Cutting operating costs and saving resources
Goldkronach, December 2017 – Innowo Print is the market leader in the printing of nonwoven materials for hygiene products and supplies all of the well-known manufacturers in the industry worldwide. In order to make more efficient use of resources during production, the print shop has equipped its German site with a thermal exhaust air purification system with heat recovery. The system from Luft- und Thermotechnik Bayreuth GmbH (LTB) saves the manufacturer around EUR 40,000 in heating costs per year. This means the heat exchanger will have paid for itself within just 1.5 years. The company’s plant in Malaysia also uses LTB exhaust air technology to engage in eco-friendly work practices in accordance with European standards. The environmental technology specialist LTB is part of the Dürr Group.
The large number of orders received by Innowo Print, a subsidiary of the Danish company Fibertex Personal Care, meant that its existing exhaust-air purification system was full to capacity. “We needed to extend to ensure that the official emission values were met. We wanted a concept that would link the old and new systems so we could use it to control the total volume of exhaust air,” says Albert Steffen, Managing Director of Innowo Print, in explaining the requirements needed.
The solution consists of an exhaust air purification system from LTB based on regenerative thermal oxidation (RTO). The new system is rated for 15,000 Nm3/h of exhaust air. It requires much less energy during continuous operation than the old exhaust air system from a third-party manufacturer and also features heat recovery. The existing pipe network was modified to enable both systems to be serviced from one manifold. The exhaust air volumes are coordinated by a higher-level control system so that both systems operate in their respective optimum operating conditions. This ensures that the old system is operated as cost-effectively as possible, and the new, more efficient RTO is operated at maximum capacity. Although the existing system had been purchased from another manufacturer, LTB carried out this energy-efficient integration.
Making cost-effective use of energy from exhaust air
The solvents used in the printing process release a large amount of energy during the combustion process, which used to be lost as hot exhaust air through the stack at Innowo Print. “Our goal is to minimize environmental pollution along the entire manufacturing process. Our customers also increasingly want to know how we are making our production more resource-efficient. Therefore the new exhaust air purification system combined with heat recovery is not just logical for us, but also cost-effective,” says Steffen.
Innowo Print will spend much less on heating in the future, since the energy recovered from afterburning through a 600 kW hot water heat exchanger will be used for factory air conditioning. With a heating period of 4,000 hours annually, this will reduce the amount of heat required by an average of 250 kW which will no longer need to be purchased as primary energy. This will result in a savings of around EUR 40,000 per year.
In order to be prepared for further growth, the new system including the heat exchanger was designed from the onset in such a way that the exhaust air capacity could be doubled to 30,000 Nm³/h with little technical effort. The LTB unit is designed so that the system can be easily extended within a few days if necessary. This is much faster and less expensive than building a brand new system.
Service for high operational reliability
The reliable availability of exhaust air purification systems is extremely important for the printing industry. “You need an afterburning system to get an operating license for a printing plant of this size. If this system were to fail, we would no longer be able to operate the print shop and would have to shut down the presses,” spells out Steffen.
Dürr offers a comprehensive service package and worldwide support with service centers close to the customer that are also used by the subsidiary LTB. This was an important factor in Innowo Print’s decision to award the contract. LTB has a service team available to the print shop located in Ilsenburg just two hours away in Goldkronach. As well as maintenance and repairs, the service package also includes performance improvements to the systems. This involves analyzing the data recorded by the systems and making appropriate adjustments to the parameters in order to further optimize operating costs.
Demand for printed nonwovens is also growing in Asia. In order to meet this growing demand, Fibertex, Innowo Print’s parent company, built its own plant in Malaysia. Even though it is not a statutory requirement in the South East Asian country, the print shop was equipped with a RTO rated for 20,000 Nm3/h in order to ensure eco-friendly production in accordance with European standards. The project was designed in Germany by Dürr and supported by their subsidiary in Malaysia.
“Our cooperation with LTB was completely professional and purposeful. Preliminary discussions focused on gathering information in order to identify our requirements. LTB then used this information to come up with competent proposals that enabled us to quickly find the right system for us. The project was also completed very promptly,” says Steffen in summarizing the company’s experiences of the two projects.