, results show that the best option for beverage packages is the PET bottles.     

Environmental management accounting as a reflexive modernization strategy in cleaner production

Understanding the material purchase value of wastes and emissions and related processing costs is the essential contribution of an Environmental Management Accounting methodology proposed by a United Nations expert working group organised through the Division for Sustainable Development (UNDSD). Tracing costs and benefits according to this UNDSD methodology, considered as a “reflexive” modernization strategy in this article, sheds new light on cleaner production initiatives for corporate sustainability. Information on the first category of costs, waste and emission treatment, is generally the most accurate. Information on the second category, prevention and environmental management costs, is more difficult to determine because this category overlaps with, or is confused with, the first category of costs. Data for the two novel and innovative cost categories of the material purchase value of waste and emissions and related processing costs are even harder to obtain. Frequently, the costs are either hidden in overhead accounts or are not recorded because they are not required in conventional accounting systems. The outcome is that companies, even though they may profess otherwise, have very little knowledge about their full environmental costs, cost saving opportunities, or how best to achieve cleaner production initiatives to promote corporate sustainability. A more systematic application of the UNDSD EMA methodology would provide a better record of costs and act as a catalyst in promoting cleaner production processes. This application inevitably requires “reflexive institutions” including “reflexive corporations”, that is, corporations with the capacity to examine the side effects of their operations as modernization rebounds upon them.     

Application of Ecological Footprint Analysis on nectarine production: methodological issues and results from a case study in Italy

Ecological Footprint Analysis (EFA) is an environmental accounting system that provides an aggregate indicator which is both scientifically robust and easy to understand by non-experts. Although based on the lifestyle consumption of natural resources, recent improvements in the methodology now allow the application of EFA to a final product. Thus the resulting footprint value represents the environmental cost of all of the activities required to create, use and/or dispose of a particular product. The application of EFA to agricultural systems is still uncommon and examples in the fruit sector rare. In this work a detailed application of EFA to a commercial nectarine orchard in Piedmont (Italy) is presented. In contrast to previous studies, we considered not only the one-year field operations, but also the whole lifetime of the orchard. The calculation was conducted for six different orchard stages: (ST1) nursery propagation of the young plants; (ST2) orchard establishment, (ST3) young trees producing low yields, (ST4) mature trees at full production, (ST5) declining trees with low yields, and finally (ST6) orchard removal. The environmental costs at each stage are presented and related to each other on the basis of the relative footprint value. Results highlight the importance of applying EFA to the entire lifecycle of orchard production: ST4 accounted for the majority of costs at 65% followed by ST2, ST3 and ST5 at or near 10%, whilst the costs of ST1 and ST6 were negotiable. Thus it is the type of ST4 production used which can have the greatest impact on EFA values.     

Application of a Life Cycle Impact Assessment framework to evaluate and compare environmental performances with economic values of supplied coal products

The South African economy is strongly based on coal as a mined resource, and various grades of coal are supplied to local and international customers. However, the environmental impacts associated with the preparation and production of different coal grades from Run of Mine (RoM) or raw coal are variable; specifically, the different mining methods used for coal extraction – opencast or underground mining – have different environmental impacts. The entire life cycles of the grades of coal must therefore be evaluated in order to compare environmental performances with supplied economic values. In this paper, a Life Cycle Impact Assessment (LCIA) methodology, based on the ISO 14040 standard, is applied for this purpose. Four cases are considered in South Africa: typical high-grade and low-grade coals from opencast and underground mines.     

中国煤炭环境成本内部化的经济影响分析

对煤炭开采、运输和使用各个环节的环境污染和生态破坏外部成本进行核算的基础上,运用GREAT-E模型对煤炭环境成本内部化政策给GDP、居民收入、产业结构和贸易竞争力等带来的影响进行了定量分析.分析结果表明,煤炭开采、运输和使用各环节分别进行的环境成本内部化对中国宏观经济的影响较为有限,GDP的下降在可承受的范围之内,即使是全生命周期的煤炭环境成本完全内部化也只导致GDP出现0.15%左右的轻微下降.煤炭环境成本内部化将促进劳动力和资本等要素从高耗能行业向低耗能特别是技术密集型和现代服务业部门转移,进而推动产业结构优化转型升级.在煤炭生产、运输和消费环节通过征收环境相关税费能够更直接地刺激生产部门的环境行为调整,降低煤炭的生产和消费量,进而减少环境污染和生态破坏.     

A multiple-criteria environmental impact assessment for the plastic injection molding process: a methodology

This paper proposes a multiple-criteria methodology for evaluating environmental impacts in the plastic injection molding process (PIMP) and incorporates the findings of an empirical study conducted in Hong Kong. The paper identifies and explains various indicators of environmental impact assessment and establishes a multiple-criteria rating matrix. It then elaborates on the implementation of a pilot program and discusses the relevance of the methodology inside and outside of the work environment. Results show that the methodology provides manufacturers with a feasible means to assess their environmental performance and perform benchmarking analysis. The methodology can also be modified and applied in different industry sectors.     

