Heat engine system with a supercritical working fluid and processes thereof

摘要

Aspects of the invention disclosed herein generally provide heat engine systems and methods for generating electricity. In one configuration, a heat engine system contains a working fluid circuit having high and low pressure sides and containing a working fluid (e.g., sc-CO2). The system further contains a power turbine configured to convert thermal energy to mechanical energy, a motor-generator configured to convert the mechanical energy into electricity, and a pump configured to circulate the working fluid within the working fluid circuit. The system further contains a heat exchanger configured to transfer thermal energy from a heat source stream to the working fluid, a recuperator configured to transfer thermal energy from the low pressure side to the high pressure side of the working fluid circuit, and a condenser (e.g., air- or fluid-cooled) configured to remove thermal energy from the working fluid within the low pressure side of the working fluid circuit.

主权项

1. A heat engine system for generating electricity, comprising:
a working fluid circuit comprising a working fluid and having a high pressure side and a low pressure side, wherein the working fluid comprises carbon dioxide and at least a portion of the working fluid circuit contains the working fluid in a supercritical state; a power turbine disposed between the high pressure side and the low pressure side of the working fluid circuit, fluidly coupled to and in thermal communication with the working fluid, and configured to convert thermal energy to mechanical energy by a pressure drop in the working fluid flowing between the high and the low pressure sides of the working fluid circuit; a motor-generator coupled to the power turbine and configured to convert the mechanical energy into electrical energy; a pump coupled to the power turbine, fluidly coupled to the low pressure side of the working fluid circuit by a pump inlet configured to receive the working fluid from the low pressure side of the working fluid circuit, fluidly coupled to the high pressure side of the working fluid circuit by a pump outlet configured to release the working fluid into the high pressure side of the working fluid circuit, and configured to circulate and pressurize the working fluid within the working fluid circuit; a heat exchanger fluidly coupled to and in thermal communication with the high pressure side of the working fluid circuit, configured to be fluidly coupled to and in thermal communication with a heat source stream, and configured to transfer thermal energy from the heat source stream to the working fluid; and a recuperator fluidly coupled to a condenser in series on the low pressure side of the working fluid circuit, wherein:
the recuperator is fluidly coupled to the working fluid circuit downstream of the pump and upstream of the heat exchanger on the high pressure side of the working fluid circuit, fluidly coupled to the working fluid circuit downstream of the power turbine and upstream of the condenser on the low pressure side of the working fluid circuit, and configured to transfer thermal energy from the working fluid within the low pressure side to the working fluid within the high pressure side of the working fluid circuit; andthe condenser is fluidly coupled to the working fluid circuit downstream of the recuperator and upstream of the pump on the low pressure side of the working fluid circuit and configured to remove thermal energy from the working fluid within the low pressure side of the working fluid circuit.