1. Improving BSO Services and SME Performance Through Cleaner Production [DATE][SPEAKERS NAMES]

2. Module 3: A closer look at the Cleaner Production process

3. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 3 Virtual Cleaner Production tour  In this module, we take a detailed “virtual tour” of a CP case example  Purpose  Provide overview of the CP process  Introduce CP tools and techniques

4. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 4 “Midland Metals” Enterprise Profile: Based on case study created by the United National Environment Program, Division of Technology, Industry and Economics CASE STUDY country sector ownership established employees revenue Zimbabwe Foundry Family-owned 1998 16 US $65,000

5. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 5 Background: What is a Foundry?  Casting is one of the oldest industrial processes  There are different casting processes. The focus here is: “GREEN SAND” CASTING Midland Metals CASE STUDY A foundry is: a factory that pours molten metal into molds, producing cast metal objects. Some typical cast metal objects: “low tech”“high tech” Turbine blades in jet engines Engine blocks, axles Aluminum pots

6. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 6 Background: SAND-CASTING Sand, mixed with clay binder & water (so it will hold its shape) plus coal dust to improve surface finish Pattern (a copy of the shape you want to produce, made of wood, plastic or metal) Basic materials & equipment for green sand-casting Container of molten metal (filled from furnace) Top and bottom mold forms (made of metal, open at top and bottom) Rammer (tool to compact the sand; often a pressing machine is used) Midland Metals CASE STUDY

7. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 7 Background: SAND-CASTING MOLDING : Sand placed into bottom mold form & compacted MOLDING : Pattern placed into mold A very basic summary of the sand casting process... First of all, mix the sand. 2 1 Midland Metals CASE STUDY THEN

8. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 8 Background: SAND-CASTING MOLDING: Add the top mold form 3 4 MOLDING: Fill top form with compacted sand. A tube or pipe provides a path to pour the metal in Pattern is still inside! Midland Metals CASE STUDY

9. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 9 Background: SAND-CASTING MOLDING: Take the top mold off and remove pattern & pipe or post 5 6 MOLDING: Replace the top mold and fasten securely! Pouring hole In the middle of the sand is a cavity shaped like the pattern! Midland Metals CASE STUDY

10. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 10  Background: SAND-CASTING 7 CASTING: Pour the metal (container is filled from furnace immediately before you are ready to pour) 8 Wait for the metal to cool (minutes to days, depending on the size of the casting) Midland Metals CASE STUDY

11. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 11 Background: SAND-CASTING 8 SHAKE OUT: Break apart the two halves of the mold & take out the part—usually requires vibrating or striking the mold to break apart the sand CLEANING. Sand is cleaned off the part, the “tab” where metal flowed in must be removed. 9 A copy of the pattern has now been made in metal 10 Mold forms are reused 11 Sand is broken up, screened to remove debris and clumps, and sent for remixing Midland Metals CASE STUDY

12. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 12 Background: SAND-CASTING Sand-casting is simple in concept, but demanding in execution. It is a process essential to making basic and advanced products... it is also hazardous and energy-intensive! Midland Metals CASE STUDY

13. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 13 Midland Metals CASE STUDY Midland Metals Enterprise Profile, cont’d: products Production volume Markets Iron mill balls & crushing hammers (used for crushing ore) 25 tons/month (planning 10-fold expansion) Mining sector (mill balls) 3-15cm

14. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 14 Foundry process map Sand (new/old), bentonite*, coal dust, water, energy liquid metal Molding Section Dust, gases, mold forms, used sand Dust, gases, noise, reject mixed sand, surplus sand Dust, gases, surplus sand, noise, rejected molds Energy Gases, organic fumes Patterns, mold forms, sand filling, coatings, energy *Bentonite is a mineral clay. It forms a binding agent when mixed with water. Midland Metals CASE STUDY Sand mixing area Molding section Casting area Shake-out & Cleaning area INPUTS Non-Product OUTPUTS Finished products

15. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 15 Initial CP assessment findings 1.Sand contains significant amount of dust 2.Wind blows sand and dust from stock piles 3.Workers estimate quantities for sand binder and hardener 4.Energy consumption of furnaces higher than normal for similar operations 5.Furnace tap-hole not well sealed after use 6.Liquid metal spills during filling of molds 7.Large number of rejects 8.Sand is lost in each cycle 9.Sand mixing and reclamation very labor intensive Midland Metals CASE STUDY

16. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 16 Material balance for sand mixing Energy - Electricity = 6 MWh SAND MIXING PROCESS (mostly manual) Emissions to the atmosphere - Dust = 30 t Raw materials - New sand = 135 t - Old sand = 540 t - Coal dust = 55 t - Bentonite = 55 t - Water = 40,320 litres Waste - Used sand = 105 t Products - Moulds and cores = 672 tonnes INPUTSOUTPUTS Annual figures Midland Metals CASE STUDY ! only 75% reclamation efficiency (25% of sand in each batch is lost.)

17. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 17 Sand Mixing: Raw materials costs InputQuantity per 50 kg batch (kg) Annual quantity* (kg) Unit cost (US$/kg) Annual Total cost (US$) New Sand10134,4000.022,677 Old Sand40537,600-- Bentonite453,7600.179,027 Coal Dust453,7600.073,673 Water3 litres40,320 litres0.02840 Total16,217 Midland Metals CASE STUDY (*56 batches/day x 240 days/yr) New sand = 17% of raw material costs !

18. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 18 Biggest CP opportunities  Waste of raw material (sand)  During mixing stage  Spillage  Dust  Inefficient use of labor  Manual sand mixing  Manual screening for sand reclamation  RESULT: 4 man-hours required to mix 1 batch Midland Metals CASE STUDY 25% loss = 2000 kg sand per ton product !

19. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 19 Good housekeeping Better process control Equipment modification Input substitution Rapid payback CP opportunities Midland Metals CASE STUDY Cover the new sand278 Implement more thorough inspection, segregation of incoming scrap116 Annual savings (US$) Use sand with low dust content232 Optimize furnace-melting conditions139 Train workers to properly handle and measure sand binder & hardner185 Improvise proper closing mechanism for furnace taphole28 Install goods spouts on melting pots28 Total annual savings: $1005

20. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 20 Capital investment CP opportunity: Mechanical sand reclamation/mixing Hopper Conveyor Belt Mechanical Sand Mixer Shaker table with Screen Molds shaken out (Removes lumps) (Transports sand) (Feeds sand to mixer) Midland Metals CASE STUDY Old system: New system: Mechanical sand reclamation plant Manual sand reclamation & mixing Roller sand mixer + accessories + shipment $8,106 Sand shaker$3,706 Sand screen below the shaker$347 2 x 5 kW motor$926 10 m conveyor belt$694 Other construction material$463 Sand storage hopper$1,158 Installation costs$810 Contingencies$1,621 TOTAL INVESTMENT COST$17,833

21. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 21 NEW sand mixing material balance Energy - Electricity=24MWh Raw materials - New sand = 65 t - Old sand = 610 t - Coal dust = 55 t - Bentonite = 55 t - Water = 40,320 litres Emissions to the atmosphere - Dust = 15 t Waste - Used sand = 50 t was 30 t was 105 t SAND MIXING process (mechanized) was 135 t Increase from 6 MWh Midland Metals CASE STUDY Products - Moulds and cores = 672 tonnes INPUTSOUTPUTS

22. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 22 Profitability analysis: Mechanical sand reclamation/mixing 31.25% saving on labor$3,543 24% saving on raw materials $8,351 Lower overall operating costs* $2,630 Total net savings (per year)$14,525 Payback Period<2 years Net Present Value (@20%, 5 years)$25,606 Internal Rate of Return77% Midland Metals CASE STUDY INVESTMENT COSTSAVINGS (annual) *even with increase in electricity costs $17,833 ANALYSIS Vs.

23. Improving MSME Performance through Cleaner Production. Module 3: A Closer Look at CP. Visit www.encapafrica.org. 23 Benefits of Cleaner Production 1.Improved Profitability Raw material saving of 25% Labour costs cut by 30% Reduced plant and equipment maintenance costs 2.Improved product quality 3.5 to 7 fold increase in production levels (pieces/per day), so total profits increase 5 to 7 fold as well 4.Reduced environmental impact Midland Metals CASE STUDY