Concept of a "capture ready" combined heat and power plant

In case of the CHP plants with backpressure turbines and auxiliary condensing units, there is no possibility of an additional steam extraction for CO₂ chemical sequestration. This is due to the fact that those turbines are designed to operate in conditions where the mass flow rate directed to district heating heat exchangers varies from 0 to 90 percent. Such plants require an additional heat source to be installed to cover the heat consumption of the CO₂ sorbent regeneration system. It is possible to build an additional power unit with a backpressure turbine to heat the sorbent up. However one must consider high costs of such an operation and must provide additional space for the installation. The paper presents an analysis of a CHP (Combined Heat and Power) plant with the increased steam flow rate by the amount needed for the sequestration process. Advantages of this solution would be an increased efficiency through increased blade length and higher heat power until integration with CO₂ sequestration plant. Two variants are analyzed, one with a single lowpressure unit, second with two parallel connected LP units. In the second case, a possibility of removing one of the LP parts after integration with CO₂ installation. A parametric study of the units efficiency as a function of sorbents energy consumption ratio is carried out.