US20040237526A1

US20040237526A1 - L & N cycle for hydrogen, electricity, & desalinated seawater

Info

Publication number: US20040237526A1
Application number: US10/445,339
Authority: US
Inventors: William Strobl; Joe Holland
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-05-27
Filing date: 2003-05-27
Publication date: 2004-12-02

Abstract

The L & N Cyde combines a single heat source with several different cycles into one unique system that takes maximum advantage of the heat available. The cycles/systems included are 1) a chemo-thermal process to convert water into oxygen and hydrogen, 2) a modified Regenerative Brayton cycle to produce electricity, 3) a thermal flash distillation desalination cycle 4) a reverse osmosis desalination cycle, and 5) ion-exchange mineral extraction system. The heat source will supply a temperature of about 900° C. to 1,000° C. to the chemo-thermal furnace for that process. The hot products of the chemo-thermal water conversion process (oxygen and hydrogen) pass through different heat exchangers to supply heat to the other cycles. In this manner the oxygen and hydrogen proceed through their first cooling step. The hot hydrogen heat exchanger supplies heat to the fluid in the Regenerative Brayton cycle to produce the electricity. The hot oxygen heat exchanger supplies the heat to convert the seawater to steam to extract the salt. The L & N Cycle provides the United States with the economics to allow the success of a hydrogen economy, provide independence from foreign oil, and advert our electricity and fresh water crisis.

Description

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

The Federal government did not directly sponsor any research or development for the invention of the L & N Cycle. However, most of the elements of the L & N Cycle have had research or development sponsored by different agencies of the Federal Government. The L & N Cycle utility invention combines a single nuclear and/or solar heat source with suite of integrated state-of-the-art processes for production of hydrogen, electricity, oxygen, salt, extractible minerals, low grade process heat (warm brine at −100 degrees F.) and desalinated seawater in a manner not considered in past designs. Hence, the invention significantly reduces the cost of producing hydrogen, electricity, and desalinated seawater.

BACKGROUND OF THE INVENTION

Our country is facing three separate crisis situations with oil, power, and water resources. The current electrical power crisis in California has stirred interest in new ways to produce and distribute electricity. Solar power is a clean method to produce electricity but independently it cannot compete with natural gas and coal power plants. Nuclear reactor power plants can compete with natural gas and coal, but if the cost of disposing nuclear waste is included, they may not be competitive. The L & N Cycle will improve economics of these processes and aid in reducing dependence on natural gas.

Moving in the direction of a hydrogen economy will reduce our dependence on foreign oil. Hydrogen is required by 1) the oil industry to improve extraction of clean gasoline from heavy crude oil, 2) the automobile industry for fuel cells, 3) making fertilizer, and 4) many chemical processes. Oil refineries use hydrogen to make gasoline. Crude oil requires hydrogen to refine it into gasoline. Using very heavy crude oil with more hydrogen can provide clean gasoline. Low cost non-fossil hydrogen will also reduce the price of gasoline to the public. Today the majority of hydrogen is produced from natural gas, and therefore is dependent on natural gas prices. Since a majority of the electrical power plants in California use natural gas, their electrical power crisis caused a significant increase in natural gas prices and hence an increase in the cost of hydrogen. The higher cost of hydrogen was passed on to the public through higher gasoline prices. Developing a non-fossil method to produce hydrogen will reduce our dependence on foreign oil and gas. The L & N Cycle will improve the economics of these processes and aid in reducing dependence on foreign oil and natural gas.

Our country is also facing a fresh water crisis. Texas water conservationists predict that Texas will run out of fresh water in 10 years. California is already in a water conservation mode. The population of California is predicted to double in the next 50 years and will need an alternate source for water. Just as the renewable electrical power and non-fossil hydrogen production processes independently are expensive, so is desalination of water. If we can devise an economical method to desalinate seawater we could advert the fresh water crisis. The L & N Cycle will improve the economics of desalination of seawater.

The L & N Cycle has application in our hydrogen economy, electricity crisis and fresh water crisis. Combining a chemo-thermal hydrogen production cycle, an electric power production cycle and a water desalination cycle into one system, sharing one heat source, will provide the economics to allow each product to be competitive in their respective markets. The L & N Cycle will allow recovery of the upfront capital required for implementation and the plant operating cost from three different industries oil, Power, and Water. This patent application is for the unique integration of several independent cycles into one system that maximizes the use of the thermal capability from a single heat source. The L & N Cycle is independent of the heat source.

