Steam is the lifeblood of all laundries and dry cleaners. If they succeed in saving energy in steam generation and operating more sustainably, this not only benefits their profitability but also the environment. The good news: There’s still potential! The magic word is: pressure degassing. Here we explain what it means and how the Siegen-based company Textilservice Petri GmbH can save gas, water, and chemicals with well-designed systems, good advice, and the correct settings.
What is pressure degassing and what does it do?
Everyone knows: Water is involved in steam generation. What is less well known is that the quality of the water in a steam boiler is largely determined by effective degassing. Depending on the pressure and temperature, the boiler water in steam generators contains varying amounts of different gases, such as oxygen or carbon dioxide. These gases are not particularly compatible with metals. Oxygen has an oxidizing effect. Carbon dioxide can even be aggressive when it comes into contact with metal. In other words, it is important to vent the gases to the outside.
To avert the risk of damage to piping systems and system components, we at JUMAG use pressure degassing as an effective method. Steam, as we know, generates pressure. This pressure and the temperature are selected so that the gases dissolved in the water can be almost completely degassed and vented to the outside.
How JUMAG steam generators save energy – thanks to pressure degassing
In the feedwater tank of JUMAG steam generators, the pressure is at best constant at around 0.3 bar – even when the condensate flows back. This already saves energy that would otherwise be required to restore the pressure after a release of pressure. Calculated over the course of a year and the service life of the unit, this translates into quite significant savings. The higher the temperatures – and we’re talking about 107 degrees Celsius – the fewer gases such as oxygen and carbon dioxide are in the boiler. They are expelled. “This way, we remove almost all of the gases from the water and hardly require any dosing chemicals. And the less we use, the lower the operating costs,” explains Andreas Kohl, Managing Director of JUMAG. And because the better-treated water no longer contains as much dosing chemicals and therefore salts, the boiler is protected. Depending on the condensate return flow, steam demand, and hours of use, the number of blowdown intervals can be reduced, saving water—and thus the energy costs that would otherwise be required to heat the fresh water. A true chain reaction that definitely benefits the environment. Furthermore, don’t forget that dosing chemicals can be expensive. The less you need, the more you save, and the better for the environment at the same time.
What other savings can be achieved with steam generation?
Textile Service Example
Textile Service Petri GmbH from Siegen is a broadly positioned laundry and dry cleaning company. It processes almost all of its textiles in-house. “Our main focus is on hotel and restaurant laundry,” reports Managing Director Dirk Petri. When their old steam boiler, a so-called shell boiler, became outdated, they looked for an alternative. “We were always worried that spare parts would no longer be available,” Petri recalls. “Without steam, we couldn’t produce, and thus our ability to deliver to our customers was latently at risk. We had to and wanted to prevent that!” In addition, the old steam boiler was not easy to operate, so only selected employees could open it during a long warm-up phase. Even back then, they were also concerned with the goal of saving energy, which proved to be a very forward-looking decision.
The laundry and dry cleaning company opted for two Jumag DG 560 boilers in a compact modular design, so the entire system was supplied by Jumag.
“With two boilers, one is always running. This allows us to produce continuously and has ensured production reliability in this area. Furthermore, our morning workload has been reduced almost to zero, and we gain about 20 minutes per day that we can use for other purposes,” Petri is pleased to say.
“Thanks to Jumag’s complete solution, our project effort was significantly lower. Energy recovery and thus internal amortization were also important to us, which has become an even more significant advantage these days,” reports Dirk Petri. Steam generation is a complex topic. And since it involves a cycle—from water to steam and back to condensate—there are various adjustments that can be made to influence gas consumption when operating the steam boilers. Petri definitely benefits from energy savings, but he regrets not being able to provide any concrete figures. His company has experienced very different laundry volumes due to the coronavirus pandemic. In addition, additional machines and modified processes also impact energy consumption. But he can still make one statement: “Thanks to the Jumag system, we save about 5% compared to before.” This not only saves money, but also benefits the environment.
