Peracetic Acid Filter Decontamination Without HEPA Wetting

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Solution Overview

Problem

Existing decontamination devices using peracetic acid can cause HEPA filters to become wet due to mist circulation, leading to increased pressure loss and potential filter failure.

Innovation Solution

A decontamination device that releases gaseous peracetic acid instead of mist, using a porous member impregnated with peracetic acid and a blower to ensure only gas reaches the filter, preventing mist release.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If peracetic acid disinfectant is atomized and circulated in the biosafety cabinet, then decontamination effectiveness is improved, but mist-like peracetic acid may wet the HEPA filter causing pressure loss

Engineering Contradiction:
Improvedecontamination effectivenessVSAvoidfilter wetting and pressure loss
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent changes the physical state parameter of peracetic acid from liquid mist to gas phase by controlling temperature and humidity conditions. The system maintains temperature above the boiling point of peracetic acid (35°C) and controls humidity to ensure complete evaporation, transforming the harmful mist into beneficial gas-phase disinfectant that effectively decontaminates without wetting the filter.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent utilizes phase transition of peracetic acid from liquid to gas state. By atomizing the liquid disinfectant and controlling environmental conditions (temperature and humidity), the system promotes complete evaporation to gas phase, preventing the formation of harmful mist while maintaining decontamination effectiveness through gas-phase circulation.

Inventive Principle:
Principle #36Phase transitions

2Productivity

If peracetic acid is heated to enhance gasification, then gasification efficiency is improved, but peracetic acid decomposition increases

Engineering Contradiction:
Improvegasification efficiencyVSAvoidperacetic acid decomposition
Core Design Contradiction:
ProductivityVSLoss of substance

Solution Approach 1:

The patent optimizes temperature parameters to a specific range (above boiling point of peracetic acid but not excessively high) to achieve efficient gasification while minimizing decomposition. The system controls temperature to be sufficient for evaporation ( >35°C) but below temperatures that cause rapid decomposition, balancing gasification efficiency with substance stability.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The system incorporates humidity sensing and control mechanisms that provide feedback to adjust heating power. When humidity is detected to be sufficient for complete evaporation, the system reduces heating intensity to prevent overheating and decomposition, while maintaining adequate gasification for effective decontamination.

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

Reduces the likelihood of HEPA filters becoming wet, minimizing dust solidification and pressure loss, thereby maintaining filter efficiency.

Implementation Method 1

a porous member impregnated with a chemical solution containing peracetic acid... gas containing peracetic acid is released

Methodology Applied
Scientific EffectEvaporation: Evaporation

Implementation Method 2

a blower disposed on the flow channel... gas containing peracetic acid is released toward the air filter

Methodology Applied
Scientific EffectForced Convection: Forced Convection

Implementation Method 3

gas containing peracetic acid is released such that the gas reaches the air filter

Methodology Applied
Scientific EffectDiffusion: Diffusion

Data Source

PatentEP3950020B1Decontamination devices and system
Publication Date: 2026.04.22 NITTA CORP
  • EP3950020B1 patent drawingFigure 1
  • EP3950020B1 patent drawingFigure 2
  • EP3950020B1 patent drawingFigure 3

AI summary

A decontamination device according to an aspect of the present invention is configured to decontaminate an air filter for particle removal. This decontamination device is configured to release gas containing peracetic acid such that the gas reaches the air filter and not release mist containing peracetic acid. A system according to another aspect of the present invention includes a container and a decontamination device. The container is configured to hold an air filter for particle removal. The decontamination device is configured to release gas containing peracetic acid into the container such that the gas reaches the air filter and not release mist containing peracetic acid.