Thermodynamic study of an improved MATIANT cycle with stream split and recompression

In this paper, a modified cycle layout of the MATIANT cycle with zero emission is proposed. The proposed cycle includes three changes: the reheat process is eliminated; stream split and recompression is added; the compressor is replaced by a seven-stage one. These modifications are introduced to achieve a more balanced thermal match of the recuperator and to lower the compression power. The merit of the proposed layout is that it lowers the recuperator's hot end average temperature by about 150 °C and improves its thermal match. The technical requirement of the recuperator caused by the high hot end temperature is lowered. Another advantage lies in the simple cycle layout by eliminating the reheat process. Key cycle variables are studied in a sensitivity analysis to understand their influence on cycle performance, followed by a full variable optimization. The optimized net efficiency of the proposed cycle can reach 45.3%, which is only 0.35% lower than that of the MATIANT cycle. By updating the component efficiencies and constrains to a more modern level, the efficiency can reach 48.63%, which further proves the potential of the proposed cycle.