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                    Sustainable Industrial Design and Waste Management
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                            TABLE 2.10
                            Annual Savings from Steam Condensate
                                                     Edfina         Kaha
                                          3
                            Steam saving (m /y)       3,867       10,670
                            Fuel saving (ton/y)         29            74




                Recovery of steam condensate: 2.75 tons of steam are required to produce
                one ton of tomato paste and 3.75 tons of tomato juice. After recovering
                the required heat (latent heat) from the steam, the steam will condense and
                discharge to the sewer or return to the boiler for water and energy conserva-
                tion. By recycling this condensate the savings were achieved as shown in
                Table 2.10.
                Improving boiler efficiency: By reducing the air to fuel ratio to 20–30%
                excess air, boiler efficiencies were improved at the two factories by an average
                of 3% resulting in fuel savings. Fuel savings were 85 ton/year for Edfina and
                77 ton/year for Kaha.


                Water savings measures
                Concerning the water saving achieved in Edfina factory, the following meas-
                ures were implemented.

                Installation of water meters: Water meters were installed in 13 different
                locations to monitor water consumption. Monitoring is one of the very
                important tools for cleaner production to measure the consumption before
                and after modification to be able to calculate the amount of savings.

                Installation of hose nozzles: A huge amount of water was needed to clean
                the tanks and wash the floors in the tomato paste section. On/off spray
                nozzles were fitted to control the water consumption. A water saving of
                       3
                9,000 m /y was achieved.
                Improving the water collection system on the juice line: The cooling water
                from the juice line was collected in a tank to be recycled. This tank was
                smaller than the flow of water resulting in overflow. A larger tank with a
                                                                                 3
                new water pump was installed resulting in annual savings of 24,000 m /y.

                Installation of cooling tower for the bottled juice line: Juice bottles were
                sterilized at 90°C then cooled by water in an open cycle. A cooling tower
                was installed to recover and recycle the cooling water in a closed cycle.
                                         3
                A water saving of 86,400 m /y was achieved.
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