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Annex 2 Case Study Purpose and nature of the case study The purpose of this case study is to provide an example of a practical, but fictitious application of EnTA. The case study follows the steps described in the Manual and uses the same worksheets. The completed worksheets are presented below, preceded by relevant background information. The potentially serious health and environmental impacts of inappropriate and uncontrolled practices in the collection and recycling of lead-acid batteries are well documented. All stages of used battery collection and re-processing operations are associated with potentially adverse human health and environmental risks, for both small-scale operators and major plants. The focus of the present case study is a private company which plans to construct and operate a secondary lead smelting plant that recycles automotive batteries. The re-processing plant is to be located in Udanax City, the capital of Udanax. The current task is to assess the environmental and related performances of the proposed technology intervention by reviewing, largely in a comparative manner, the environmental impacts of the proposed technology and some plausible alternatives. Setting the scene a. Udanax Undanax is a fictitious country, created by the United Nations Environmental Programme (UNEP) for the purpose of demonstrating the applications of various environmental management tools and systems, as well as for illustrating environmental issues related to technology investments. The following is a brief overview of Udanax. Udanax has an area of 700,000 km2 and 1,100 km of coastline. The terrain is generally flat, with scattered hills (200 to 800 m high) in the central region of the country. There are 15 rivers with lengths over 150 km. The longest river, over 365 km in length, flows through Udanax City before reaching the ocean. The climate of Udanax is temperate to hot, with annual average maximum and minimum temperatures being 30 C and 14 C, respectively. The highest recorded temperature (41 C) was recorded in Udanax City in May, 1959. The lowest recorded temperature of 2 C was observed in January 1960, in the central region. Rainfall averages 650 mm/year in the coastal areas, and 780 mm/year in inland areas. The population of Udanax is approximately 20 million, with six cities having populations greater than 200,000. Some 8% of the population belongs to poor minority groups. Around 50% of the population lives in the coastal areas. Udanax City has a population of 2.3 million. Udanax is not situated in an earthquake zone, but since observations began in the late 1940s one small earthquake has been recorded in the central hilly area. Frequent landslides are observed in the same area, especially during the rainy season that runs from June to September. The coastal areas experience persistent winds, typical of sea breezes. Udanax has a limited supply of minerals, but substantial oil, gas and coal supplies. All electricity is produced by burning fossil fuels. Industry is based mainly on the energy resources, with both heavy industry and light manufacturing. Service industries are moderately well developed. There is a moderate amount of agricultural land and agriculture is reasonably extensive, with export crops based on the limited irrigated lands that produce fruit and vegetables. There is extensive livestock grazing. Tourism is a growing industry, especially in the coastal areas. Commercial fishing is an important export industry, with most fishers belonging to the largest of the ethnic minority groups. Potable water supplies are somewhat limited, coming from both surface areas and groundwater. There is a well developed transportation network. Some 90% of Udanax City has sanitation services, although only primary treatment occurs. Trade waste from the two industrial estates located adjacent to Udanax City are not treated. There are several high schools located in, and adjacent to, Udanax City. One of the two universities is also located in Udanax City. Some university staff members are interested in environmental pollution, and the engineering and science departments occasionally provide technical guidance to those industries that are facing pollution control problems. The majority of the population has had a primary school education and is literate, but the number of individuals with tertiary qualifications is small. Nearly 50% of the working population is employed in agriculture and fishing. Around one third are engaged in work related to government, community, social and personal services. Less that 10% of the workforce is engaged in manufacturing. The political system is a constitutional monarchy, with a Prime Minister and parliament. Water pollution regulations are administered by four inspectors in the Ministry of Resources and Energy. To date the main emphasis has been on the quality of drinking water supplies. The Ministry of Agriculture is responsible for matters related to pesticides and groundwater. Occupational health regulations, administered and enforced by the Ministry of Health, do not yet include chemical exposure limits. Likewise, there are no regulations related to discharges of contaminants into the atmosphere. The Ministry of Planning evaluates environmental impact assessments. Only major projects are assessed. One officer handles these assessments, and advises the Minister accordingly. An Environmental Bureau of four persons exists within the Prime Minister's Department. It is responsible for coordinating environmental programmes, acting as international focal points and advising the Prime Minister. The Bureau has no formal links with other ministries. The waste disposal regulations are administered by the municipalities. In most areas municipal employees collect and transport domestic wastes to one of two dumping sites located adjacent to the industrial estates. Industries employ private contractors, or company staff and vehicles are used. The dumping sites are designed, operated and controlled in ways that are likely to be successful in avoiding or limiting pollution. The following is a summary of the current pollution and waste laws:
