Solid Oxide Fuel Cell Heat Recovery for Gas Burner Process Heat

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Industrial processes face significant energy losses due to inefficient use of heat generated by gas burners, and existing methods to reduce these losses are costly and only partially effective.

Innovation Solution

A system that utilizes process heat generated by a gas burner to heat a high-temperature fuel cell system, which in turn uses waste heat to generate electrical energy, optimizing energy usage and reducing losses by thermally coupling the burner, process unit, and fuel cell system through heat exchangers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If gas burners are used to generate process heat, then heat can be provided for industrial processes, but significant energy losses occur to the outside

Engineering Contradiction:
Improveprocess heat temperatureVSAvoidenergy losses to outside
Core Design Contradiction:
TemperatureVSLoss of energy

Solution Approach 1:

The patent converts the harmful waste heat from the burner into a beneficial resource by feeding it to the fuel cell system. The waste heat that would otherwise be lost to the outside is now utilized to heat the fuel cell to its operating temperature and to preheat the operating air, thereby generating electrical energy while reducing overall energy losses.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent merges the burner system with the fuel cell system by thermally coupling them through heat exchangers. The burner and fuel cell are integrated into a single combined system where waste heat from the burner is transferred to the fuel cell, allowing simultaneous heat generation and electrical energy production from the same fuel source.

Inventive Principle:
Principle #5Merging (Combining)

2Loss of energy

If exhaust gas heat exchangers are used to preheat combustion air, then energy losses are reduced, but the system becomes cost-intensive and only partially effective

Engineering Contradiction:
Improveenergy lossesVSAvoidsystem complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The fuel cell system serves multiple functions: it generates electrical energy, preheats its own operating air using waste heat, and can potentially provide process heat. This multi-functionality eliminates the need for separate preheating systems and reduces overall system complexity while maximizing energy utilization.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The fuel cell system is self-sufficient by using its own waste heat to preheat the operating air required for its operation. This self-service capability eliminates the need for external preheating systems and reduces dependency on additional energy input or complex external heat exchange systems.

Inventive Principle:
Principle #25Self-service

3Use of energy by moving object

If high-temperature fuel cell systems are heated by waste heat, then electrical energy can be generated with higher efficiency, but the system requires precise thermal adjustment to optimal operating temperature

Engineering Contradiction:
Improveenergy conversion efficiencyVSAvoidthermal adjustment complexity
Core Design Contradiction:
Use of energy by moving objectVSEase of manufacture

Solution Approach 1:

The system incorporates thermal feedback control where the temperature of the fuel cell is continuously monitored and the heat input from the burner is adjusted accordingly. The waste heat from the burner automatically feeds back to maintain the fuel cell at its optimal operating temperature, creating a self-regulating system that simplifies thermal management.

Inventive Principle:
Principle #23Feedback

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 approach enhances the overall efficiency of the system, making fuel cell systems more efficient than heat engines, reduces the number of components, and allows for robust and cost-effective design, while utilizing heat losses across a wide temperature range to generate electrical energy.

Implementation Method 1

at least one heat exchanger for transporting the first portion of the heat generated by the burner to the process unit

Methodology Applied
Scientific EffectHeat exchanger: Heat Exchanger

Implementation Method 2

The at least one heat exchanger heats the gases supplied to the fuel cells, in particular natural gas and air, with exhaust air from the burner and/or the process unit

Methodology Applied
Scientific EffectThermal energy transfer: Conduction (thermal)

Implementation Method 3

Fuel cell systems are used to directly convert chemically bound energy into electrical energy

Methodology Applied
Scientific EffectFuel cell: Fuel Cell

Implementation Method 4

the electrochemical conversion of the gas

Methodology Applied
Scientific EffectElectrochemical conversion:

Data Source

PatentEP3859847B1Use of solid oxide fuel cells in process heat generation
Publication Date: 2024.01.10 ROBERT BOSCH GMBH
  • EP3859847B1 patent drawingFigure 1
  • EP3859847B1 patent drawingFigure 2
  • EP3859847B1 patent drawingFigure 3

AI summary

A system for utilizing process heat for at least one thermal process is disclosed, comprising a burner, in particular a gas burner, for generating heat, comprising at least one process unit for utilizing a first part of the heat generated by the burner, and comprising at least one heat exchanger for transporting the first part of the heat generated by the burner to the process unit, wherein the system includes at least one high-temperature fuel cell system which can be heated to an operating temperature by a second part of the heat generated by the burner. Furthermore, a method for utilizing heat from a burner is disclosed.