Case sample of a CT option Control of sulfuric acid use in concentrated latex industry

Working conditions found during audit In latex sedimentation, workers add sulfuric acid to the latex to promote coagulation. They do this by depending on long experience - without measuring. Then they use a stick to stir and mix the acid with latex, and later scoop the coagula floating on the surface. The water remaining is drained into the rubber trap.

Suggested CT option Ensure appropriate consumption of acid used in coagulation, by plotting titration curve of skimmed latex at various amount of ammonia, and add only required amount of acid each time.

Technical feasibility study It is an operational control measure in use. The factory is capable of implementing. There are no other technical limitations.

Economic feasibility study Investment cost 7,000 baht (handheld pH meter and cost for plotting skim latex titration) Service cost 50 baht (sampling skimmed latex for ammonia check) Savings 360 baht (Acid costs saved per sedimentation) Investment payback after sedimentation 23 times (calculated from 7,000/(360-50) times)

Implementation steps

Case sample of a CT option Proper use of a water softener

Working conditions found during assessment Resin is rinsed off the water softener by using 100 kg. of salt in each regenerating cycle. Regeneration takes 15 minutes The softener is used for eight hours before the next regeneration

Suggested CT options Use salt with 10% concentration for cleaning, or about 125 kg. per regenerating cycle. Increase regeneration time to 30 minutes Operational time is increased to 24 hours

Technical feasibility study It is a proper resin washing method, lasting no less than 30 minutes. The factory is capable of implementing such adjustments. There are no other technical limitations.

Economic feasibility study Investment cost None Savings 385 baht/24 hours (salt cost 175 kg./day x 2.2 baht/kg., excluding cost for water, labor and time saved) Payback period Immediate

Work procedure

Samples of different CT options

When cleaning factory floors, sweep off dirt and scraps before hosing down with water Check for leaks in various connections, e.g., pipes for raw, soft and cold water, and repair immediately if leaks are found Ensure that float valves are properly functioning Where possible, use high-pressure nozzle on water hoses

Avoid cleaning by overflow system; counter-flow system is preferable Plan production process so that minimal washing is required Product change should not take place too often Check quality of water used and use appropriate type of water

Insulate hot and cold water pipes and repair the insulation if damaged Consider returning condensate Avoid using steam directly by using indirect heat transfer where applicable Water used to cool machines should be reused

Acid and alkaline should not be dumped after only one use; try to re-use by adding acid or alkaline to obtain required concentration For light, fluffy materials, trap systems should be utilized to prevent loss Install water meter at key points so that loss and production efficiency will be known Avoid using hazardous chemicals

Prepare work manuals and have them available for use Maintain machines in good working condition Check condition of boilers regularly If production is much lower than production capacity, production process should be revised to minimize loss

Air conditioner should be set at an appropriate temperature Lights should be turned off when not in use; use spot lighting where possible Light switches should be positioned throughout different work areas. Replace spent bulbs with energy saving bulbs. Clean light bulbs and reflectors regularly

Summary CT benefits Increased production efficiency Reduced production cost Reduced environmental problems at source Good image Good relations with local community

Summary Factors crucial for sustaining CT Management support Team work Determination Communication Training Incentives

Summary Management role in CT implementation Continuous support for CT activities Involve everyone in the organization in CT activities Incorporate CT into management plan (marketing, production, finance, accounting, personnel and information system

e-mail : ctu@diw.go.th For additional information, contact: Cleaner Technology Unit Tel. 281-2010 Fax 281-7287 e-mail : ctu@diw.go.th