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Sustainable Industrial Design and Waste Management
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when the ranges were not in use. This excess consumption can be
eliminated by the installation of shut-off valves at different con-
trol points to eliminate the waste of water, steam, and chemicals.
– Recycling of final washing water in the bleaching ranges (on-site
recycling and process change): In the Brugman and Gaston County
bleaching ranges, the final clean wash water coming from the bleach-
ing stage can be reused in another, earlier washing stage for washing
after scouring. In each of these two ranges, the final washing unit
has been connected to the washing unit for the scouring process.
This required the installation of pipelines equipped with pumps.

Cost/benefit analysis
Throughout industry, cleaner production and environmental protection mea-
sures can offer real financial benefits in terms of:

• Reduced raw materials consumption.
• Waste minimization.
• Reuse or recycling of in-plant materials.

Implementing these measures will also result in reducing environmental pol-
lution load such that discharge consent was set within the limits of the law.
The benefits achieved in this factory reflect the potential of the importance
and power of CP techniques. A summary of CP techniques used in this fac-
tory are presented below:

• Good housekeeping, which resulted in the preservation of expensive
dyestuffs.
• Input material change, which resulted in: (a) savings in process chem-
icals, (b) reducing rates of water consumption, (c) optimizing energy
consumption, (d) reducing wastewater loads, and (e) improving opera-
tion and productivity.
• Better process control, which resulted in water savings, energy savings,
and wastewater treatment savings.

The significance of these benefits manifests itself in the cost/benefit analy-
sis shown in Table 2.31.
The benefits and achievements in this case study can be summarized
as follows:

• Water consumption has dropped by 20%.
• Thermal energy consumption has dropped by 5%.
• Boiler fuel consumption has decreased by 5%.
• Wastewater volume has decreased by 20%.
• Chemicals and dyestuff costs have dropped by 5%.