Polymeric Granule Drying With Adaptive Process Gas Flow

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing drying processes for polymeric granular materials, particularly those with high hygroscopic properties like PET, PA, and PC, face challenges in maintaining stable moisture and temperature conditions, leading to inefficient energy consumption and potential polymer degradation due to variations in material parameters and operational errors.

Innovation Solution

A process and system that dynamically adjust the process gas flow rate based on real-time measurements of inlet and discharging temperatures, as well as injection pressure, to stabilize the drying process and optimize energy use by anticipating and responding to material variations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If the polymeric granular material is dried inside a hopper with continuous hot dry air flow, then the moisture content is reduced to required levels, but the energy consumption becomes excessively high

Engineering Contradiction:
Improvemoisture contentVSAvoidenergy consumption
Core Design Contradiction:
Quantity of substanceVSUse of energy by moving object

Solution Approach 1:

The system performs preliminary measurement of the polymeric material temperature before drying, and based on this measurement, pre-adjusts the process gas flow rate to the optimal value. This preliminary action prevents energy waste by avoiding unnecessary high gas flow rates when the material is already at the desired temperature, while ensuring sufficient drying capacity when material temperature is low.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system continuously measures the temperature of the polymeric material during drying and uses this feedback information to dynamically adjust the process gas flow rate. The control unit compares the measured temperature with the desired temperature and modifies the gas flow rate accordingly, creating a closed-loop control system that optimizes energy consumption while maintaining effective drying.

Inventive Principle:
Principle #23Feedback

2Quantity of substance

If the drying process uses high gas flow rates to ensure thorough drying, then moisture removal is effective, but process stability is compromised due to material parameter variations

Engineering Contradiction:
Improvemoisture removal efficiencyVSAvoidprocess stability
Core Design Contradiction:
Quantity of substanceVSStability of the object's composition

Solution Approach 1:

The system measures the temperature of the incoming polymeric material before drying begins and pre-adjusts the process gas flow rate based on this initial condition. This preliminary adjustment ensures the drying process starts with optimal parameters, compensating for material variations before they can affect process stability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system dynamically adjusts the process gas flow rate during the drying operation based on real-time temperature measurements of the polymeric material. Rather than using a fixed high gas flow rate, the system continuously adapts the flow rate to match the actual drying needs, maintaining process stability while ensuring thorough moisture removal.

Inventive Principle:
Principle #15Dynamics

3Productivity

If the material temperature is increased closer to melting point for better drying, then drying efficiency improves, but polymer degradation occurs due to oxidation reactions

Engineering Contradiction:
Improvedrying efficiencyVSAvoidpolymer degradation
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The system continuously monitors the temperature of the polymeric material during drying and uses this feedback to adjust the process gas flow rate and prevent temperature from exceeding the safe threshold. When the material temperature approaches the critical level that could cause degradation, the system automatically reduces gas flow rate or adjusts heating to maintain temperature within the safe operating range.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system optimizes the process gas temperature and flow rate parameters to achieve effective drying without exceeding the maximum safe temperature of the polymeric material. By carefully controlling these parameters, the system maintains drying efficiency while preventing thermal degradation and oxidation of the polymer.

Inventive Principle:
Principle #35Parameter changes

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 ensures consistent drying conditions, reduces energy consumption, and prevents polymer degradation by maintaining optimal moisture and temperature levels, enhancing process stability and product quality.

Implementation Method 1

the water content in the granules is reduced to the minimum amount required by the transformation process

Methodology Applied
Scientific EffectEvaporation: Evaporation

Implementation Method 2

a continuous flow of hot dry air is introduced

Methodology Applied
Scientific EffectConvection: Convection

Implementation Method 3

the material is brought into the molten and semi-molten state by the friction forces with which the material is pushed by a screw advancing along the extrusion chamber

Methodology Applied
Scientific EffectFriction: Friction

Data Source

PatentEP3638968B1Process for drying polymeric granular material and system operating according to said process
Publication Date: 2025.09.03 PEGASO IND SPA
  • EP3638968B1 patent drawingFigure 1

AI summary

A process for drying polymeric granular material (2) comprises the steps of: - introducing into said drying hopper (10) a process gas having a predefined flow rate so as to heat and dry the polymeric granular material, - discharging a portion of the heated polymeric granular material into a transformation unit (100) for the polymeric material; - loading an amount of fresh polymeric granular material (2a) into the drying hopper. The process gas flow rate is regulated by measuring the inlet temperature of the fresh polymeric granular material (2a) and comparing it with a predefined inlet temperature of the fresh polymeric granular material, on the basis of which the predefined process gas flow rate has been calculated. If the measured inlet temperature is different from the predefined inlet temperature, the flow rate of the process gas is regulated on the basis of the measured inlet temperature.