Recovery from scrap batteries

Code No: TMS111 Price: Rs1600/- Category: Energy: Generation

 

1.1 Introduction

1.1.1 Recycling of used batteries for recovery of lead in India is not new. Extensive secondary processing has been a feature of the lead industry in India and abroad. In India secondary lead is being produced both in the organized and unorganized sector by conventional means which are not environmentally conductive except of course in a few cases where pollution control measures have been adopted in organized sector. Un organized sectors including backyard small units, distributed in many parts of the country, have been operating without any restraints and concern to the environment and health of workers and those living in the vicinity of such units. Almost 250 of the small units, which were operating in Delhi have been closed. Most of these, however, have been shifted and are now in operation around Delhi, this has only brought about a shift in the coordinates of the centers of pollution effectively.

Streamlining the recycling system of battery scrap and development of a healthy secondary lead producing industry is needed. The industry is important, as even today it supplies almost 70% of the total lead consumed for various industrial applications.

With the rapid growth in the automobile industry and hence the requirement of batteries, battery scrap generation will also increase proportionally commensurate with the production of number of batteries which is expected to reach a record 37 million mark by the turn of the century.

Future of battery scrap recycling industry is, therefore, very bright provided that it is combined with efficient and environmentally compatible and, of course, economically viable technology.

Battery Recycling Technology

They type of technology for processing battery wastes hitherto practiced in India and abroad, necessitated separation of organic components of the battery involving arduous labour, intensive manual method or supported by the use of mechanical saws and guillotines. Lead component was processed in conventional furnaces which generated toxic gases and other solid wastes which created health hazards and environmental pollution.

The methods of segregating the battery components have been replaced by new processing techniques with considerable improvements in the technology.

Alternative processed of treatment of metallic portion for extraction of metal and it’s refining have also been investigated keeping in view the environmental needs by various international research centers, institutes and industries. Several new technologies have evolved as a result of these efforts. Some of them have already been used on industrial scale with advantage while others have been tested on pilot plant scale and are awaiting industrial application. The trend has been to develop hydrometallurgical / electrochemical processed against conventional pyrometallurgical processed both from environmental and cost consideration.

The new technologies aim at the following:

- Efficient recovery and processing of metal from scrap
- Recovery of other products.
- Closed circuit operations to minimize the liquid and gaseous effluents or solid waste disposal problems and associated hazards to health and environment.

In view of emerging need for establishing additional secondary lead smelters to cop with the increasing amount of used battery scrap and availability of environment – friendly technology out of several alternative options, the issue of “Recovery from battery scrap” needs a thorough examination to selecting bet technological route in India.

1.1.2 In this context, this report, “Techno- Market Survey on Recovery from Battery Scrap in India and abroad” has been prepared. It focuses on recovery of metals that go into the making of lead acid or a few household batteries viz lead, mercury, cadmium and nickel with stress on:-

- Selection and recommendation of appropriate technology for battery processing and extraction/refining of metal(s).
- A technology which is pollution free in comparison to conventional pyrometallurgical process of recovery used in India and may other parts of the world.
- A technology that generates no or less rejects in soil, liquid ad gaseous form.
- A method suitable for Indian conditions – efficient and economical.

1.1.3 Scope and Coverage

1. Relationship and the importance of the specific topic to the broad area to which it belongs.

2. The current status of the plating waste recycling and recovery technology in the world and in the country. Market (domestic and export) sizes and their potentials.

3. Assessment of the technology, resource parameters such as energy, raw material, infrastructure and manpower etc. to arrive at preferred technology options available to the country.

4. Short term and long term economic aspects preferred options along with their feasibilities.

5. Impact of the preferred options by itself and its spin offs.

6. Recommendations:

i) For implementations of preferred technology option(s) indicating critical inputs such as raw material, capital goods and human resources required and their availability, investments required to commercialize, and benefits/returns expected. Maximum possible quantification is required.

ii) For R&D / Technology development indicating the requirement of inputs and expected benefits.

7. Action Plan for implementation of recommendations alongwith identification of:

a) List of available technologies for Indian industry and
b) The agencies/groups/individuals for implementation.

