Furnace Control System Using Thermal Imaging for Temperature Profiles

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional furnaces face challenges in responding quickly to changes in operation, leading to suboptimal product quality, energy inefficiency, and potential refractory damage due to inadequate temperature control and measurement limitations.

Innovation Solution

A furnace control system utilizing a thermal imaging camera to generate real-time temperature profiles and a control unit that adjusts furnace conditions, including burner operation and fuel mixtures, to maintain optimal temperature distributions and minimize waste and energy usage, while accounting for reflection compensation and emissivity calculations to ensure accurate temperature measurements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If thermal imaging camera is used for real-time temperature monitoring, then response speed and measurement coverage are improved, but device complexity and cost increase

Engineering Contradiction:
Improveresponse speedVSAvoiddevice complexity
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The patent replaces mechanical/physical measurement devices (thermocouples, hand-held pyrometers, fibre temperature devices) with a thermal imaging camera system that uses optical/infrared detection to measure temperature fields. This substitution enables real-time, non-contact, multi-point temperature monitoring without the complexity of numerous discrete sensors or manual measurement operations.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The thermal imaging camera serves multiple functions: it monitors temperature distribution across the entire furnace, identifies hot and cold spots, tracks temperature changes over time, and provides data for process control optimization. A single device replaces multiple measurement points and methods, reducing overall system complexity while improving response speed.

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

2Measurement precision

If discrete temperature measurement devices are used, then device complexity is reduced, but measurement precision and information completeness deteriorate

Engineering Contradiction:
Improvemeasurement precisionVSAvoiddevice complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent transitions from single-point temperature measurements (0D or 1D) to two-dimensional temperature field mapping. The thermal imaging camera captures temperature distribution across the entire furnace cross-section and along its length, providing comprehensive spatial information that discrete sensors cannot obtain without complex arrays.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Area of stationary object

If emission measurements are performed in the exhaust stack, then measurement coverage is improved, but time lag increases due to large furnace volume and limited gas flow rates

Engineering Contradiction:
Improvemeasurement coverageVSAvoidtime lag
Core Design Contradiction:
Area of stationary objectVSLoss of time

Solution Approach 1:

The patent introduces thermal radiation as an intermediary carrier of temperature information. The thermal imaging camera detects infrared radiation emitted by the furnace interior surfaces and molten material, allowing direct observation of temperature conditions without waiting for gas to flow through the exhaust stack. This eliminates the time lag inherent in emission measurements while maintaining comprehensive coverage.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 solution enables continuous, real-time monitoring and adjustment of furnace conditions, enhancing product quality, reducing energy consumption, and prolonging furnace lifespan by maintaining precise temperature control and reducing NOx emissions.

Implementation Method 1

a thermal imaging camera configured to receive thermal radiation from a plurality of positions in a furnace and to generate an image which includes temperature information for the plurality of positions in the furnace

Methodology Applied
Scientific EffectThermal radiation: Thermal Radiation

Implementation Method 2

wherein the control unit comprises a reflection compensation module configured to identify and subtract a reflected component in the radiation received from a position in the furnace

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP3551588B1Control system for furnace
Publication Date: 2024.03.06 LAND INSTRUMENTS INTERNATIONAL LTD
  • EP3551588B1 patent drawingFigure 1
  • EP3551588B1 patent drawingFigure 2
  • EP3551588B1 patent drawingFigure 3

AI summary

There is provided a control system for a furnace. The control system comprises a thermal imaging camera and a control unit. The thermal imaging camera is configured to receive thermal radiation from a plurality of positions in a furnace and to generate an image which includes temperature information for the plurality of positions in the furnace. The control unit is configured to receive the image from the thermal imaging camera and to generate control signals for the furnace using the image.