Multi-objective modeling and optimization for cleaner production processes

The paper presents a methodology for multi-objective modeling and optimization with environmental impacts and economics aspects simultaneously in the context of cleaner production. A generalized multi-objective process model is proposed based on a holistic concept of macro-structure. A hybrid multi-objective evolutionary algorithm is proposed to solve this multi-objective optimization problem. The Elitist Non-dominated Sorting Genetic Algorithm is used to obtain the Pareto-optimal set. The best compromised solution is determined by using the Technique for Order Preference by Similarity to the Ideal Solution. A simple reaction system is presented as a case study to illustrate the proposed methodology.     

Environmental,financial and quality assessment of drinking water processes at Waternet

Waternet (formerly Amsterdam Water Supply) has been seeking a sustainable scenario for producing drinking water and offering services that fulfill the requirements of clients and regulations, and, at the same time, maintains a sound environmental performance while keeping costs as low as possible. Presently, the company is in the process of evaluating alternatives for the treatment of water that cause the least financial and environmental impacts. The quantification of these impacts, for the current conditions, was carried out in earlier investigations. However, until now, the water quality aspect was not yet considered.In order to include this water quality aspect into the financial and environmental assessment, a quality function was constructed created by comparing water quality parameter values for a current and an alternative treatment process. Four qualifications were assigned to the sum of these scores: “Worse”, “Same”, “Better” and “Much better”. The qualifications allowed the comparison of the water quality and the financial and environmental impacts of the selected alternatives using a graphical representation of them.The method was applied focusing on the environmental and financial assessment of six alternative processes for the Loenderveen–Weesperkarspel treatment line, and including the quality aspect, as a third parameter for comparison.     

Trends in the small-scale mining of precious minerals in Ghana: a perspective on its environmental impact

Small-scale mining in Ghana is defined to include both the exploitation of mineral deposits (1) using fairly rudimentary implements and/or (2) at low levels of production with minimal capital investment. While the large-scale mining—of particularly gold—has become predominant, small-scale mining, which predates such operations, has continued to be an important economic activity, particularly within the remote and poorer areas of the country. The environmental impacts of such small operations have, however, varied, depending on methods and the scale of operation. The factors that have contributed to aggravating these environmental impacts are economic, technical, legal, and operational in nature. Although mitigation efforts have had a limited impact, it is expected that the measures now being considered for adoption will improve the efficacy of the Government of Ghana’s drive towards improving environmental management in resident small-scale precious metal mining operations.This paper examines the environmental impacts of small-scale mining in Ghana—with particular emphasis on precious minerals and metals extraction—and outlines a series of initiatives for improving environmental performance in the industry.     

Life Cycle Assessment for biodiesel production under Greek climate conditions

The aim of this paper is to understand and to model the environmental performance of biodiesel produced by various Greek raw materials under current conditions. Three energy crops (rapeseed, sunflower and soybean) have been studied, with regard to their levels of biodiesel productivity. Throughout the entire process, current Greek climatic conditions and cultivation parameters have been taken into account. At the stage of assessment, we conclude that the environmental impacts per crop area indicate that soybean has the lowest environmental impacts. However, by assessing the results per quantity of produced biodiesel, the crop with the minimum environmental impacts is sunflower. This paper shows that environmental benefits from biodiesel have better results, compared to conventional diesel, thus leading to the conclusion that it is feasible to succeed improved environmental performance.     

Environmental and economic assessment of biomass sourcing from extensively cultivated buffer strips along water bodies

Buffer strips represent oblong land elements along water bodies playing an important role for the water quality management of the surface water. In the policy context buffer strips are referred to as land with defined farming restrictions aiming at protecting the water course. In the current EU agricultural policy framework the majority of the decisions regarding subsidy schemes for buffer strips is taken on the member country level, which results in great differences between the EU members with regard to this water protection measure. If incentives for farmers for establishing and maintaining buffer strips are in place, they are usually linked to the harvest ban on the buffer strip. Such protection model can be endangered by volatile and rising prices for agricultural products. However, buffer strip can represent a valuable source of different ecosystem services, including biomass provision. If harvesting under certain restrictions would be allowed, the biomass could generate additional revenue that might contribute to securing buffer strips existence and consequently maintaining their protection function.This study aimed at assessing the costs and environmental consequences of biomass mobilizing from buffer strips. It dealt with different scenarios of biomass sourcing from extensively cultivated buffer strips in the Netherlands. In 12 scenarios, the cultivation of grass or cereal mixes (including multiple harvesting or perennial cultivation) for different valorisation chains (ensiling or fodder & bedding) was assessed. Both total net cultivation costs as well as the hectare based environmental performance (using the Life Cycle Assessment methodology) were evaluated. Additionally, the environmental impact of electricity production through anaerobic digestion of biomass from buffer strips was compared with the impact from digestion of classic grass silage and the impact profile of Dutch electricity mix.The results indicate ensiling as the scenario generating more net costs and higher environmental impacts as compared to fodder & bedding. In the latter, the cereal cultivation represents a better solution from economic perspective, while grass shows lower environmental impacts. Moreover, optimizing grass cultivation through switching to perennial mode contributes to strong improvements of the economic performance and contributes to additional reduction of environmental impacts, and consequently delivers the best environmental and economic solution. Moreover, the comparison with the Dutch electricity mix shows that biomass from buffer strips, if used in anaerobic digestion, can, in terms of environmental performance, compete with classic silages and contribute to reduced environmental damage.     

