Safer, cleaner, more reliable chemical handling system
STT designs a Custom System Retrofit
Discover the Savings

Do you have an old facility that needs help? Or need some advice on a specific issue or project? We have a complete range of on-site services to help bring new life to your old system.

Fill out the form below and we'll be in touch within 24 hours.

"When it comes to service for reagent preparation systems, one name tops the list: STT Enviro Corp. More >>"

When it comes to service for reagent preparation systems, one name tops the list: STT Enviro Corp. STT was able to solve several issues with our system with one retrofit- engineered specifically to address our unique challenges. They made the entire process simple for our operators- from investigating the issues to engineering the retrofit to the final install –their professionalism and expertise made us comfortable and confident in the process. So comfortable in fact that we’ve hired them to retrofit a second system for us.


The Challenge

STT’s client has three steam assisted gravity drainage (SAGD) facilities in Alberta, each equipped with a Lime and Magnesium Oxide (MgO) chemical handling system. The oldest of the three systems, was supplied by STT Enviro Corp in 2007. The two newer systems, were supplied by a discount equipment supplier in 2011 and 2014.

In 2014, the client contacted STT in order to help return their oldest Lime and MgO system (originally supplied by STT) to its original condition. STT installed new rotary valves and upgraded the feeders to incorporate the most up to date technology and a decade’s worth of design improvements. Following the successful completion of this work, our client asked STT's Systems Specialists to review their two newer systems.

These two facilities were experiencing significant cost overruns due to ongoing maintenance issues specifically:


Plugging in the feed chutes between bin activator and the feeder.


Build up at discharge of the feeder


Build up in the slurry tanks.


Dust escaping from slurry tank to equipment room.

In addition there was concern that a failure in the flexible chute between the bin activator and feed equipment could engulf the silo skirt with dry Lime or MgO.

STT's Root Cause Findings

STT's Systems Specialists conducted a Mechanical Audit and System Review (MASR) on the first of the two systems and identified a number of issues with the original system design:

  1. Systems were originally supplied with dual outlet bin activators, vibration in the inactive leg was compacting chemical and plugging the chute.
  2. Because the bin activators used vibration to promote flow there needed to be a flexible chute at the discharge of the silo.
  3. The mixers impellers were undersized for the job, contributing to build up in the tank.
  4. The mix tanks were designed without baffles necessary to prevent vortex formation in the tanks further contributing buildup in the tank.
  5. The tank vent and scrubber was not designed for this service and had failed within weeks of operation allowing moisture to work its way into the feeder discharge and dust to escape from the tank.



The Solution: A Customized Retrofit Kit

STT took a systematic approach to understanding the design limitations of their system and developed a System Retrofit to solve the design, mechanical and safety issues and bring the system up to the design capacity.

The following improvements were made:

  • The silo bin activator was removed and replaced with an aeration bottom with two feed outlets. This eliminated the packing in the stand by feed outlet.
  • The flexible transition was removed from the system as there was no longer any vibrations being transmitted from the bin activator.
  • Baffles were installed in the slurry tank to facilitate proper mixing.
  • Two venturi style fans complete with a wet scrubber was installed to actively ventilate the tank to prevent moisture from getting into the feeder and reduce the dust escaping into the equipment room.
  • An aeration cone was installed to replace the bin activator, by doing so STT eliminated the issue of product compacting and restricting flow. The new design also eliminated the potential leak hazard associated with a flexible transition design.

Photo 1: STT System Specialist completes the install of the new feed trains for more controlled delivery of product to the mix tank.

Photo 2: A view of the installed retrofit including the new piping for the aeration bottom.

The Result

Our clients Lime and MgO systems are now safer, cleaner and more reliable than ever before. The success of the first Retrofit installation at has led the client to hiring STT to install the same retrofit on its newest system, bringing all three systems up to an industry leading standard.