BRIEF SUMMARY OF THE INVENTION

The L & N Cycle is a system that will produce hydrogen, generate electricity, provide process heat and steam, support mineral extraction via ion-exchange, desalinate seawater via reverse osmosis and/or flash distillation and produce warm brine appropriate for use in domestic heating and cooling using a single heat source coupled to an integrated thermal power/pump cycle. The L & N Cycle combines several different cycles into one unique system that takes maximum advantage of the heat available. The cycles/systems included are 1) a chemo-thermal process to convert water into oxygen and hydrogen, 2) a modified Regenerative Brayton cycle, 3) a thermal flash distillation desalination cycle 4) a reverse osmosis desalination cycle, and 5) ion-exchange mineral extraction system. The heat source will supply a temperature of about 900° C. to 1,000° C. to the chemo-thermal furnace for that process. The hot products of the chemo-thermal water conversion process (oxygen and hydrogen) pass through different heat exchangers to supply heat to the other cycles. In this manner the oxygen and hydrogen proceed through their first cooling step. The hot hydrogen heat exchanger supplies heat to the fluid in the Regenerative Brayton cycle to produce the electricity. The hot oxygen heat exchanger supplies the heat to convert the seawater to steam to extract the salt.

DETAILED DESCRIPTION OF THE INVENTION

The L & N Cycle combines multiple state-of-the-art cycles to employ one heat source. The first cycle will produce hydrogen and oxygen from a chemo-thermal reaction. There are a few different chemo-thermal processes to produce hydrogen. A 600 MWt heat source heats the chemo-thermal furnace to about 900° C. to 1000°C. Water and various chemicals are introduced resulting in oxygen and hydrogen. At this point hydrogen would be cooled and transferred into the current hydrogen pipelines. The University of California, Texas A & M, and others are developing this process. Instead of going directly to the hydrogen pipeline, the L & N Cycle would divert the hot hydrogen to pass through a heat exchanger to transfer its heat to the fluid in a Brayton or Regenerative cycle to produce electricity. The hydrogen would exit the heat exchanger cooled to the entering temperature of the Brayton or Regenerative cycle fluid. The hydrogen would then pass to the hydrogen pipelines. The heat source for the modified Brayton or Regenerative cycle is derived from the above heat exchanger. The electrical power cycle can be an open loop or closed loop cycle. The attached drawing illustrates the L & N Cycle with a closed loop Brayton cycle using an inert gas such as helium in the turbo-compressor. A thermal balance will determine the use of a modified Brayton cycle or a Regenerative cycle. The cycle consists of a turbo-compressor, alternator, and a heat exchanger. With a 600 MWt heat source for the chemo-thermal process, the hydrogen will have a high enough temperature to heat the fluid in the turbo-compressor cycle. With an overall efficiency of 25% the system could produce 150 MWe of electricity. The electrical power cycle heat exchanger would use seawater as the cooling agent. The seawater will exit the electric power cycle heat exchanger in five forms. These would be desalinated steam, which will be sent through a condenser to yield desalinated water, warm brine, warm desalinated (reverse osmosis) water, salt, and extractable minerals (ionexchange) such as uranium, manganese, and gold. [0007]
Another product of the chemo-thermal process is very hot oxygen. The L & N Cycle proposes to use the hot oxygen to pass through a second heat exchanger to transfer heat to seawater to turn the seawater into steam to remove the salt. The steam would pass into a container to be mixed/sprayed with the oxygen exiting the heat exchanger for purification. The mixture would then proceed to a condenser to yield water. The L & N cycle uses heat normally wasted from the chemo-thermo process for cycles that can produce electrical power and desalinated water. [0008]

Claims

1. The L & N cycle files a claim as a system that applies a single heat source to state-of-the-art processes to produce a) hydrogen and oxygen from water through a chemo-thermal reaction, b) electricity with a modified regenerative brayton cycle, c) desalinate seawater through a thermal flash distillation desalination cycle and/or a reverse osmosis desalination cycle, and d) ion-exchange mineral extraction system.

2. The L & N Cycle files a claim as a system that applies a single heat source to state-of-the-art processes to produce a) hydrogen and oxygen from water through a chemo-thermal reaction and b) electricity with a modified Regenerative Brayton cycle.

3. The L & N Cycle files a claim as a system that applies a single heat source to state-of-the-art processes to produce a) hydrogen and oxygen from water through a chemo-thermal reaction, b) desalinate seawater through a thermal flash distillation desalination cycle and/or reverse osmosis desalination cycle, and c) ion-exchange mineral extraction system.