Environmental costs at a Canadian paper mill: a case study of Environmental Management Accounting (EMA)

An Environmental Management Accounting (EMA) framework is applied to the 2000 year-end financial report for the Mackenzie Paper Division paper mill owned and operated by Abitibi-Consolidated Inc. of Montreal, Quebec. A conventional reading of the obvious environmental costs from this financial report is Cdn$2,196,838. This figure is derived from an analysis of effluent treatment costs and other line item environmental costs. There is no “environmental account” category that breaks out either costs or the mass balance of inputs and outputs. For the most part, environmental costs are rolled up into overhead accounts such as administration, infrastructure and materials accounts.Application of the EMA framework is based on assigning environmental costs to one of four categories for which a tentative breakdown is as follows: (1) waste and emission treatment costs ($3,348,902); (2) prevention and environmental management costs ($270,109); (3) material purchase value of non-product output costs ($946,799); and (4) processing costs of non-product output ($2 92,943). There is also a category called Environmental Revenues, of which none were reported. Conservative estimates thus place the total environmental costs at $4,858,753.What is significant about this result is that the environmental costs under EMA are at least twice as much as would normally be reported. This supports the view that environmental costs are much higher than generally considered and makes it clear that many important environmental costs as well as benefits are “hidden” in other accounts. More studies of a similar design are required to confirm the validity of the EMA methodology reported here.     

Environmental impacts of cocoa production and processing in Ghana: life cycle assessment approach

Ghana is the world's second largest producer of cocoa beans. In addition to exporting raw cocoa beans, the country also processes some of its beans into finished and semi-finished cocoa products for both the local and international markets. This paper is aimed at providing a comprehensive picture of the environmental impacts associated with cocoa production and processing in Ghana by applying the life cycle assessment (LCA) methodology. The analysis considered the entire system required to produce and process 1 kg of cocoa bean. It included the extraction of raw materials (e.g. fossil fuels, minerals), the production of farming inputs (e.g. fertilizers and pesticides) and all agricultural operations in the field (e.g. tillage, fertilizer and pesticides application, harvest, etc.). Transportation of beans to processing factory and industrial processing of the beans into cocoa butter, liquor, cake and powder were also included. The study was conducted in accordance with the international ISO procedural framework for performing LCA in the ISO 14040–14043 series.The overall environmental impacts resulting from cocoa production and processing activities and improvement options towards the sustainability of the system studied are presented and discussed.     

Material flows and environmental impacts of manufacturing systems via aggregated input–output models

Manufacturing processes may be viewed as operational units in the overall manufacturing/production system. Changes in technology, production patterns, and process settings are typically made at the process (unit) level. Very often, environmental problems are apparent when the manufacturing/production system is viewed as a whole (many units joined together). However, with the units aggregated to form a system, it is often difficult to identify the source of an environmental problem or judge the singular effect of changes to a process unit; the changes become lost in the complexity of the system as a whole. Recent efforts have employed input–output modeling to describe the flow of materials and the environmental consequences associated with manufacturing processes. A method is introduced for aggregating process-level material input–output models to form a combined material input–output model for a manufacturing system. The resulting model serves as a bridge between unit-level changes and broader system behaviors. The model form permits identification of opportunities for reducing environmental impacts at the process level (e.g., reduction of emissions, waste generation, and material use) and driving the system toward zero emissions based on an examination of the aggregated manufacturing system level model. Case studies are used to illustrate the application of the aggregated material input–output model to minimize waste and resource consumptions.     

道路环境成本的货币化模型研究

公平、合理地分担外部性环境成本是实现道路交通资源最优配置的前提条件之一,而环境成本货币化评估是实现道路交通政策体现环境公平性的重要内容。介绍了在国内外对道路外部成本的研究成果,在已有研究的基础上,将我国道路交通发展的环境成本主要分解为生态影响、环境污染和温室气体排放三类,并以借助环境经济学理论基础,对给出的道路交通生态影响、环境污染和温室气体排放的货币化方法估算模型分别进行了探讨。随后,以安徽省某高速公路为例,计算出道路建设及运营的环境成本占工程总投资的7.31%,结果表明环境成本货币化有利于明确道路建设的环境影响,并纳入成本核算中。