8. Expected impact of recommendations, if implemented.

1.1.4 Methodology

The study has been carried out based on secondary data comprising study of current literature available with various libraries, information centers, institutes. Subject matter has also been drawn from articles, corporate news, proceedings of various national and international seminars and various periodicals and technical magazines. Personal discussions with eminent experts, professionals, battery manufactures, metal and scrap dealers, motor garages, auto-electric repair and maintenance centers, battery dealers have also supplemented the information relevant to the subject matter of this survey. The questionnaire were issued to reputed international organizations engaged in battery manufacturing trade and development of technology of processing battery scrap and their response has been utilized in preparing the report.

1.1.5 Limitations

Due to geographically widespread battery manufacturing and secondary lead smelting facilities and users of batteries it has not been possible to visit all the relevant places. Technological development in this field has taken place in other countries and were not accessed to them directly. Since India uses the conventional lead smelting process for secondary lead production and excepting a few cases where additional equipments have been installed to minimize pollution, there has been no significant technological development in the country.

1.2 Major Observations, Findings & Analysis
1.2.1 Recovery from battery scrap is not new to India. Some of the major battery manufacturers have their own battery processing facilities and these are secondary lead smelters in organized sector in the country. In addition there are above 250 small plants and may backyard units which produce lead from the battery.

1.2.2 Battery scarp indirectly falls under he category of hazardous wastes and its transport, storage, processing and disposal is governed by Hazardous Wastes (Management and Handling) rules, 1989 and relevant guidelines issued by Ministry of Environment and forest under he Environment (Protection) Act, 1986. Basel Convention regulates the transboundary movement, storage and processing of all hazardous wastes (including battery wastes, though, not specifically mentioned) in the international context.

1.2.3 Legislation in Other Countries

In may countries, specific legislation for spent battery wastes, their collection, storage, processing and disposal have already been implemented as for example in may states in USA introduced at in many EEC countries legislation is under the drafting or implementing stage. The legislation aims at controlling the disposal of batteries and enforce heir return for processing and have the following principle features:-[5]

- A requirement for retailers and others selling batteries to end-users to accept used batteries on exchange basis.

- A requirement for battery wholesalers to accept used lead batteries from customers in a quantity at least equal to new batteries purchased and to remove used batteries from retail points within 90 days.

- The imposition of additional charges on the selling prices of a new battery, redeemable when a spent battery is returned to the point from which the new batteries is purchased.

- Direct prohibition of the disposal of spent batteries in solid waste landfills.

1.2.4 A battery after it has reached the end of it’s useful life is a waste so far as an automobile is concerned. Disposal of these, as other wastes, into the Municipal Solid Waste (MSW) stream is undesirable due to two reasons:-

1) Discarded bvatteries contain good amount of lead (lead acid batteries), mercury, cadmium and nickel (mercury nickel-cadmium batteries).

2) Lead, cadmium and mercury are highly toxic metals and should not be allowed to pollute water or food. Recycling of batteries therefore serves two purposes. Useful metals so much needed are recovered and poisonous substances are prevented from entering the environment.

1.2.5 Lead is a metal which, because of its physical and chemicals properties, finds many other industrial applications viz. gasoline additives, rolled and extruded products, alloys, pigments and other compounds, cable sheathing, shot and ammunition and many other miscellaneous new uses.

Its use in many applications viz. gasoline additives, pigments (household paints), etc. is being discouraged. Battery sector, on the other hand, is consuming more and more lead due to accelerated growth of automobiles sector, less so in developed countries but phenomenally high in developing countries like India. The consumption of lead in batteries exceeds 50% of the total lead used in the country. Its demand is ever increasing.

1.2.6 Demand and Supply

1.2.6.1 World Position

The world demand for lead has reached a record level of 5.6 million tones in 1995 out of which 65% has been accounted for OECD countries. Out of this total 63% is shared by battery sector alone.

1.2.6.2 Indian Scenario

The primary smelters, chanderia (Rajasthan) and Tundlu smelters (Bihar), are based on ores/concentrates of Indian origin have an overall capacity of 33,000 T/yr each. Vizag smelter in Andhra Pradesh has an installed capacity of 22,000 T of lead per year. The production from secondary lead producing smelters and backyard units is of the order of 45,000 T/yr, thus making a total of 100,000 tonnes of lead capacity.

- The total primary production in 1994-95 was 34,776 T and that of secondary lead 37,223 T i.e. 71,699 T of lead in total. In addition to this the country imported 21,000 T of lead, this brings the availability of lead to 92,699 T against requirement of 115,000 T.

