Solids Level Measurement in Mining—A New Way

Douglas Morris Director of Marketing, Mining & Power Industries

Douglas Morris
Director of Marketing, Mining & Power Industries

Author: Douglas Morris

When it comes to mining there are a number of measurement applications that are unique to the industry. Accurately measuring the density of slurry and the level of an ore pile are two that come to mind. Although measuring level throughout the mining process is very common, getting an accurate solids level reading can be downright frustrating.

Radar, ultrasonic, and laser are single point measurements and the combination of irregularly shaped ore piles and dust most often cause these technologies to provide very inaccurate levels because they miss things like material buildups or cavities. Whether selling finished goods or running a concentration plant, getting a complete level picture is important in both instances and in order to do so, a three dimensional view is needed.

A new technology is available that addresses this need and uses sound to create a 3D surface image of the solids storage area. Examples of where this works are storage silos, bins, and stockpiles, regardless of the ore or mineral.

A caveat is that the sensor(s) has to be mounted to a fixed structure for reference/calibration purposes. The best way to see how this technology works is through a video. Continue Reading

How to Videos on Installing DP Flowmeters

3051SFA Annubar FlowmeterDifferential pressure (DP) is one of the most used and proven technologies for flow measurement. With averaging pitot tube (APT) technology, the impact pressure is sensed on the front of the device as the flow initially approaches the obstruction or bluff body which creates the pressure difference. For the most accurate measurement possible, it is essential to accurately measure the changing characteristics of the velocity flow profile. An integrated reading of the flow velocity profile samples across the full diameter of the pipe and produces a more accurate representation of the average velocity.

Rosemount Annubar flowmeters minimize this pressure drop to save energy and perform real-time mass and energy flow measurements with integral temperature design. The team managing the Rosemount measurement brand put together a series of “how to” videos on the installation process—tool requirements, device orientation guidelines, installation via Pak-Lok mounting, and Flo-Tap flowmeter installation.

In the first video, Tool Requirements and Receiving Guide (4:15 runtime), Emerson’s Mike Montgomery explains the tools required to install an Annubar Averaging Pitot Tube, as well as Inspection process recommendations upon receiving a new flowmeter. Continue Reading

Safety Instrumented System Solenoid-Operated Valve Approaches

Last week at the Emerson Exchange conference, I caught up with Emerson’s Riyaz Ali. You may recall Riyaz from many safety instrumented system-related posts. We discussed some of the trends in integrated positioners + solenoid valves + limit switches + valve position transmitters.

Riyaz Ali Senior Business Development Manager

Riyaz Ali
Senior Business Development Manager

Riyaz felt that this approach not in line with the safety instrumented system (SIS) general philosophy for several reasons.

For these devices with an integral solenoid-operated valve (SOV), the pneumatic path is only a single path and the requirement for a redundant path will not be met.

This will affect the PFDavg calculations as per ISA TR84.00.02-2002 part 2 using the simplified equation for a one-out-of-one (1oo1) arrangement:

λdu x T /2 (Note: λdu is dangerous undetected failure rate of equipment under control (EUC) and T is test interval.)

For solutions with external SOVs in series with smart positioners, this 1oo2 approach has a PFDavg:

λdu x T2 /3

A 1oo2 arrangement provides an improved PFDavg over a 1oo1 single box arrangement.

Riyaz notes that going to external SOV will improve safety reliability, which means either the SOV or smart positioner are capable of taking a valve to safe state. With integral SOVs with smart positioners, only one pneumatic path is available, which means there is no redundancy. Project teams may have to re-visit the HAZOP analysis to evaluate new safety integrity level (SIL) conditions. Continue Reading

Reliability and Its Bottom Line Impact

Reliability of your production process equipment impacts the bottom line by maintenance costs, related carrying costs, energy usage, and additional uptime related to equipment performance. Making improvements in reliability require people, processes, tools, and organizational support to move beyond current maintenance practices.

Bill Broussard Sales Leader, Reliability Solutions - Middle East & Africa

Bill Broussard
Sales Leader, Reliability Solutions – Middle East & Africa

Pipeline-Bringing-Greater-RIn a Pipeline magazine article, Bringing Greater Reliability (pp. 44-48), the editors interviewed Emerson’s Bill Broussard on the role of asset management in the oil & gas industry. When asked why asset management is so vital for oil and gas producers, Bill explained:

One KPI is a measure is spend on Equipment Replacement Value (ERV). Third Quartile Performers in the top and middle levels are spending 7.1 per cent – 8.9 per cent of ERV. First Quartile Performers are only spending 1.4 – 3.1 per cent. The differential is about 7.5 per cent, or US$7.5million for every $100million of equipment value.

Obviously moving into the top quartile has tremendous economic impact. Bill underscored the challenge of Continue Reading

Refinery and Chemical Plant Pressure Regulator Applications

Pressure regulators play an important role in process operations. Wikipedia describes their operation:

A pressure regulator’s primary function is to match the flow of gas through the regulator to the demand for gas placed upon the system. If the load flow decreases, then the regulator flow must decrease also. If the load flow increases, then the regulator flow must increase in order to keep the controlled pressure from decreasing due to a shortage of gas in the pressure system.

Michael Calaway Petrochemical Business Development Manager

Michael Calaway
Petrochemical Business Development Manager

I received an advanced copy of a whitepaper, Finding Industrial Pressure Regulators in Your Refinery or Chemical Plant, by Emerson’s Michael Calaway. Michael provides an overview of typical refinery and chemical plant pressure regulator applications and key advantages to the use of regulators.

Industrial regulators are most commonly found in plant utility systems, fired heaters, compressors, and storage tanks. The first area, plant utility systems, include nitrogen, steam, plant air, instrument air, and water systems. Due to their very nature plant utility systems require low cost, low complexity and highly reliable pressure control devices. These requirements make the industrial pressure regulator the primary choice.

For fired heaters including boilers and furnaces, the most common regulator applications are associated with the heater fuel gas system. Regulators are well suited for pressure control of the fuel gas header, burner, and pilot. Michael notes that the need for high turndown, quick speed of response, and reliability make industrial regulators an ideal choice for fired heater fuel gas pressure control. Regulator turndown in some cases can be considered almost infinite allowing for a single regulator to control at minimum fire and maximum fire conditions. Continue Reading