b. The proposed technology investment Udanax Recyclers Incorporated (URI) plan to construct and operate a secondary lead processing plant in the West Udanax Industrial Estate, some 30 km northwest of Udanax City and 5 km inland from the coast and Port Udanax. The Industrial Estate is adjacent to Udanax River and the international airport. Both formal and non-formal collection systems currently operating within Udanax will be used to ensure an adequate flow of used lead acid batteries for processing in the plant. Currently approximately half of the lead acid batteries imported into Udanax are collected and the lead smelted in small backyard enterprises. About 25% of the imported batteries are disposed of in landfills and formal dumps. The remainder are disposed of through ad hoc dumping. When the plant is operating it is the intention that all batteries to be collected and ultimately transported to the plant by truck. The domestic supply of used batteries will be supplemented by imported batteries sourced from neighbouring countries. These batteries will come through Port Udanax and will be transported to the plant by rail. Over 20,000 tonnes of scrap vehicle batteries will be processed in an average year. The process flow for the plant will involve pre-treatment (draining, crushing, sorting and separation) and desulfurization of the battery paste. A choice has yet to be made regarding the processing of the treated battery pastes - either a pyrometallurgical process (smelting and refining) or a hydrometallurigical process (electrowinning) will be used, or some combination thereof Frias et al., 2000). The initial preference is to employ the hydrometallurgical process, and this will be the technology that is subjected to the full EnTA - the "long form" of the assessment. The alternatives (three smelting and refining options and no technology intervention) will be compared to the preferred choice, using the "short form" of the assessment. Based on the processing of 20,000 tonnes of scrap batteries, and assuming the battery composition shown in Figure 1, the annual lead treatment would be:
The hydrometallurgical process would combine: 1) Melting of the metallic components such as the connectors and grids. This melting at 350 to 400C separates melted lead from other minor components that remain as supernatant slags or drosses. These drosses will be recycled to the hydrometallurigical treatment line. A pot or crucible will be used for this melting process. The resulting product will be alloyed lead, of similar composition to original grids and connectors. A ventilation system surrounding the melting pot will be required. Any fume captured in the ventilation bag filter will also be sent to the hydrometallurgical line. No slag or solid residue will be generated; and 2) Hydrometallurgical treatment of the battery pastes, together with a small portion of the drosses, fume, slags or imported lead sulphide. The resulting product will be 99.99% pure lead (7,100 tonnes per year) and lead cement with impurities (400 tonnes per year). The lead cement will be melted to give, for instance, lead quality for shots, or even mixed with the alloyed lead produced in the melting line. The hydrometallurgical process offers two approaches for the gypsum product. In one instance the gypsum would not be recovered as a by-product - a residue from the leaching step would be generated containing more than 80% gypsum weight. This is an inert residue. Alternatively, battery pastes would be desulphurated by adding lime prior to the hydrometallurgical treatment. In this case a clean gypsum by-product would be produced. In addition, a small amount of leaching residue would be produced. This would also likely be classified as an inert residue. The second option would require additional equipment and result in higher operating costs in comparison to the simpler approach. Hence the second approach will be taken only if a commercial application for the synthetic gypsum can be identified. The plant will be designed to meet all the environmental protection regulations currently in force in Udanax. However, in anticipation of the strengthening of these regulations, including the air quality standards, the plant owners have decided to comply with much higher standards than are currently in force. It is hoped that the chosen process technology will also allow the plant to gain ISO 14001 certification. With increasing private vehicle ownership, within both Undanax and the region, the plant owners consider the growing supply of used lead acid batteries will ensure the economic success of the enterprise. They also plan to construct and operate a battery manufacturing plant, which is to be located in an adjacent part of the Industrial Estate. They envisage considerable economic and other benefits will arise from this integration. A preliminary assessment of the economic performance of the proposed technology intervention has been undertaken, following the methodology presented in Annex 3 of the EnTA Manual. The results are presented in Table 1. The proposed development has been supported by both the central and municipal government authorities. They believe the technology intervention will take advantage of a resource that would otherwise be sent to a landfill, dumped inappropriately or partially recovered in the informal lead smelting sector. All three of these current recycling or disposal options have significant environmental, social and economic implications. The initiative is also seen as an example to other industrialists, especially with respect to the desirability of improving environmental performance. The planned investment will go a long way to reducing the country's dependence on imported automotive batteries. It also signals confidence in the local economy and will hasten further development of the country's industrial sector. Representatives of people living in residential communities adjacent to the
Industrial Estate are very upset with the proposal to construct the plant. Their
preference is for the plant to be built in the interior of Udanax, where other
refining operations are already located. Community concerns relate principally
to the pollution of the river and the groundwater, and to the release of
particulates and fumes from the plant, with possible adverse impacts on the
health of both children and adults living in the residential areas down wind
from the plant. The community leaders are supported in this regard by national
non-governmental organizations, and by two major international environmental
organizations. They too wish to see the plant located in the interior. The plant
owners argue that they will be using state of the art equipment and processes,
and there will be no adverse effects on the environment. They also feel that if
the plant had to be located some distance from Port Udanax the operation would
be uneconomic, due to the increased transport costs.
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