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Cleaner Production
that when the annual saving is low with respect to the costs of installation,
the payback period increases. This means it will take longer to recover the
investment made. Some of the cleaner production solutions were imple-
mented with no cost solutions like improving the boiler efficiency but did
produce an annual saving of $2,714 in Edfina and $5,974 in Kaha. The other
measures were meant to be low cost to be economical and technologically
feasible. Most of the solutions have a payback period of around one year so that
the investor reaps a quick return on his investments and continues with
other CP opportunities.

Food sector: Process optimization at a sugar beet
manufacturing facility
The process optimization at a sugar manufacturing facility in Tunisia is a clear
example of the application of a source reduction technique. It employed good
housekeeping and process modification to achieve cleaner production objec-
tives (NCDENR 1997).
The Tunisian cleaner production program started in September 1993 with
the aim of promoting the use of cleaner production practices to improve pro-
ductivity and reduce pollution with an opportunity of financial savings. The
United States Agency for International Development (USAID) funded the
initiative, and currently funding is continued through the United Nations
International Development Organization (UNIDO)/United Nations Environ-
mental Program (UNEP). The program is implemented locally by the “Center
de Production Plus Propre”, CP3.
The assessed facility is a processing plant which produced white sugar
from beets. It started production in June 1983. It employed 658 workers and
operated a maximum of 70 working days during the beet harvesting season.
The remaining days of the year were dedicated to maintenance works. The
total capacity of the plant is 36,000 tons and produced 18,500 tons of white
sugar in 1993.

Process description
The plant initially performs the following processes:

• Beet reception: Beet loads are sampled and analyzed for tare and sugar
content; they are then unloaded and run through preliminary dry clean-
ing to a storage slab before being hydraulically transported through
a cleaning station designed to separate the flow into clean beets, rocks,
beet chips and vegetable matter.
• Beet processing: Beets are brought into the factory for slicing into strips
called cossettes. These cossettes are heated to 85°C for scalding.
• Juice preparation: Juice produced by the diffuser is purified by two
major treatment steps: first and second carbonation before it passes
through ion exchange to remove possible remaining impurities.