Gas burns brightly28 September 2020
Gas operated equipment is getting some good press lately. Kathy Bowry catches up on some current dryer developments
The postponement of Texcare 2020 to the end of 2021 has rather hamstrung a delve into the new heavy duty dryer products we planned for this issue which would have been a chance to review what would have been on show in June. Many players have told us they will be saving their launches until then, and in the case of the USA, until the Clean Show in Atlanta next year in June. Nevertheless, there is enough out there for us to mull over.
According to Richard Neale in June’s Material Solutions, steam may not be the way of the future as he says a large proportion of new builds and revamps are now using distributed energy systems instead of steam and saving a significant chunk of investment capital in the process. “One big attraction of the move to distributed heating for the dryers and ironers is the ability of the laundry manager to operate part of the laundry without having to start up a central boiler and run this (inefficiently) at reduced output for, say, an evening shift, which is just washing and drying towels.”
He points out that direct gas firing has now become the favoured mechanism for heating tumble dryers and it is steadily gaining ground in the proportion of new ironers that use it. In the gas-heated tumble dryer, all of the products of combustion flow into the dryer airstream, so there is none of the flue gas loss found in the steam boiler (where some 20% of input heat energy is lost to the chimney). The difference becomes even more stark when the heat actually released from the highpressure steam is taken into account. Only the latent heat portion of the energy in the steam is released in the dryer heater battery, leaving typically 10 - 17% in the liquid condensate to be returned to the boiler house via the condensate main (unless the flash steam associated with this is vented to atmosphere, in which case less than half of this heat is actually recovered for re-use).
Jensen was in the vanguard of gas operated machinery, namely dryers for more than thirty years and ironers since this century. Also tunnel washers are available with gas heating, representing the latest step in the development of gas-heated equipment. However, the move to gas from steam was not global and steam has continued to dominate the laundry industry in the developing laundry markets in Asia, South America, and so on. Jensen believes this may now change, as value-engineered gas-heated solutions are offered as an alternative to high-end products.
Unlike steam, gas heated equipment has the heating source right where it needs to be, at the machine. Properly insulated gasheated equipment maintains temperatures, so they can quickly and efficiently heat up in the morning. When you operate individual machines, you use only the required energy for the specific equipment in production. In short, losing less heat energy which means using less heat energy to do the job—making gas heating good for the bottom line as well as the environment.
Gas-heated equipment is available from both ranges of the Jensen-Group, the high-tech Jensen branded machines and the value-engineered machines under the Alpha by Jensen brand.
Higher temperatures and better temperature control
Burning natural gas can replace steam as the heat source in dryers and ironers. It is a hotter heat source, and because you can change the flow speed of gas to increase or decrease the flame size, gas also allows for better and more precise temperature control.
In the USA, Rick Taft is nearly ready to turn the switch on new, more efficient Lavatec equipment at Textile Care Services, his commercial laundry operation on Salt Lake City’s south side. He has just taken possession of a spanking new Lavaspeed LP572 press and LT60 14-compartment bottom transfer tunnel which he has paired with other new equipment that he expects will to make his facility even more efficient. The tunnel will be connected to six Lavatec TT745, 292-pound capacity natural gas dryers, a press discharge conveyor and discharge conveyor system, and a two-tiered shuttle system. All of it will be controlled by Lavatec’s osLaundry management system.
Lavatec’s dryer technology with its infrared sensors has improved drying times by up to 15%. The dryer’s line burner system covers the entire drum, and this provides higher throughput, reduced gas consumption and the elimination of overdrying.
Reductions in electrical, gas and water usage costs are expected from the decreased energy requirements. The TT745 dryers are equipped with infrared technology that determines when the linen is dry, thereby reducing dryer times and energy consumption. osLaundry is a platform and technology independent software program that provides operators with quicker realtime information, allowing them to make adjustments to daily production data in a matter of seconds or minutes instead of hourly.
“We looked at equipment from other manufacturers but we’ve had a great 30- year run and Lavatec has always taken good care of us. They are a very good company with good people,” says Taft. “I can’t wait to turn on the new equipment. It sets us up with our healthcare customers in Utah for the next 10 or 20 years.”
Lavatec has also set major washroom equipment for the new Metro Detroit Area Hospital Services laundry. This new stateof- the-art laundry became operational in the spring.