- India’s demand for lead in 1995-96 is place at 122,000 tonnes. The projected demand by the turn of century is placed at 154,000 tonnes which will rise to 206,000 tonnes by 2004-05.

- As against the demand the supply is placed at 86,500 tonnes. A demand supply gap of 35,000, 67,500, 119,500 tonnes in the year 1995-96, 1999-2000, 2004-2005 respectively, is expected.

1.2.7 Significance of Secondary Lead-Recycling of Lead Bearing Scrap

Secondary sources of lead production is based on recycling of lead scrap, of which dominant share is held by spent lead acid batteries. Lead acid batteries, despite its having been classified as hazardous waste, are an important secondary source of lead. This is important in the context of our limited natural lead resources and limited lead production capacity not likely to expand significantly unless rich large deposits are discovered in near future. Primary lead production on the other hand will always be essential since even after 100% recycling efficiency, there will always be a gap between demand and supply of lead in the country.

1.3 New Technological Options

In addition to the secondary lead producing smelters using conventional, technology, recently National Metallurgical Laboratory, Jamshedpur has developed a process for secondary lead production from battery scrap and has initiated an in-house project “pollution control in small lead scrap smelting furnaces”.

1.3.1 A number of technological options are available for recycling battery scrap, the most important among them being:-

a) KHD-WET MECHANICAL PROCESS g) KIVCET PROCESS
b) PLOMBREC PROCESS h) ISASMELT PROCESS
c) PLACID PROCESS i) KEPAL-ZV PROCESS
d) CX-EWS PROCESS
e) EXIDE PROCESS
f) OXYGEN ELECTRO- THERMIC PROCESS

A critical review of all the nine processes was carried out. The observations can be summarized as follows:

- KHD wet mechanical process with a capacity of 10,000 T of scrap per year will cost nearly Rs. 24 crores and compares favorably with a plant recently installed at a cost of Rs. 40 crores including Rs. 2 crores worth of equipments for air pollution control in the pyrometallurgical process. The process is therefore recommended for consideration.

- Plomrec process is a hydrometallurgical process, compact low temperature operations, a few chemicals are used which are easily available i.e. KOH and NaOH, the products K2SO4 and plastics which can be used in fertilizers and in Indus tries respectively thus eliminating the waste disposal problem to a great extent. The process is an established one and is expected to be cheaper them KKD wet mechanical process due to it’s low temperature operation resulting in inexpensive material to be used in making the plant, long life of the equipment and low power (electricity) required for heating and electrolysis. The process thus deserves consideration.

- Placid process is also a hydrometallurgical process, environmentally safe but is still in pilot plant stage. Indus trial setup and performance results are yet to come. This process utilizes lead paste and has to be integrated with a pyrometallurgical plant to treat the grids. The process leads to recovery of all components and is environment-friendly and expected to be economical, hence it is recommended.

- CX-EWS process will require CX process to be integrated with it (to precede it) for obtaining the lead paste for lead extraction. Grids will have to be treated in conventional pyrometallurgical plant and therefore, will be costlier than plombrec and placid process. Hence it is not recommended. Moreover only environmental reasons cannot motivate a shift from a well known pyrometallurgical process towards the advanced technology which is rather new and unproven unless more stringent anti-pollution laws are passed and enforced.

- Exide process adopts the pyrometallurgical extraction of lead and therefore, from cost consideration, it will match the CX-EWS process. In addition it is accompanied by waste generation (slag) which will have to be disposed off, together with water effluent. The process is therefore, not recommended.

- Oxygen-electrothermic process employs pyrometallurgical plant for lead extraction. Cost is high and hence it is not recommended.

- Kivcet process-sufficient details are not available but the process involves pyrometallurgical operations and will be costlier than plombrec process. Hence it is not recommended.

- Isasmelt process is comparable to Kivcet process and in the absence of sufficient details proper evaluation of the process was not possible for dependable assessment of its merits and demerits.

- Kepal-zv process is a hydrometallurgical cum electric smelting unit. The process is expected to cost much less as compared to conventional pyrometallurgical route but no cost data is available. However, the process appears attractive. In this report though, the process has not been recommended.

1.3.2 A techno-economic comparison of these options have been attempted. Availability of inadequate data on capital and operating costs and some other details required for precise estimates has been a serious constraint. Nevertheless, based on the order of magnitude cost estimates available for some options, the total cost of one of the plants recently installed in India has helped in working out comparative cost of various technological options.

