Feeding a Low MIE Powder into a Mixing Vessel


A Case Study on Combustible Dust Risk Mitigation and Quick-Connect Transfer Solutions

__case-study-graphic-map 1
Cormetech - low MIE case study

Overview 

De Dietrich needed to transfer a product with low Minimum Ignition Energy (MIE) into a mixing vessel. The task required accurate material charging, proper grounding/bonding, and avoiding risks of combustible dust events. Since the head/lid of the mixer is hydraulically lifted after mixing is complete, our solution needed to quickly attach and detach from the mixing vessel. The following sections will provide a detailed analysis of this project.

About

The customer referenced in this case study is an industry leader in developing air pollution control solutions.

Challenges

  • Customer lacked experience with combustible dust materials.
  • This was a new process and product for the customer.
  • Product is ignition sensitive.
  • Accurate weighing and transfer into a new mixing vessel required.
  • System needed to be enclosed for dust containment and safety.
Cormetech - Junction box for controls and pneumatic components to dock Powder Pump with mixer
Cormetech - Vacuum pump, valves and instrumentation on mobile frame
Cormetech - Lower half of bulk bag unloading frame with rotary valve and charge hopper

Solution

After educating the customer about combustible dust hazards and what to be aware of, they conducted a dust hazard analysis (DHA). Upon completion of their DHA, they found that the solution we provided would be the safest means to transfer this new product into their process.

There were several key points to this solution. Below is a list of the major design features of the system:

  • A rotary valve was used in conjunction with load cells on the bulk bag unloading system to precisely dose the material into a charge hopper for transfer.
  • Grounding tabs and bonding straps were used throughout the system to ensure the equipment stayed grounded during use.
  • A hoist loaded unloading station was used due to difficult forklift access in the area.
  • To further increase safety during the transport of the material, instrumentation to allow nitrogen injection into the transfer line was used.
  • A mobile frame was designed to integrate the entire conveying system and vacuum pump into one structure, keeping everything compact and easy to move.
  • A pneumatic air cylinder and switches were used to index our Powder Pump system to the mixer inlet. To ensure safe operation of the cylinder, two hands are required for operation.
  • To avoid interference with the mixer, the Powder Pump was installed at a slight angle
  • A spray ball port with insertable spray ball was added to the connection hopper between the Powder Pump and mixer inlet to enable cleanout of the system before undocking

Conclusion

From initial contact and throughout the life of the project, De Dietrich maintained close communication with the customer. Ultimately, a system was designed and developed which met all of the customer’s needs and will allow them to continue progressing with the development of their new products.

For more information about this project, similar projects or if you want to talk specifically about your application, please feel free to reach out.

See how we can help to solve your industry
challenges