Background

Our client is a global mineral refiner, with headquarters in the USA and presence in Australia, South America, Canada, and Europe.

For one of our client’s process units, it was essential to have a clean barrier between the unit’s field instrument (transmitter) and process to enable safe, reliable, and accurate measurement. Any blockage or scale build up would be detrimental to the unit’s operation, and with no other option available our client would purge fluid into the unit – an imperfect attempt at a solution, with the purge inevitably becoming parasitic. Additionally, the growth of scale or crystallisation was merely delayed – not eliminated – with manual rodding out the eventual outcome.
Another issue was that during the period between the tapping point being totally open and completely blocked, the unit’s data would be unreliable. In our client’s case, measurement of the process by the transmitter was a combination of the actual process and purge back pressure as the aperture in the tapping point started to close. This would result in unreliable data over a period of days – or even months.

 

The manual task of rodding out a plugged tapping point presented two key challenges for our client:

1) Lost productivity:

Before any personnel could enter the environment where the tapping point was located, it was essential that the affected unit be either placed in bypass or totally isolated. Instrument Technicians could not rod into a live stream without risking their lives. The time from initial notification of a blocked tapping point through to assembling required personnel and tools, then executing the rodding out task, could take anywhere between 2- 12 hours – a considerable amount of lost production time.

2) Safety hazard:

Even with the instrument loop isolated, there was a significant safety risk to personnel who would typically use electric power drills to unblock tapping points. Exposure to caustic and other chemicals at high temperature also put people at risk of developing adverse health conditions.

In 2000 our client’s worst fear was realized. A fatality occurred at their USA refinery, directly attributed to the manual process of rodding out a tapping point. This incident coincided with an unrelated site visit from Clearguard CEO, Hans Sauer, who after learning of the fatality felt moved to develop an automated solution to this long-standing issue affecting industries across the world.

Solution

Hans committed to our client that he would source a solution to the manual rodding out process. With no existing product on the market, Hans applied his 30+ years in engineering and process control to design, engineer, and manufacture the Autorodder.
In 2004, Clearguard collaborated with our client to trial the first prototype of the Autorodder. Detailed discussions took place throughout the development process, with data sheets covering all aspects of the process. With several modifications along the way, in 2006 both Clearguard and our client felt satisfied that the Autorodder could be successfully implemented into filter flow applications at one of their plants. Training of site personnel was carried out by Clearguard, who also supervised the product’s installation.

 

Result

The Autorodder has completely replaced the manual rodding out practice for our client. Benefits to their operation include:

  • The associated safety risk to personnel has been eliminated.
  • Lost productivity from unit outages is no longer a concern.
  • Significant improvement in process measurement confidence. As the Autorodder keeps tapping points open 24/7, measurements are always accurate; the threat of blockages has been removed.
  • Significant reduction in purge consumption – benefitting the process with less dilution.