Spherical Plastic Powder Production via Cryogas Envelope Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for producing pulverulent plastics with a spherical structure face issues such as product deposits on the supply unit and walls of the container, and challenges in achieving specific particle sizes, particularly with higher-viscosity plastics that tend to chemically decompose at temperatures required for processing.
Innovation Solution
A device and method involving a container with a nozzle device for spraying a hot melt, a cryogas supply unit with circumferentially distributed outlet openings for cooling the droplets, and a pneumatic discharge system, where the cryogas flow forms an envelope around the spray cone to prevent deposits and control particle size by adjusting droplet formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the supply unit is positioned within or near the spray cone to optimize cooling efficiency, then the cooling effect is improved, but product deposits accrue on the supply unit
Solution Approach 1:
The supply unit is segmented into multiple outlet openings arranged in a specific pattern, allowing the cryogas to be delivered from multiple directions to create a cooling envelope that avoids direct contact with the spray cone center where deposits would form
Solution Approach 2:
The supply unit is positioned in a different spatial dimension - above the spray cone rather than within it - creating a three-dimensional cooling envelope that surrounds the spray cone without the supply unit being in the direct path of the spray, thus preventing deposits while maintaining cooling efficiency
2Object-generated harmful factors
If the cryogas supply unit is positioned above the nozzle device to prevent deposits, then product deposits are avoided, but the cooling efficiency may be reduced
Solution Approach 1:
The cryogas acts as an intermediary medium, delivered through the supply unit above the spray cone, creating a cold gas envelope that indirectly cools the droplets as they fall through the envelope, preventing direct contact between the spray and supply unit while maintaining effective cooling
Solution Approach 2:
The cooling function is moved to a different spatial dimension by positioning the supply unit above the spray cone, creating a vertical cooling envelope that surrounds the spray path without requiring the supply unit to be in direct contact with the spray, thus maintaining both deposit-free operation and cooling efficiency
3Ease of manufacture
If higher temperatures are used to reduce viscosity for easier spraying, then the sprayability is improved, but chemical decomposition occurs
Solution Approach 1:
The plastic material is pre-heated to reduce viscosity before spraying, allowing it to be sprayed at lower temperatures that prevent decomposition. The pre-heating action prepares the material in advance so that the actual spraying occurs at safe temperatures
Solution Approach 2:
The temperature parameters are optimized to find the optimal range where the plastic has sufficiently low viscosity for spraying but remains below the decomposition temperature. The viscosity-temperature relationship is exploited to achieve sprayability at lower temperatures through extended heating time or mechanical agitation
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 solution effectively prevents product deposits and allows for specific control of particle size distribution, enhancing the yield and maintaining the spherical structure of the pulverulent plastics, particularly by ensuring the cryogas flow envelops the spray cone to prevent adherence to the container walls and optimizing droplet size for desired grain sizes.
Implementation Method 1
a cryogas flow, which comes into contact with the small droplets, exits into the interior space
Implementation Method 2
the melt exits the nozzle device and separates into small droplets that fall downward in the interior space
Data Source
AI summary
Device for producing pulverulent plastics with a spherical structure comprises: a container delimiting an interior space, a nozzle device disposed in an upper region of the interior space and connected to a supplying conveyor pipe for a hot melt of the product, wherein the melt exits the nozzle device and separates into small droplets that fall downward in the interior space, a supply unit for a cryogas in a predominantly liquid state having several outlet openings, wherein a cryogas flow, which comes into contact with the small droplets, exits into the interior space. The supply unit is located above or at the same level as the nozzle device, and method wherein, the hot melt of the product exits the nozzle device in the shape of a spray cone, the cryogas flow exits the supply unit in the shape of a cone, and the spray cone is located within the cone.