Simple and compact low-temperature power cycle

A thermodynamic power cycle system for extracting a flow of heat from a heat source stream and generating mechanical power from the flow of heat by means of a working fluid flowing within a closed-loop cycle, said system comprising:

• means for transferring heat from the heat source stream to the working fluid such that the working fluid warms from a first temperature to a second temperature that is more than 30° F. greater than the critical temperature of the working fluid, wherein the working fluid has a critical temperature more than 40° F. lower than a temperature of the heat source stream and has a normal boiling point less than 32° F.;
• means for expanding the working fluid and converting work of expansion of the working fluid to mechanical power;
• said means for expanding and converting work of expansion also throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat;
• means for cooling to condense and subcool the working fluid after the means for expanding;
• means for returning the working fluid to the means for transferring heat;
• wherein the means for transferring heat, the means for expanding, the means for cooling, and the means for returning the working fluid to the means for transferring heat are the only four means in which energy is removed from or transferred into the working fluid in the form of heat or work;
• said thermodynamic power cycle system further comprising means for redirecting the flow of the working fluid after the working fluid has exited the means for transferring heat to bypass the means for expanding, the means for redirecting the flow containing a means for throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat.

A thermodynamic power cycle system for extracting a flow of heat from a heat source stream and generating mechanical power from the flow of heat by means of a working fluid flowing within a closed-loop cycle, said system comprising:

• means for transferring heat from the heat source stream to the working fluid such that the working fluid warms from a first temperature to a second temperature that is more than 30° F. greater than the critical temperature of the working fluid, wherein the working fluid has a critical temperature more than 40° F. lower than a temperature of the heat source stream and has a normal boiling point less than 32° F.;
• means for expanding the working fluid and converting work of expansion of the working fluid to mechanical power;
• said means for expanding and converting work of expansion also throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat;
• means for cooling to condense and subcool the working fluid after the means for expanding;
• and
• means for returning the working fluid to the means for transferring heat;
• wherein the means for transferring heat, the means for expanding, the means for cooling, and the means for returning the working fluid to the means for transferring heat are the only four means in which energy is removed from or transferred into the working fluid in the form of heat or work, and
• wherein said system further comprises two or more heat source streams, with the thermodynamic power cycle system comprising additional means for transferring heat, each of which means for transferring heat is dedicated to a single heat source stream;
• wherein the working fluid is divided into separate streams, with each of the separate streams of working fluid being dedicated to a separate means for transferring heat;
• and wherein the separate streams of working fluid, after having been heated by transfer of heat from the heat source streams, are combined into a single working fluid stream.

A thermodynamic power cycle system for extracting a flow of heat from a heat source stream and generating mechanical power from the flow of heat by means of a working fluid flowing within a closed-loop cycle, said system comprising:

• means for transferring heat from the heat source stream to the working fluid such that the working fluid warms from a first temperature to a second temperature that is more than 30° F. greater than the critical temperature of the working fluid, wherein the working fluid has a critical temperature more than 40° F. lower than a temperature of the heat source stream and has a normal boiling point less than 39° F.;
• means for expanding the working fluid and converting work of expansion of the working fluid to mechanical power;
• said means for expanding and converting work of expansion also throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat;
• means for cooling to condense and subcool the working fluid after the means for expanding;
• and
• means for returning the working fluid to the means for transferring heat;
• wherein the means for transferring heat, the means for expanding, the means for cooling, and the means for returning the working fluid to the means for transferring heat are the only four means in which energy is removed from or transferred into the working fluid in the form of heat or work, and
• wherein the heat source stream comprises a gas, liquid, solid or mixture thereof;
• said thermodynamic power cycle system further comprising means for increasing the pressure of the heat source stream to restore pressure lost by the heat source stream as it flows through the means for transferring heat.

A thermodynamic power cycle system for extracting a thermodynamic power cycle system for extracting a flow of heat from a heat source stream and generating mechanical power from the flow of heat by means of a working fluid flowing within a closed-loop cycle, said system comprising:

• means for transferring heat from the heat source stream to the working fluid such that the working fluid warms from a first temperature to a second temperature that is more than 30° F. greater than the critical temperature of the working fluid, wherein the working fluid has a critical temperature more than 40° F. lower than a temperature of the heat source stream and has a normal boiling point less than 32° F.;
• means for expanding the working fluid and converting work of expansion of the working fluid to mechanical power;
• said means for expanding and converting work of expansion also throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat;
• means for cooling to condense and subcool the working fluid after the means for expanding;
• and
• means for returning the working fluid to the means for transferring heat;
• wherein the means for transferring heat, the means for expanding, the means for cooling, and the means for returning the working fluid to the means for transferring heat are the only four means in which energy is removed from or transferred into the working fluid in the form of heat or work, and
• wherein the working fluid is sulfur dioxide.

