CASE STUDY #47
1. Headline: Treating wastewater in the rubber industry
2. Background: Wastewater produced from the processing of
latex concentrate and the production of Standard Malaysian
Rubber (SMR) is traditionally treated in biological oxidation
ponds. In an increasingly environment-conscious country such as
Malaysia, where the permitted standards for discharge of
effluents into waterways have become very stringent, it is
difficult or impossible for the ponding system to meet
requirements. Furthermore, the traditional system uses a great
deal of costly process water.
Designing a system to treat the effluent to a standard
suitable for reuse or recycling has become an important
and challenging goal. Malaysia has about 80 latex
concentrate and 100 SMR factories, plus numerous rubber
product factories, that produce contaminated wastewater.
The implications of improved treatment techniques for the
preservation of the environment are therefore
considerable.
Golden Hope Plantations Berhad is a leading Malaysian
corporation involved in four business sectors:
plantations, resource-based manufacturing, property
development and overseas operations. Golden Hope has a
strong commitment to the environment and was admitted to
the United Nations Environment Programme Global 500 Roll
of Honour in 1992.
3. Cleaner Production Principle: New technology
4. Description of Cleaner Production Application: The
effluent from an existing oxidation ponding system is further
treated using a new system that produces water of a quality
that not only complies with statutory discharge criteria but
also suitable for reuse. No water is discharged into the
waterways.
Enabling technology: The new wastewater treatment system
is essentially an upward-flow clarification system with
integrated filtration and aeration features that makes use of
both physiochemical and biochemical processes to reduce the
chemical oxygen demand (COD), the biological oxygen demand
(BOD) and the solids content (SS) of the effluent.
The unique features of the system are:
- instant coagulant `penetration' of the `solids barrier',
resulting in ultrashort chemical reaction time, optimum
precipitation efficiency and minimum chemical
requirements;
- dual-stage clarification that maximizes the rate of
clarification and produces highly clarified water;
- closed-loop hydraulic agitation that improves
oxygenation of the flocculating mass;
- cascade aeration following filtration which gives
sparkle to the final effluent and improves the level of
dissolved oxygen in the water; and
- reduction of BOD and COD by as much as 90-95 per cent,
yielding single-digit values-sludge is soaked away in an
earth pit or filter bed.
5. Economics:
ringgits/year
Savings in treatment costs 25 920
Savings in process water 38 880
Net savings 64 800
Capital investment 355 000
Payback period 5.5 years
Where expensive public water supply is used for
processing, recycling offers a net saving of some 60 per cent.
A medium-sized latex concentrate factory can save 180 cubic
meters of water a day.
US$1 = about 2.54 Malaysian ringgits
6. Advantages:
- zero discharge to the waterways
- water reuse conserves an important resource
- the system is relatively inexpensive and easy to
operate.
7. Constraints: N/A
8. Contacts:Messrs Abdul Patah Abdullah and Chang Sin
Golden Hope Agrotech Consultancy Sdn
Bhd
12th floor, Menara PNB
201-A Jalan Tun Razak
P.O. Box 11043
50734 Kuala Lumpur
Malaysia
Tel: +60 3 261 5377
+60 3 261 5548
Fax: +60 3 263 1905
Telex: MA 30844/5
9. Keywords:Malaysia, rubber, new technology, latex,
oxidation pond, COD, BOD, filtration, clarification, water
saving
10. Reviewer comments: This case study was originally
published in the UNEP IE document "Cleaner Production in the
ASIA and Pacific Economic Coorporation (APEC) Region. In the
process of preparing the document the case study underwent a
technical review.