34 PROJECT
The giant tunnel batch washer has eight compartments , each responsible for different parts of the wash . Effectively , the machine can wash 400kg with the same amount of water that the hospital currently uses for one wash , and it can do the wash in just under 26 minutes .
The entire system was custom designed and built specifically for Edenvale Hospital , with the components coming from Belgium while design was taken care of in Belgium and Germany . “ Logistics and manufacturing time was really our biggest challenge ,” says Habib . However , once the parts landed in South Africa , it was all systems go for the Joint venture .
The linen starts off on a conveyer belt which has a built-in scale that measures it out into 50kg batches . They then travel along into a shoot that opens into the tunnel washer itself . Water and detergent are added to the wash , and while in the machine , the linen travels through the eight chambers as a screw conveyer with a 1.4m diameter oscillates as it cleans . Each oscillation lasts for two minutes . When the linen is done , the corkscrew shaped oscillator takes a full rotation to push the linen out . It is a continuous washing system .
The system also allows for the recycling of water . The water used in the rinsing and softening process is fed back into the three washing processes . Water from the first three batches – the washing process – is then disposed of down a waste drain . This aids the continuous washing system – keeping the machine constantly cleaning linen .
The conveyer belt .
The water used to clean the laundry is heated to between 85 and 90 ° C . This is to ensure that the laundry is both cleaned and sterilised .
Once the excess water is squeezed out of the linen by a pneumatic press , the linen is then placed on a hydraulic ramp and fed into one of three drying machines . These dryers work on steam , reaching temperatures of up to 170 ° C for around 15 minutes . Again , these high temperatures aid in sterilising the linen . Excess steam is released through exhaust air stacks that release the steam out into the open air .
The dryers are equipped with lint filters that trap any fluff that comes off the linen . These are pulled out of the dryers via a vacuum system . From here , the linen is taken to a Dapauw ironing station that takes the sheets through a set of rollers where they are ironed .
“ This whole system is fully automated ,” says Habib , “ however we will still need to train and upskill operators to take care of some of the tasks .” The laundry runs in two shifts , with a total of three operators per shift on the CBW and a total of five people per shift on the dryer line .
Ultimately , the installation will ensure that water is saved . The steam driven set up will also aid in the efficiency of the laundry , allowing for the linen from other hospitals to be more easily accommodated . PA
“ Logistics and manufacturing time was really our biggest challenge ”
A portion of the pipe configuration .
www . plumbingafrica . co . za @ plumbingonline @ plumbingonline @ PlumbingAfricaOnline January 2024 Volume 29 I Number 11