How do you handle chemicals with climate-sensitive flow properties? That’s the challenge for companies who produce resins and melamine using prilled urea. A hygroscopic chemical like urea prill becomes difficult to handle when it absorbs moisture.
For a multinational chemical company with a West Australian operation, the problem is compounded by volume and reliability requirements. The additional challenge for them is how to elevate material from an open storage pit exposed to extreme weather conditions to a storage silo.
Hygroscopic material processing challenge: Using prilled urea in chemical manufacturing operations
The company’s open storage pit receives around 88 tonnes (89,412 kg) of urea prill three times a week. The prilled urea then requires vertical conveying to elevate the material out of the pit and into a 180 tonne (182,888 kg) external storage silo. In addition to dealing with high-volume bulk material handling, the site has the following challenges:
- The shallow angle of the stainless steel pit liner made it nearly impossible to install a vertical conveyor.
- Equipment reliability is essential because maintenance is scheduled just once a year during an annual Christmas shutdown period.
The pit is located in an area exposed to humidity, rain and extreme heat. Conveying equipment needed to operate with minimal product retention since these climatic factors cause any urea residue to liquefy and then crystalise as a solid mass.
Vertical conveyor for quick and safe transfer of prilled urea
Why the AMC was selected
Floveyor’s aero-mechanical conveyor (AMC) with FloDisc® technology uses fully enclosed tubes to transfer materials. This makes the AMC an ideal solution to manage climate-sensitive hygroscopic material like urea prill. Floveyor has a long history working with chemical manufacturing companies, so a Floveyor AMC was a natural fit for this application.
Why the Endura product range was selected
The Floveyor Endura range is designed for effortless integration with complex applications and sites. Total batch transfer and easy cleaning are common features in all Floveyor AMCs, and the high throughput of the Endura F5 perfectly suited the application.
The throughput for this configuration is in excess of 80 tonnes (81,284 kg) per hour, more than double the chemical company’s requirement of transfers at a minimum of 30 tonnes (30,481 kg) per hour. This meant the prilled urea can be stored quickly and safely before it absorbs moisture.
At the end of the day’s transfer, any minimal residue of prilled urea in the infeed trough is blown clear by a small air nozzle. This efficient dry cleaning process leaves only a fine dusting of urea in the conveyor, that does not crystalise overnight.
Annual maintenance proved to be easy and involves removing the stainless steel grid and pit insert to inspect the inlet housing, sprocket, and single bearing. It’s an efficient process and purposely engineered to work effortlessly in a restricted space.
How a vertical conveyor adds value for chemical manufacturing operations
To overcome the shallow pit challenge, Floveyor was able to link two Floveyor Endura F5s to elevate the urea prill from the pit to the centre inlet of a storage silo. The machinery has a small footprint and a top-mounted drive, so it worked well in the shallow pit.
One additional advantage realised by the chemical company is that the two Floveyor vertical conveying mobile units are powered by an energy-efficient 5 kw motor. This provides additional operational benefit and reduces the overall total cost of ownership.
The result is a high-volume transfer of prilled urea into a silo storage year after year without incident. In addition, the Floveyor AMCs have maintained equipment reliability in a high-pressure resin manufacturing operation while requiring only minimal maintenance.
Using a vertical conveyor in your chemical manufacturing operation
If you would like more information about how a Floveyor vertical conveying system can contribute to the safe and efficient handling of hygroscopic material, get in touch with us. We are powder handling experts for the chemical industry and can help you find the right solution for your brownfield or greenfield operation.
