INTERNATIONAL CLEANER PRODUCTION INFORMATION CLEARINGHOUSE

CASE STUDY #24
1.   Headline: Reducing heat loss in lead oxide unit
2.   Background: In March 1993, the Energy and Environment
Branch of the United Nations Industrial Development
Organization (UNIDO), in close cooperation with the National
Productivity Council (NPC) and several other industrial
organizations in India, initiated a cleaner production
demonstration project targeting small scale industries (SSIs)
in India.
     The project DESIRE (Demonstration in Small Industries
     for Reducing wastE) began in March 1993. Its objectives
     included:
     - the demonstration of cleaner production opportunities
     and benefits to small-scale industries in India
     - the development of a systematic method for cleaner
     production
     - the identification of obstacles and incentives for
     cleaner production
     - the formulation of cleaner production policies.
     Three sectors:
     - agro-based pulp and paper production
     - textile dyeing and printing
     - pesticides formulation
     were targeted for demonstration projects, as they are
     sources of significant pollution and are primarily made
     up of SSIs.
     Four to six companies in each of the sectors have
     participated as demonstration units in the project.
     Although final results are awaited on DESIRE,
     preliminary data from the participating companies show
     economic and environmental improvements.
     A lead oxide unit, employing a pot type electrical
     furnace, manufactures one ton of lead oxide per day.
     A waste minimization audit at Sagar Surgicals Private
     Ltd found that the radiation heat losses from the side
     walls in the electric furnace was about 1600 KCals/m2
     hour, and from the top, 2400 KCal/m2 hour. Due to there
     losses, the temperature inside the furnace was not
     adequate for obtaining the desired yield and quality of
     lead oxide. Additionally, fuel and power consumption and
     batch process time were high, and the furnace life was
     reduced due to overheating of the shell.
     The lead oxide unit at Sagar Surgicals employs a pot
     type electrical furnace, and manufactures one ton of
     lead oxide per day.
3.   Cleaner Production Principle: Process modification
4.   Description of Cleaner Production Application: The
     cleaner production applications mainly centered around
     process modifications. The furnace design was modified
     and better heat insulating material was used to reduce
     heat loss.
     Enabling technology: The existing insulation of fire
     bricks was replaced by better insulating materials of
     optimum thickness and sequence. A ceramic fibre module
     was added to the top of the furnace, and ceramic fibre
     blankets and insulating bricks were added to both the
     side walls and the top.
5.   Economics:
          Savings                      US $/year
          Fuel consumption                6 600
          Power consumption               3 300
          Yield improvement              19 800
          Capacity improvement             9 900
          Total                        39 600
                                      US $/year
          Capital investment               10 000
          Annual operating costs             5 000
          Net annual savings               34 600
          Payback period                <3 months

6.   Advantages:
     - Specific fuel consumption has been reduced from 80 to
40 liters/batch.
     - Specific power consumption has been reduced from 500 to
400KWh/batch.
     - The cycle time has decreased to 16 hours, from around
20-22 hours.
     - The furnace temperature has increased by 70C to 400C.
     - The percentage of lead oxide in the product has
     increased by around 3% to 31-33%.
     - The estimated increase in the life of the furnace is
4.5 years, from six months to five years.

7.   Constraints: N/A

8.   Contacts:Mr A.K. Asthana
                  Director (Energy Conservation)
                  National Productivity Council
                  Swaroop Nagar
                  Kanpur 208020
                  India
                  Tel: +91 512 255635
                  Fax: +91 842 43634

                  Mr Shisher Kumra, Assistant Director
                  Mr Rajeev Wadhwa, Deputy Director
                  National Productivity Council
                  5-6 Institutional Areas
                  Lodi Road
                  New Delhi 110 003
                  India
                  Tel: +91 11 461 1243
                  Fax: +91 11 461 5002

                  Mr Gudan
                  Sagar Surgicals Private Ltd
                  Panki, Industrial Estate Site 2
                  Panki, Kanpur 208020
                  India

9.                  Keywords:India, metal, lead oxyde, lead,
                    process modification, insulation, DESIRE,
                    energy saving, furnace

10.  Reviewer comments: This case study was originally
     published in the UNEP IE document "Cleaner Production
     Worldwide", Volume II. In the process of preparing the
     document the case study underwent a technical review.