On the Application of Small-Scale Turbines in Industrial Steam Networks

• Main Authors: Ansgar Weickgenannt, Ivan Kantor, François Maréchal, Jürg Schiffmann
• Format: Article
• Language: English
• Published: MDPI AG 2021-05-01
• Series: Energies
• Subjects: industrial steam networks; oil-free; small-scale turbomachinery; process integration; exergy; energy recovery
• Online Access: https://www.mdpi.com/1996-1073/14/11/3149

This study investigates the technical and economic feasibility of replacing throttling valves with smale-scale, oil-free turbomachinery in industrial steam networks. This is done from the perspective of the turbomachine, which has to be integrated into a new or existing process. The considered machines have a power range of <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>P</mi><mo>=</mo><mo>[</mo><mn>0.5</mn><mo>,</mo><mo>…</mo><mo>,</mo><mn>250</mn></mrow></semantics></math></inline-formula> kW] and have been designed using real industrial data from existing processes. Design guidelines are developed, which take into account the thermodynamic process as well as engineering aspects of such a turbomachine. The results suggest that steam conditioning prior to heat exchange could be completed by small expanders to produce mechanical work, reducing exergy destruction and improving site-wide energy efficiency compared to throttling valves. Cost estimates for such machines are presented, which serve as a basis for case-specific investment calculations. The resulting payback times of less than 18 months highlight the economic potential such solutions.