Washing carriers and machines using less water
Dyeing, especially of dark colours leaves dye residues coating the steel in the dyeing machine.
These can lead to staining when lighter colours are dyed, so machines need to be periodically cleaned to remove these residues. We aim to minimise the frequency of cleaning by scheduling batches to machines on progressively darker colours, but during 2021 we have been focused on finding ways to reduce the amount of water needed to achieve the cleaning. Work done in our Bangladesh plants have resulted in a process that uses 50% less water, but still results in full cleaning, and this is now being used across the group. Meanwhile in our plant in Shenzhen, China we have successfully implemented the use of ultrasonic cleaning technology for cleaning all the removable parts of the dyeing machines (the thread carriers and spindle caps). This technology is now being implemented in other units. While for this process some capital expenditure is necessary, we have shown the payback is normally attractive.