1.3.3 Based on this comparison the following options have been short listed:

- KHD PROCESS
- PLOMBREC PROCESS PREFERRED TECHNOLOGIES
- PLACID PROCESS

- EXIDE PROCESS
- OXYGEN ELECTRO-THERMIC PROCESS
- KEPAL-ZV PROCESS

1.4 Recommendations

1.4.1 Recycling of battery scarp undoubtedly has a bright future. Improved and environment -friendly technologies are now available to replace the conventional pyrometallurgical operations which are a source of environmental pollution. These two factors however, are not sufficient for optimum recycling of battery scrap. The weakest link in the chain is the aspect of RETURN OF BATTERY SCRAP FOR PROCESSING. This requires an efficient system for collection of used batteries.

1.4.2 Used Battery Collection System

1.4.2.1 In order to improve the battery recycling rate, it is recommended that a worming group consisting of representatives from Ministry of Environment & Forest, lead industry, battery manufacturers, scrap traders and smelters should be established to look into the following aspects:-

- Ways and means of finding a scrap collection system by analyzing the schemes that have been introduced by some of the EEC countries.

- The impact of international conventions ad agreements such as Basel Convention and general agreement on tariffs and trade in terms of lead-acid battery trade should be considered. The need for the acceptance of any kind of indigenous or imported lead-acid battery by traders or manufacturers and not only the brand originally sol tat a retail point.

- Direct prohibition of the disposal of spent batteries in solid waste land fills becomes an environmental regulation in India.

- Campaigns are to be launched to make people aware of their social responsibilities to return used batteries to scrap collectors/smelters.

- Battery sales data and statistics on spent battery returns are vital in determining battery recycling rates. Organizations like India Lead-zinc Information Centre, Indian Institute of Metals could assist the industry by acting as a central data collection point. This data would enable the centre to assess whether there is an improvement in battery recycling rates on an organized basis and make this information available to the industry.

1.5 Action Plan

1.5.1 Technological Option for Recycling used Battery Scrap

Out of the selected three technological routes, KHD wet mechanical process, Plombrec process, and placid process, final choice should be based on the appraisal of the status of new technologies specially hydrometallurgical or electrochemical process of extraction of metallic and organic constitutes of battery and minimum waste and effluents generation for all processes.

1.5.2 Pre-processing of batteries for separation of its metallic and plastic constituents is a simple process and can be designed and optimized within the country.

Research and experiments should be taken up on priority basis to develop and optimize hydrometallurgical processes of battery recycling for commercial application within the country. This could be best achieved through the organizations and agencies like:-

- Departments of Science & Technology
- National Metallurgical Laboratory, Jamshedpur.
- Regional Research Laboratories.
- Indian Bureau of Mines, Nagpur
- Central Pollution Control Board and the State Pollution Control Boards and
- Lead smelting industries like Hindustan Zinc Ltd., Bharat Zinc Ltd. and India Lead Ltd.

1.6 Present Report

The contents of the report have been divided into ten chapters

Chapter-I in the report provides the background of the market survey.

The introduction to the subject and its relevance in the Indian context has been described in Chapter-II.

Chapter-III is on batteries their types, composition, heavy metals (viz lead, mercury and cadmium), the important constituents of batteries, and the related issues.

Chapter – IV deals with sources of lead, mercury and cadmium, their role in the industrial scenario of the world in general and of India in particular. The need of these metals and the role of recycling in meeting the demand have also been discussed.

Since battery scrap fall under the categories of hazardous wastes, the existing legislation on management of hazardous wastes both in India and abroad and further development in this regard has been presented in Chapter-V.

An introduction of various technological options and the modern out-look of changes and modifications in the earlier process due to environmental protection awareness has been described in Chapter-VI.

Chapter-VII deals with the latest types of lead-acid and dry cell batteries. Battery scrap recycling technologies and their techno-economic comparison with a view to select the appropriate technologies routes in the Indian context have been discussed.

Chapter-VIII deals with the various technologies for battery scrap recycling in details, describing their process routes and the various utilities needed to put these technologies into commercial use.

Chapter – IX deals with techno-economic survey of the various technologies.

Chapter-X deals with conclusions, recommendation and action plan.

Supporting documents have been placed in relevant annexures at the end of the report. References of the literature consulted, quoted freely to make the presentation authentic and lucid have been listed and placed after the annexures. A bibliography containing important publications which are considered significant from this study point of view has been given at the end.