CHP Unit Waste Heat Recovery for Plastic Granule Drying

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Plastic processing is costly due to the high energy requirements for drying plastic granules, particularly the use of expensive electricity for material conditioning.

Innovation Solution

Utilizing waste heat and electricity from a combined heat and power plant to operate the plastic treatment and processing system, where waste heat is used to heat the drying medium and excess electrical energy powers the system's components, reducing operational costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If expensive electricity from the grid is used to heat the drying medium and operate the dehumidification units, then the plastic granules can be dried effectively, but the operational costs increase significantly

Engineering Contradiction:
Improvedrying effectivenessVSAvoidoperational cost
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The invention converts waste heat from the combined heat and power plant, which would otherwise be discarded, into a useful resource for heating the drying medium. This transforms a harmful waste product into a beneficial energy source, significantly reducing operational costs while maintaining drying effectiveness

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

Solution Approach 2:

The system uses its own internally generated waste heat and electricity to serve its drying and dehumidification needs, making the plant self-sufficient and reducing dependence on external expensive energy sources from the grid

Inventive Principle:
Principle #25Self-service

2Use of energy by moving object

If a combined heat and power plant is integrated into the system to provide waste heat and electricity, then energy costs are reduced, but the device complexity increases

Engineering Contradiction:
Improveenergy costVSAvoidsystem complexity
Core Design Contradiction:
Use of energy by moving objectVSDevice complexity

Solution Approach 1:

The invention merges the drying system with a combined heat and power plant, integrating energy production and waste heat utilization into a single unified system. This combination allows the plant to generate its own electricity and thermal energy, reducing external energy dependencies and overall costs despite the increased complexity

Inventive Principle:
Principle #5Merging (Combining)

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 significantly reduces energy costs for plastic processing by leveraging cheap waste heat and electricity, enhancing energy efficiency and making the process more cost-effective.

Implementation Method 1

The waste heat is used via the heat exchange process to heat the drying medium to the required drying temperature before it enters the drying tank

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 2

at least a portion of the waste heat is transferred directly or indirectly via at least one heat exchanger to a drying medium

Methodology Applied
Scientific EffectThermal energy transfer: Conduction (thermal)

Implementation Method 3

The cooling medium used to cool the CHP engine can also be used as waste heat. This cooling medium has temperatures in the range of approximately 80 to 95°C

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 4

The cooler is connected to the drying and regeneration unit to remove moisture from the return air

Methodology Applied
Scientific EffectCondensation: Condensation

Implementation Method 5

The drying and regeneration unit includes dehumidification units

Methodology Applied
Scientific EffectAdsorption: Adsorption

Data Source

PatentEP2883672B1Plant and method for the treatment and/or processing of polymeric materials
Publication Date: 2019.11.06 MOTAN HLDG
  • EP2883672B1 patent drawingFigure 1
  • EP2883672B1 patent drawingFigure 2
  • EP2883672B1 patent drawingFigure 3

AI summary

The system is equipped with at least one combined heat and power (CHP) unit (1), the waste heat (3 to 5) and/or generated electricity (6) of which are used at least partially to operate a device for plastics processing. For example, fuel (2) is supplied to an engine (15) of the CHP unit via at least one line (16), the engine being coupled to at least one generator (17) which supplies the electricity. The exhaust gases of the engine are fed via an exhaust gas heat exchanger (19) to heat a drying medium, which is used, for example, to dry plastic granules stored in a drying container (20). Since the waste heat and electricity generated by a CHP unit are significantly less expensive than electricity obtained from the grid, the device can be operated cost-effectively.