Batches of improvement

Environmental protection and resource efficiency are playing an increasingly important role in the laundry sector. Water and energy should be used as economically as possible. To conserve resources, the international laundry group CWS recently equipped its new location in Brehna/Germany with a new tunnel washer (continuous batch washer) from Jensen.

The new laundry facility for disinfection washing processes is certified in accordance with RAL 992/1-4 in order to avoid spreading pathogens. The areas in which clean and dirty laundry are processed are physically separated and the facility also has locks for personnel and containers. “Due to separation and certification according to RAL standards, the laundry satisfies all the hygienic requirements of the health care sector,” explains Markus Schad, regional managing director cleanrooms and healthcare for Jensen.

In the new Jensen Senking Universal P36 tunnel washer installed for the personal laundry of nursing home residents, a highly flexible batch washer with internal energy and water recovery, laundry is consistently washed in the bath exchange process (in standing baths). The certified wash process is pre-programmed and automatically applied in the process control. Each batch remains in its own bath and receives its individually programmed quantity of detergent, process water temperature and bath level. Consistent blue-white separation with double conduit routing ensures maximum flexibility and optimal water recovery. Large, modular EcoTanks are used as interim storage tanks for drained process water, virtually 100% of which is reused. The FlexRinse process contributes to a further reduction in the consumption of fresh water and is in line with Jensen’s ‘Think Circular’ theme for sustainability as the process is also based on closed loops. The optimal recovery of process water conserves energy and resources while delivering the best wash results.

The new, patented Jensen UVClean system is also installed at CWS Brehna. It prevents the growth of bacteria in double-drum sectors automatically and without using chemicals. It is the most natural, most environmentally friendly and most efficient way to remove germs and bacteria, says Jensen. UVClean also prevents bacteria from becoming resistant to UV radiation – in contrast to chemical methods. The goal of this investment in a new washroom section was 100% automation and 100% sustainability.

Milnor, the inventor of the tunnel washer back in the day has never stopped innovating its concept. The company believes dilution is the key to best performance in these machines and to this end developed a top transfer system A True Top Transfer tunnel washer’s better washing and rinsing quality, and thus higher productivity, results from three features, says ThIerry Lambermont, speaking before the Clean Show in Atlanta last year.

A tunnel washer’s method of transferring goods is critical because it is the way the machine introduces each batch of goods to its next bath (dilution). And as proven, dilution is best executed if the next bath in all subsequent modules has cleaner water.

Top transfer tunnel washers move linen by lifting the goods out of the water, draining the free water, and then sliding the goods into the next compartment. This process happens in one continuous movement that takes just 3,5 seconds. After the transfer, the goods are immediately exposed to cleaner water. Only the water trapped in the goods moves forward, with very little free water. Milnor tunnels leave back approximately half of the total water in each compartment.

In comparison, bottom transfer tunnels transfer by forcing the goods and water forward within its single shell section, along the bottom of the tunnel. Most, if not all, of the water is pushed forward into the next bath. Therefore, instead of a cleaner bath, the goods are exposed to the same dirty water that was in the previous bath while moving forward through counterflow. Additionally, goods remain in the dirty water until the bath is drained and refilled in a double shell portion of a bottom transfer tunnel.

True Top Transfer combines counterflow, or water moving against the direction of the goods, with the perforated top transfer scoop to achieve efficient and effective dilution. With counterflow, a tunnel washer can achieve nearly the same dilution as a washer-extractor gets with one dump and fill cycle. The difference is that while all tunnels employ reuse water, True Top Transfer tunnels utilise counterflow in each module.

Additionally, the perforated top transfer scoop takes True Top Transfer tunnels a step further. The goods change baths upon each transfer. Therefore, True Top Transfer tunnels achieve approximately the equivalent of a second dump and fill and nearly twice the dilution of bottom transfer tunnels within their drain and fill chamber. Milnor’s loading scoop lifts the goods, drains them, and deposits them into cleaner water. But a bottom transfer tunnel sends dirty water into the next compartment within its single shell section along with the goods. Consequently, there is no dilution as the whole compartment moves forward.

Point two, he says, is that there is more room in the cylinder in its True Top Transfer set up which means better and more efficient processing, including chemicals absorption. The third reason for the True Top Transfer tunnel’s enhanced dilution is higher mechanical action, which is illustrated by the wash action in the first compartment of all tunnels. Lift and drop action is greater in a top transfer tunnel washer than virtually all other tunnels.

So, enhanced dilution in a cleaner bath with top transfer compared with bottom transfer, larger cylinder capacity and more intense mechanical action all combine for a better result in a True Top Transfer machine, says Lambermont.

Start press

With only a relatively small investment a solution could be to switch out an old press for a new Kannegiesser PowerPress. For example, says Kannegiesser, at a performance of 1,5 t/h , the steam cost of €/t.70 and the residual moisture reduction by replacing the press from 52% down to 38%, the annual savings at a singleshift operation can be around €60,000 Switching to a more sustainable process is not only beneficial for the bank account, but also for the environment. A classic win-win scenario.

Lavatec’s LAVAPress Ultra 597S 60-bar extraction press, is a prodigious extraction press designed to speed workflow and conserve resources. With the ability to handle 265-pound loads using up to 60- bars of pressure, it processes more linen from a tunnel washer and compresses the time spent on each load before moving to a dryer.

According to Erwin Vanspauwen of CLMTexfinity One of the main savings of energy in a laundry can be achieved by the water extraction press. The more water extracted from the linen, the less energy will be consumed in the finishing process to remove the remainder of the water in the linen. Due to the heavy duty steel frame construction, 200mm thick steel plate without micro-deformations. CLMTexfinity uses, a higher force can be created in the press, It allows the pressure to reach up to 63bar, one of the highest pressures reached so far in water extraction presses.

This high pressure is delivered by a cylinder with a Ram of 410mm diameter, the largest one used in water extraction presses, ensuring less stress to the parts and structure and a longer life.

The CLMTexfinity press stainless steel basket has a thickness of 26mm, avoiding deformations of the basket. Small deformations in the basket will reduce the lifetime of the membrane and reduce the water extraction efficiency. Consequently the basket lifting cylinders are significantly larger than commonly used in the laundry industry. ­