Energy efficiency Heat
Energy efficiency Heat recovery Fig. 2: A functional interconnection and control of several water coolers integrated in the system technology creates undreamt-of potential for the utilisation of the heat bound in the gas This can be done in different ways inside and outside the machine technology. However, the aim is to create an optimum of functional integration, cost-effectiveness and efficiency. This is where the engineering expertise and innovative creativity of RKR’s system solution come into effect. Functional interconnection and control of several water coolers integrated in the system technology creates undreamt-of potential for utilising the heat bound in the gas. Making sensible use of thermal energy As a result of the innovative interconnected system technology, it was possible to feed a heat output of 1,200 kW (1.2 megawatts!) into the customer’s process after one hour, even with two machines operating at partial load. This meant that a large part of the electrical drive energy, which was converted into heat du ring compressed air generation, could be used for temperature control in the production process without having to resort to previously additional energy sources. This enables significant energy savings, improved economic efficiency, increased energy Fig. 3: Master-slave configuration using the example of a compressed air system with connected dryers 22 GREEN EFFICIENT TECHNOLOGIES 2023
Energy efficiency Heat recovery Fig. 4: Machine control and HMI expand the system perspective efficiency of the overall system and, thus, an important contribution to the climate and the CO 2 footprint. Maximum plant performance thanks to customised compressed air solutions The air- or water-cooled compressors supply oil-free and absorption-free compressed air in the pressure range from 4 to 11.5 bar (g) and are designed for volume flows from 166 m³/h to 9,300 m³/h. The modular concept guarantees a high degree of functional adaptability for different drive and control concepts and ensures the greatest flexibility in adapting to the application-specific requirements and customer-specific process conditions, as shown in the application described above. In addition to functionally tailored solutions, customised versions for particularly sound-reduced applications, outdoor installations or heavy-duty container configurations are also used. Scaling up to the automation level Also called: the individual solution is perfectly tailored to the application - whether as a stand-alone solution or in a machine and system network, see application example of a compressed air system with connected dryers in a so-called master-slave configuration. This tailored master-slave control in the system network makes it possible to operate several compressors and dryers in a coordinated manner in one system. Here, there is a master compressor that has control over the control unit and adjusts the output of the slave compressors according to the requirements of the system. The control unit monitors the operating parameters of the compressors, such as pressure and flow, and controls them so that they operate efficiently and reliably. An additional redundant control system provides an additional level of protection against failures in the control system. The combination of a master-slave control with a redundant control further increases the reliability of the system solution, as a failure of one control unit does not lead to a failure of the entire system. In this specific application, communication takes place between the compressors, the respective variable-speed drives via medium-voltage frequency inverters, the dryers and the DCS (Distributed Control System) via PROFINET. PROFINET as a proven industrial communication protocol enables fast and reliable communication between the various components of the entire system. With increasing automation and a more specific collection of operating data/conditions, further perspectives for system monitoring and optimisation arise: scalable system mo- dules with interfaces for remote and/ or local operation and system analysis as well as service logs are available and can be combined with supplementary services as required. Customised system solutions with added value in the customer application With the combination of a machine and system perspective, creative, competent engineering and a proven modular scalable construction kit, RKR, as a specialist for double-stage compressor solutions within AERZEN Group, offers tailored system solutions with added value in the customer application. The competent team supports users in exploiting their previously unused potential. The Author: Lothar Stoll, Managing Director RKR Gebläse und Verdichter GmbH www.rkr.de, www.aerzen.com GREEN EFFICIENT TECHNOLOGIES 2023 23
