Organic Rankine Cycle Cogeneration with Segmented Heat Source Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for cogenerating electrical and thermal energy from low-temperature thermal discharges are inefficient, resulting in low power production and inadequate thermal energy valuation.
Innovation Solution
A cogeneration system incorporating an organic Rankine cycle module with a preheating exchanger and a heat source circuit featuring a second branch for thermal exchange at the preheating stage, allowing for optimized heat transfer and thermal energy valuation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If a Rankine cycle system is used to produce electrical energy from low-temperature thermal discharges, then electrical energy production is enabled, but the power produced is relatively low due to low thermodynamic efficiency
Solution Approach 1:
The heat source circulation circuit is segmented into two separate branches: a first branch arranged at the evaporator for high-temperature heat exchange, and a second branch arranged at the preheating exchanger for low-temperature heat exchange. This segmentation allows independent optimization of heat transfer in each branch, improving overall thermodynamic efficiency and power production from low-temperature thermal discharges.
Solution Approach 2:
The invention adds a new dimension to the heat source utilization by creating a dual-branch circulation system that operates at different temperature levels simultaneously. The first branch handles evaporator-level heat exchange while the second branch handles preheating-level heat exchange, effectively utilizing the temperature gradient across different stages of the Rankine cycle to improve overall energy conversion efficiency.
2Temperature
If thermal energy is recovered from the condenser outlet, then thermal energy recovery is achieved, but the temperature is quite low (around 40°C) and difficult to valorize
Solution Approach 1:
The second branch of the heat source circulation circuit performs preliminary heat exchange at the preheating exchanger before the main evaporator process. This preliminary action extracts thermal energy at an intermediate temperature level (between evaporator inlet and outlet temperatures), providing thermal energy at a more useful temperature range for various applications, rather than waiting until the low-temperature condenser outlet stage.
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 system achieves improved temperature matching between the work fluid and the hot source, optimizing energy conversion and enabling higher thermal energy valuation compared to traditional systems.
Implementation Method 1
a preheating exchanger, an evaporator... a second branch arranged at the preheating exchanger to ensure a heat exchange between the hot source from the evaporator and the working fluid at the preheating exchanger
Implementation Method 2
an evaporator... a first branch arranged at the evaporator to ensure a heat exchange between the hot source and the working fluid at the evaporator
Implementation Method 3
a first branch arranged at the evaporator to ensure a heat exchange between the hot source and the working fluid at the evaporator
Implementation Method 4
an expander or expansion device transforming the variation in enthalpy of the fluid into mechanical energy
Implementation Method 5
a cold exchanger allowing the condensation of the steam remaining after expansion, called a condenser
Implementation Method 6
a pump allowing the circulation of the fluid and the rise of its pressure
Data Source
Figure 1~2
AI summary
The present invention relates to a system for the co-production of electrical and thermal energy. The system comprises an organic Rankine cycle module for the production of electrical energy and a circulation circuit for a heat source (200) comprising a first branch (207) arranged at the evaporator (102) to ensure heat exchange (602) between the hot source (200) and the working fluid at the evaporator (102), characterized in that the circulation circuit for the heat source (200) comprises: a second branch (208) arranged at the preheating exchanger (101) to ensure heat exchange between the hot source (200) from the evaporator (102) and the working fluid at the preheating exchanger (101),The first branch (207) and the second branch (208) are arranged in series such that the heat source (200) circulates successively in the first branch (207) and then in the second branch (208), and a branch outlet (203) is arranged between the first branch (207) and the second branch (208) to provide an intermediate outlet of the hot source (200) from the evaporator (102) for the recovery of thermal energy from the hot source (200). It finds advantageous application in small-scale energy production systems using a Rankine thermodynamic cycle.