Thermal Power Plant Preheating via Compressor Waste Heat Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thermal power plant and compressor systems face inefficiencies due to energy losses during the compression process, particularly in multi-stage compressors driven by turbomachines like steam turbines, where minimizing these losses is crucial for improving overall efficiency.
Innovation Solution
The system integrates a thermodynamic connection between the cooling systems of the compressor and the preheaters of the thermal power plant, allowing waste heat from the compressor to be directly utilized as useful heat, reducing the energy required for the thermal power plant's operation, and includes a multi-stage compressor design with geared impellers and a central gearbox for efficient power transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If waste heat from compressor cooling systems is discharged without utilization, then the system operates with simple configuration, but energy is lost and overall efficiency decreases
Solution Approach 1:
The patent merges the compressor cooling system with the thermal power plant's preheater system by connecting the cooling water outlet to the preheater inlet and the preheater outlet to the cooling water inlet. This integration allows waste heat from the compressor to be directly utilized for preheating feedwater, eliminating energy loss while maintaining a relatively compact system configuration.
Solution Approach 2:
The patent converts the harmful waste heat that would normally be discharged into a beneficial resource by using it to preheat the feedwater in the thermal power plant. The cooling water from the compressor, which contains thermal energy, is redirected through the preheater to heat the feedwater before it enters the boiler, thereby converting an energy loss into an energy gain.
2Productivity
If additional preheating equipment is added to utilize waste heat, then energy efficiency improves, but device complexity and initial investment increase
Solution Approach 1:
The patent makes the existing preheater serve dual functions: its original function of preheating feedwater using steam extraction, and an additional function of recovering waste heat from the compressor cooling water. This multi-functionality allows the system to improve energy efficiency without adding separate preheating equipment, thereby avoiding increased device complexity and initial investment.
3Loss of energy
If the thermal power plant operates independently without heat integration, then the system is simpler to control, but overall energy utilization is lower
Solution Approach 1:
The patent establishes a continuous heat exchange pathway where cooling water from the compressor continuously flows through the preheater to transfer heat to the feedwater, and then returns to the compressor. This continuous thermal coupling ensures sustained energy recovery and utilization, improving overall energy efficiency while the control system manages the integrated operations through coordinated temperature and flow rate adjustments.
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
This configuration enhances the thermal power plant's efficiency by utilizing waste heat as useful energy, reducing the energy needed for operation and increasing technical output, while maintaining safe and energy-saving conditions across all operating conditions.
Implementation Method 1
at least one cooling system downstream of a compression stage or between compression stages, by means of which at least one heat flow is extracted from the second process fluid
Implementation Method 2
the waste heat from the compression process is supplied to the thermal power plant as usable heat
Data Source
Figure 1
Figure 2
AI summary
The invention relates to a plant (A) having a thermal power plant (WKA) and a multi-stage process compressor (MSC), wherein the thermal power plant (WKA) comprises: – pump (PMP), – boiler (BOI), – turbine (TRB) having one output shaft (SD1) or double output – condenser (CND), wherein a first process fluid (PF1) circulates in the thermal power plant (WKA), wherein the process compressor (MSC) has at least one stage (ST1,…, STn) in which a second process fluid (PF2) is compressed, and at least one cooler (IC1,…, ICn) downstream of a process stage (ST1,…, STn), by means of which at least one first waste heat flow (QF1,…, QFn) is withdrawn from the second process fluid, wherein an output shaft (SD1) of the process compressor (MSC) is mechanically coupled to the drive shaft (SD2) so that the turbine (TRB) drives the process compressor (MSC). It is proposed that the thermal power plant (WKA) has, in the flow of the first process fluid (PF1) between the pump (PMP) and the boiler (BOI), at least one preheater (PH1,…, PHn) by means of which a pre-heat flow (PRF) is supplied to the first process flow (PF1), wherein at least one cooler (IC1,…, ICn) is connected, by means of at least one exchange line (FCC), to the thermal power plant (WKA) such that at least one part of the waste heat flow (QF1) is supplied as a preheat flow (PRF) to the first process fluid (PF1) between the pump (PMP) and the boiler (BOI).