The chemical sector’s high energy consumption is a well-known challenge, and Xentrys Leuna Gmbh, a prominent Polyamide 6 manufacturer in Leuna, Germany, is no exception. Driven to significantly reduce their energy expenditure, Xentrys Leuna GmbH implemented an innovative temperature control solution in their reactors, utilizing thermal oil heaters from HTT Energy GmbH. This strategic move has yielded remarkable results, cutting their energy costs in half.
Xentrys Leuna GmbH’s production of Polyamide 6 relies on four reactors operating continuously at 250 to 270° Celsius, processing 140 to 150 tonnes daily. Previously, each reactor was individually heated by an electric heater. To enhance efficiency, Xentrys Leuna GmbH partnered with HTT Energy GmbH to replace the electric heating system with a gas-fired thermal oil unit, effectively rendering the older system redundant.
Image: Production engineer Marcus Weber from Xentrys Leuna GmbH and HTT sales manager Thomas Stieber are pictured at the Polyamide 6 production facility in Leuna, highlighting the energy efficiency benefits of the HTT thermal oil heater featuring a duoblock burner and air preheater.
The initial 1,250 kW HTT unit, operational from September 2010 to May 2011, demonstrated an impressive overall efficiency of 92%. This was achieved through the integration of an air preheater (LUVO) and speed regulators for the combustion air blower, technologies provided by HTT Energy GmbH, specialists in thermal process solutions. The financial impact was substantial: primary energy consumption costs plummeted from EUR 700,000 to EUR 350,000.
Marcus Weber, Production Engineer at Xentrys Leuna GmbH, stated, “The project’s amortization period was less than a year, even accounting for supplementary building and infrastructure expenses like pipeline construction.” Encouraged by these results, Xentrys Leuna GmbH is expanding its production capabilities and installing a second 1,250 kW HTT heating unit with similar advanced features. This unit will manage the temperature control for two additional reactors, designed for maximum redundancy with the existing system. In case of a thermal oil heater shutdown, the operational heater will support the new reactors, while the existing electric heaters can provide backup heat to the older reactors.
Implementing this seemingly straightforward solution required meticulous engineering, including the procedural integration of expansion tanks across all four production lines. The existing single units were converted into secondary circuits using control valves. Furthermore, pressure limits for heat exchangers in the reactors necessitated careful consideration of pressure losses within each unit.
By Spring 2012, all six reactors at Xentrys Leuna GmbH were planned to be operating with HTT thermal oil technology. This transition ensures long-term energy cost savings and complete operational redundancy, guaranteeing 100% plant availability. The rapid amortization time of this investment presents a compelling case for energy-conscious decision-makers in the chemical industry and beyond looking to optimize their operational costs and enhance energy efficiency.
About HTT energy GmbH
Since 1967, HTT Energy GmbH, based in Herford, Germany, has been a leader in process heat recovery using thermal oil technology. HTT systems are renowned for delivering precise temperature control, ranging from -120°C to +400°C, and power outputs from 3 to 30,000 kW. With over 11,000 systems delivered globally, HTT is committed to providing reliable, consistent, efficient, and environmentally responsible thermal process solutions.