The new 12-compartment, 220-pound tunnels, paired with Lavatec’s new Lavaspeed presses, will feed 16 Lavatec TT745G natural gas dryers. The dryers will be loaded by an overhead monorail system onto eight conveyers that can send wet goods in either direction for loading to the next available dryer. The dryers are unloaded by conveyors that transfer the loads to a monorail system for transport to the finishing side of the plant.
Stahl is supplying dryers with an integrated plate heat exchanger. Its dryers also benefit from additional insulation and direct drive system, which removes the limitations of an ordinary mechanical drive.
Meanwhile, the ED900 and ED1250 dryers have been a successful addition to the Girbau range of Eco Dryers since their launch 18 months ago and LCN looked at them in Tony Vince’s OPL dryers update in June. However, it is well worth looking at them again in this feature which is dedicated to the heavier end of the market. Girbau marketing manager in the UK, Jo Emmerson explains: “Since their launch, the ED1250 model has been popular in large on-premise laundries where precise control and energy efficiency is key. In addition to appealing to smaller commercial laundries for their competitive price and flexibility, multiple units have been installed within laundries in HM Prisons and since the outbreak of Covid-19 we’ve had a marked interest from the NHS with several machines being installed in hospital laundries in the past three months.”
In summary, the ED900 has a 900-litre drum and a 45kg capacity while its larger sibling, the ED1250, has a 1250-litre drum a 62.5 kg capacity. Both are available with gas, electric and steam heating options.
Emmerson says they have proved popular for their efficiency and that “reduced consumption and drying times are appealing to customers requiring any size of dryer, but the benefits are even more noticeable on these larger units”. She says efficiencies are delivered because of a “long list of industry leading features” which include the modulation of gas heating as standard. Different burners can be activated separately for increased efficiency and better energy management for all types of laundry. While the steam heated ED900 and ED1250 models feature a steel heat exchanger to facilitate the use of high-pressure steam and are supplied with a cooling trap for optimal efficiency and better linen finishing.
A second inverter on the fan motor of these new models provides improved modulation of the airflow allowing users to adjust the dryers for different types of exhaust installations. This feature also makes it possible to adjust the cycle of the program to obtain better results according to the load.
PRO multiphase programming is available for professional and advanced users and allows temperature, rotation speed and heat intensity of each drying phase to be tailored to exact requirements of load. Switching to EASY mode provides simple and easy-to- use controls for basic needs. And the controls are really simple and intuitive.
Gently Does It
Stahl Wäschereimaschinen, manufacturer of commercial laundry machine technology, unveiled its latest product, the TS 1300 drying cabinet, in April.
“The TS 1300 can be used for a wide range of applications,” says Sebastian Hatz, Stahl’s sales manager for Germany, Austria and Switzerland. “It is ideally suited for all applications where laundry is to be dried particularly gently. The mechanical stress on the laundry caused by the rotary movements of a dryer is completely avoided here.”
Such applications include fire brigades, as well as hotels, sports clubs, water sports facilities (for example, wetsuits or life jackets) or craft businesses (such as landscape gardeners and construction companies with wet work clothes or wet work shoes).
In order that a maximum number of customers can use the practical drying cabinet, the TS 1300 has been designed to be extremely flexible. It requires a 230 V power connection and a maximum of 3 kWh power consumption.
Thanks to the condensation drying, exhaust air to the outside is not necessary and the humidity in the room is not increased.
The three temperature levels (40, 60 and 74C) enable the particularly gentle drying of fire brigade clothing, breathing masks, helmets, gloves, boots, equestrian sports articles (such as horse blankets, sweat blankets), ski clothing, work clothes, shoes, bathrobes, life jackets or wetsuits.
As an option, the TS 1300 drying cabinet can be equipped with an ozone lamp, which ensures hygienic drying. Due to the small and harmless quantities of ozone, a reduction of germs and odours is achieved during the drying process.
The flexible applicability is also shown by the equipment options of the drying cabinet. Numerous different plug-in brackets can be attached in a few simple steps and removed again without tools. Thanks to its modular design, the TS 1300 can be configured exactly to the desired requirements.
The TS 1300 drying cabinet is also available for testing in addition to the company’s other commercial laundry machines at Stahl’s showroom in Sindelfingen.