Optimized co-generating system and recovery method for power, water and nitrogen
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current energy and resource recovery systems for power generating plants with internal combustion processes fail to effectively utilize the heat energy and moisture present in flue gas, leading to energy wastage and inefficient resource recovery.
Innovation Solution
A special organic Rankine cycle (SORC) system, integrated with an internal combustion system, nitrogen generator, and gas-liquid separator, which utilizes a multi-stage heat exchanger configuration and turbo-expander to generate electricity from flue gas heat, while also recovering nitrogen and water through sequential vaporization, condensation, and separation processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If conventional heat recovery steam generators (HRSG) are used to recover heat from flue gas, then high-pressure high-temperature steam can be generated for utility use, but the system requires high temperature flue gas and cannot effectively utilize lower temperature heat energy
Solution Approach 1:
The patent applies parameter changes by transitioning from a conventional Rankine cycle designed for high-temperature steam generation to a special Organic Rankine Cycle (SORC) configured for low-temperature heat recovery. The SORC system uses organic working fluids with lower boiling points that enable effective heat extraction from flue gas at temperatures below what is required for traditional steam generation, thereby expanding the usable temperature range of flue gas heat energy.
Solution Approach 2:
The SORC system is designed to perform multiple functions: generating electricity from low-temperature flue gas heat, recovering heat energy across a broader temperature range, and potentially integrating with existing HRSG systems. This multi-functionality allows the system to utilize flue gas heat that would otherwise be wasted, improving overall energy recovery efficiency.
2Loss of energy
If flue gas is discharged directly into the environment without further processing, then the system operation is simple, but heat energy and moisture are wasted without recovery
Solution Approach 1:
The SORC system is designed to automatically recover heat energy from flue gas through its integrated heat exchangers and organic Rankine cycle process, converting waste heat into useful electrical power without requiring external energy input or complex control systems. The system serves itself by utilizing the inherent thermal energy in the flue gas stream to drive the cycle and generate power.
Solution Approach 2:
The patent converts the harmful waste heat and moisture in flue gas into beneficial resources. The SORC system captures what would otherwise be discarded thermal energy and transforms it into electrical power, while the moisture recovery system captures water vapor that would otherwise be released into the environment, turning waste streams into valuable resources.
3Loss of energy
If a single-stage heat exchanger system is used for heat recovery, then the device complexity is reduced, but the total heat recovery efficiency is limited
Solution Approach 1:
The heat recovery system is divided into multiple stages with separate heat exchangers optimized for different temperature ranges. This segmentation allows each heat exchanger to operate at its optimal temperature differential, maximizing heat transfer efficiency at each stage and enabling complete utilization of the flue gas heat spectrum from high to low temperatures.
Solution Approach 2:
The patent extends the heat recovery process into multiple thermal dimensions by using series and parallel heat exchanger configurations that operate at different temperature levels. This multi-dimensional approach allows simultaneous heat extraction at various temperature points along the flue gas path, significantly increasing total heat recovery compared to a single-stage system.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The SORC system enhances total heat recovery, prevents condensation within the exhaust duct, and increases electrical power generation by up to 18% while reducing CO2 emissions, with nitrogen collection rates up to 5.3 tons/hour and water collection rates up to 35 USGPM per MW of electrical power produced.
Implementation Method 1
The SORC system is configured to generate electricity with heat provided by a flue gas feed
Implementation Method 2
Vaporizing of the refrigerant comprises introducing the refrigerant through the first stage heat exchanger, the plurality of second stage heat exchangers, and the third stage heat exchanger sequentially
Implementation Method 3
introducing the vaporized refrigerant to the turbo-expander to generate electricity
Implementation Method 4
a turbo-expander, and at least one condenser. The SORC system is configured to generate electricity with heat provided by a flue gas feed
Implementation Method 5
condensing the vaporized refrigerant in the at least one condenser
Implementation Method 6
The nitrogen generator is configured to collect nitrogen from the flue gas feed, and is fluidly connected to the first stage heat exchanger and the plurality of the second stage heat exchanger
Implementation Method 7
The gas-liquid separator is configured to collect water from the flue gas feed
Implementation Method 8
The gas-liquid separator is configured to collect water from the flue gas feed, and is fluidly connected to the first stage heat exchanger
Data Source
AI summary
A recovery system includes a special organic Rankine cycle (SORC) system, an internal combustion system, a nitrogen generator and a gas-liquid separator. The SORC system includes a first stage heat exchanger (first HE), a plurality of second stage heat exchangers (second HE), a third stage heat exchanger (third HE), a turbo-expander, and at least one condenser. A recovery method, conducted in the recovery system, includes vaporizing a refrigerant, introducing the vaporized refrigerant to the turbo-expander to generate electricity, condensing the vaporized refrigerant in the at least one condenser, collecting nitrogen from the flue gas feed in the nitrogen generator, and collecting water from the flue gas feed in the gas-liquid separator. The refrigerant is vaporized by introducing the refrigerant through the first HE, second HE and third HE sequentially, and the flue gas feed through the third HE, second HE and first HE sequentially.