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                TABLE 2.11                                      Cleaner Production  37
                Energy Savings – Cost/Benefits, Edfina Company

                Action                      Heavy oil  Costs of     Annual    Projected
                                            savings    installation  savings  payback
                                            (ton/y)    ($)          ($)       (months)
                Insulation of steam pipes       440       21,792     14,049      19
                Replacement/Installation of     111        2,452      3,544       9
                  leaking steam traps
                Replacement of leaking steam     86        8,244      2,746      36
                  valves
                Installation of pressure        294        7,642      9,387      10
                  regulators
                Recovery of steam condensate     29        5,821      1,589      44
                Improved boiler efficiency        85           0       2,714       0
                TOTAL                         1,045       45,952     34,029      17




                CP techniques implemented
                From the above analysis we can classify the modifications achieved in both
                factories as:

                     • Good housekeeping: Leakages were repaired by fixing or replacing
                       defective valves and steam traps. Water overflow and spillages were
                       avoided.
                     • Technology change: By installing a cooling tower for the bottled juice
                       line associated with collecting sump, pumps and piping instead of using
                       water for cooling in an open cycle. Part of the process was changed
                       and a new technology was used.
                     • Better process control: By controlling the steam flow by installing a
                       temperature controller on the sterilizer and using a larger tank to avoid
                       overflow and insulating the bare steam pipes to avoid heat losses
                       and reducing the air fuel ratio to improve boiler efficiency.
                     • On-site recycling: By recycling the condensate resulting from the
                       tomato paste process as well as recycling the cooling water in the
                       bottled juice line.

                Cost/benefit analysis
                The cleaner production solutions proved to be very effective from the techni-
                cal and environmental points of view. The cost/benefit analysis is summarized
                in Tables 2.11, 2.12 and 2.13. The payback period calculated in all case stud-
                ies is called the “projected payback period” because it is based on invest-
                ments and savings only without taking into consideration the running cost.
                This is due to the fact that the factory is operating with all necessary staff
                and infrastructure. The annual savings for energy are based on fuel savings.
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