A thermodynamic power cycle system for extracting a flow of heat from a heat source stream and generating mechanical power from the flow of heat by means of a working fluid flowing within a closed-loop cycle, said system comprising:

• means for transferring heat from the heat source stream to the working fluid such that the working fluid warms from a first temperature to a second temperature that is more than 30° F. greater than the critical temperature of the working fluid, wherein the working fluid has a critical temperature more than 40° F. lower than a temperature of the heart source stream and has a normal boiling point less than 32° F.;
• means for expanding the working fluid and converting work of expansion of the working fluid to mechanical power;
• said means for expanding and converting work of expansion also throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat;
• means for cooling to condense and subcool the working fluid after the means for expanding;
• and
• means for returning the working fluid to the means for transferring heat,
• wherein the means for transferring heat, the means for expanding, the means for cooling, and the means for returning the working fluid to the means for transferring heat are the only four means in which energy is removed from or transferred into the working fluid in the form of heat or work, and
• wherein all means of the system except for the means for transferring heat are mounted on one or more portable transportation means.

A thermodynamic power cycle system for extracting a flow of heat from at heat source stream and generating mechanical power from the flow of heat by means of a working fluid flowing within a closed-loop cycle, said system comprising:

• means for transferring heat from the heat source stream to the working fluid such that the working fluid warms from a first temperature to a second temperature that is more than 30° F. greater than the critical temperature of the working fluid, wherein the working fluid has a critical temperature more than 40° F. lower than a temperature of the heat source stream and has a normal boiling point less than 32° F.;
• means for expanding the working fluid and converting work of expansion of the working fluid to mechanical power;
• said means for expanding and converting work of expansion also throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat;
• means for cooling to condense and subcool the working fluid after the means for expanding;
• and
• means for returning the working fluid to the means for transferring heat;
• wherein the means for transferring heat, the means for expanding, the means for cooling, and the means for returning the working fluid to the means for transferring heat are the only four means in which energy is removed from or transferred into the working fluid in the form of heat or work,
• wherein the heat source stream is a gas which contains a condensable vapor, and
• wherein the heat source stream is a stream of pressurized hot gas which has been quenched in water.

A thermodynamic power cycle system for extracting a flow of heat from a heat source stream and generating mechanical power from the flow of heat by means of a working fluid flowing within a closed-loop cycle, said system comprising:

• means for transferring heat from the heat source stream to the working fluid such that the working fluid warms from a first temperature to a second temperature that is more than 30° F. greater than the critical temperature of the working fluid, wherein the working fluid has a critical temperature more than 40° F. lower than a temperature of the heat source stream and has a normal boiling point less than 32° F.;
• means for expanding the working fluid and converting work of expansion of the working fluid to mechanical power;
• said means for expanding and converting work of expansion also throttling the working fluid such that a pressure of the working fluid exceeds the critical pressure of the working fluid by an amount greater than 5% of the critical pressure of the working fluid as the working fluid emerges from the means for transferring heat;
• means for cooling to condense and subcool the working fluid after the means for expanding;
• and
• means for returning the working fluid to the means for transferring heat,
• wherein the means for transferring heat, the means for expanding, the means for cooling, and the means for returning the working fluid to the means for transferring heat are the only four means in which energy is removed from or transferred into the working fluid in the form of heat or work,
• wherein the heat source is generated by a topping cycle, and
• wherein the topping cycle comprises a combustion turbine and wherein the heat source stream is exhaust gas from a combustion turbine.

A thermodynamic process for the production of mechanical power from a heat source stream of gas, liquid, solid, or mixture thereof, said process comprising:

• a. transferring heat from the heat source stream to a working fluid;
• wherein the working fluid is at a pressure more than 5 percent greater than the critical pressure of the working fluid;
• wherein the working fluid is warmed to a temperature more than 30° F. greater than the critical temperature of the working fluid;
• and wherein the working fluid has a critical temperature more than 40° F. lower than the temperature of the heat source stream and the working fluid has a normal boiling point less than 32° F.;
• b. expanding the working fluid to produce mechanical power;
• c. cooling to condense and subcool the working fluid;
• d. pressurizing the working fluid;
• e. directing the flow of the working fluid in a continuous loop through the above described process steps a, b, c, d, in that order, and returning to step a to continue the continuous loop;
• f. process steps a, b, c, and d being the only four process steps in which energy is removed from or transferred into the working fluid in the form of heat or work.