Granular Polymer Drying Plant With Process Gas Purification

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing drying plants for granular polymer materials, particularly those containing recycled polyethylene terephthalate (rPET), suffer from high chemical impurities like benzene, acetaldehyde, and residual oils, which compromise product quality and emit pollutants, while being inefficient and complex.

Innovation Solution

A drying plant with a process gas circuit that includes a dehumidification and heating unit, a purification group with a condenser and activated carbon filter, and a cyclone separator to remove contaminants, optimizing energy efficiency and reducing emissions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If a conventional drying plant uses a closed process gas circuit with recirculation, then energy efficiency is improved, but chemical impurities (benzene, acetaldehyde, residual oils) accumulate in the process gas and compromise product quality

Engineering Contradiction:
Improveenergy efficiencyVSAvoidchemical impurities
Core Design Contradiction:
Use of energy by moving objectVSObject-generated harmful factors

Solution Approach 1:

The invention extracts harmful chemical impurities (benzene, acetaldehyde, residual oils) from the recirculating process gas using a purification system comprising a condenser and activated carbon filter, while maintaining the energy-efficient closed circuit configuration

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The purification system acts as an intermediary between the drying chamber and the dehumidification unit, removing chemical impurities from the process gas before it enters the dehumidification stage, thereby preventing contamination accumulation

Inventive Principle:
Principle #24Intermediary (Mediator)

2Loss of energy

If the process gas is continuously circulated without purification, then energy consumption is reduced, but the quality of the dried polymer material deteriorates due to contaminant accumulation

Engineering Contradiction:
Improveenergy consumptionVSAvoidquality of dried polymer material
Core Design Contradiction:
Loss of energyVSManufacturing precision

Solution Approach 1:

The purification system extracts chemical contaminants from the recirculating process gas, enabling continuous circulation without quality degradation

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The system discards harmful chemical impurities through the purification system while recovering and recirculating the cleaned process gas, maintaining both energy efficiency and product quality

Inventive Principle:
Principle #34Discarding and recovering

3Manufacturing precision

If a purification system is added to remove chemical impurities, then product quality is improved, but device complexity increases

Engineering Contradiction:
Improveproduct qualityVSAvoiddevice complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The invention merges the purification function into the existing process gas circuit by positioning the purification system between the drying chamber and the dehumidification unit, utilizing the same gas flow path without requiring separate purification circuits

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The process gas circuit serves multiple functions: drying the polymer material, dehumidifying the process gas, and purifying it from chemical impurities, thereby reducing the need for separate dedicated systems

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

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 plant effectively reduces chemical impurities in rPET, enhancing product quality and minimizing pollutant emissions, with improved energy performance and simplified construction.

Implementation Method 1

a condenser (32) which is configured to cool the process gas to a predefined condensation temperature of the contaminating substances so as to separate from the process gas the contaminating substances condensed in this manner

Methodology Applied
Scientific EffectCondensation: Condensation

Implementation Method 2

a filter (33) which is positioned at the outlet from the condenser (32) and which contains activated carbon capable of absorbing any non-condensed contaminating substances

Methodology Applied
Scientific EffectAdsorption: Adsorption

Implementation Method 3

a dehumidification and heating unit (20) which is configured to dehumidify and heat the process gas to predefined humidity and temperature values for supply to the hopper (2), respectively

Methodology Applied
Scientific EffectHeating: Heating

Data Source

PatentEP4235070B1Plant for drying granular polymer material
Publication Date: 2025.10.01 PEGASO IND SPA
  • EP4235070B1 patent drawingFigure 1
  • EP4235070B1 patent drawingFigure 2

AI summary

A plant for drying granular polymer material comprises a hopper, in which granular polymer material is dried, and a process gas circuit which is configured to supply a process gas to the hopper in order to dry the granular polymer material.