Automated CO2 Snow Block Dispensing for Consistent Sample Cooling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for preserving biological samples during clinical trials, such as using dry ice or cryogenic liquid nitrogen, are labor-intensive, costly, and prone to temperature gradients that can compromise sample quality, leading to increased logistical complexity and waste.

Innovation Solution

An automated system for generating and dispensing carbon dioxide (CO2) snow blocks within an automatic dispensing station, which allows for on-demand generation and precise control of CO2 snow block formation based on set points such as fill duration, weight, pressure, capacitance, temperature, or deformation, eliminating the need for on-site inventory and reducing handling and logistical challenges.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If manual loading of dry ice and samples into insulated boxes is used, then sample preservation is achieved, but labor intensity and operational complexity increase

Engineering Contradiction:
Improvesample preservationVSAvoidlabor intensity
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The system automatically generates CO2 snow blocks on-demand within the container using a CO2 reservoir and valve assembly, eliminating the need for manual dry ice loading. The controller autonomously regulates CO2 release to maintain target temperature without human intervention, making the system self-sufficient for sample preservation.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent replaces manual mechanical operations (loading dry ice, sealing containers, monitoring temperature) with an automated electronic control system that uses sensors, controllers, and electric valves to manage the cooling process, significantly reducing labor intensity while maintaining preservation reliability.

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

2Temperature

If conventional insulated boxes with dry ice are used, then sample cooling is achieved, but temperature gradients compromise sample quality

Engineering Contradiction:
Improvecooling effectVSAvoidtemperature uniformity
Core Design Contradiction:
TemperatureVSManufacturing precision

Solution Approach 1:

The system incorporates multiple CO2 release points (valves) positioned at different locations within the container to create localized cooling zones. The controller can independently regulate each valve to ensure uniform temperature distribution throughout the container, preventing hot spots and temperature gradients that would compromise sample quality.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

Temperature sensors continuously monitor the internal container environment and provide feedback to the controller. The controller adjusts CO2 release in real-time based on this feedback, maintaining target temperature uniformity and preventing temperature gradients from developing during the preservation process.

Inventive Principle:
Principle #23Feedback

3Duration of action of stationary object

If dry ice is loaded in advance for extended duration, then sample preservation is maintained, but cost and logistical complexity increase

Engineering Contradiction:
Improvepreservation durationVSAvoidlogistical complexity
Core Design Contradiction:
Duration of action of stationary objectVSDevice complexity

Solution Approach 1:

The system includes an integrated CO2 reservoir that automatically replenishes CO2 supply as needed during the preservation process. This self-service capability eliminates the need for advance dry ice loading and multiple refilling operations, reducing logistical complexity while extending preservation duration through automated resource management.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The CO2 reservoir is pre-filled with sufficient CO2 to cover the entire preservation duration, and the system is pre-programmed with the required preservation time. This preliminary preparation allows the system to autonomously manage CO2 consumption throughout the process without requiring intermediate human intervention or complex logistical arrangements.

Inventive Principle:
Principle #10Preliminary action

4Reliability

If liquid nitrogen-based vapor vessels are used, then sample preservation is achieved, but preparation time and cost significantly increase

Engineering Contradiction:
Improvesample preservationVSAvoidpreparation time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The system automatically generates CO2 snow blocks on-demand within the container using an integrated CO2 reservoir and valve assembly, eliminating the need for manual dry ice loading. The controller autonomously regulates CO2 release to maintain target temperature without human intervention, making the system self-sufficient for sample preservation.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system uses CO2 instead of liquid nitrogen, changing the refrigerant parameter to a more cost-effective and easier-to-handle substance. CO2 can be stored as a compressed gas at ambient temperature, eliminating the need for cryogenic handling, long absorption waiting periods, and decanting operations required by liquid nitrogen systems.

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 provides reliable and efficient preservation of biological samples by maintaining consistent temperatures, reducing handling and logistical complexities, and minimizing waste, while offering flexible and cost-effective sample transport solutions.

Implementation Method 1

introducing the liquid CO2 into the container through the fill conduit; the CO2 liquid undergoing a phase change to transform into CO2 snow block and offgas CO2 within the container

Methodology Applied
Scientific EffectPhase change: Phase Change

Data Source

PatentEP3728967B1Methods for automatic filling, charging and dispensing carbon dioxide snow block
Publication Date: 2023.07.26 PRAXAIR TECH INC
  • EP3728967B1 patent drawingFigure 1a~1b
  • EP3728967B1 patent drawingFigure 2a
  • EP3728967B1 patent drawingFigure 2b~4

AI summary

A method for automatically dispensing and vending carbon dioxide (C02) snow block is disclosed. The automatic dispensing system contains multiple containers of different volumes. A user can input the volume of C02 snow block into a controller, such as a programmable logic controller (PLC). The controller uses the inputted volume and process information to determine which container to utilize for the automated filling process. The controller can configure the selected container into a filling orientation into which liquid C02 can flow to generate C02 snow block. Upon detection of the completion of the fill, the container is configured into a dispensing orientation from which the C02 snow block is released into an access region from which the user can retrieve the C02 snow block. The control methodology may also be used to auto charge a single container located within a charging station as disclosed herein.