Industrial process flows are often too numerous to meter effectively using conventional technologies.

Silixa’s process metering technology enables flow distribution monitoring throughout an entire plant, mine, or oilfield environment simply by using a single length of fibre optic cable installed on process pipes.

This metering system measures the speed of turbulent eddies and acoustic energy. It can be used blindly, without costly calibration, on liquid, gas, slurry, and multiphase flows.

Applications

  • Mining
  • Water treatment
  • Process control

Benefits

  • Easy to retrofit, low opex
  • Low capex sensing instrumentation
  • No utility requirements at sensing zones
  • Enable increased process efficiency and reduced energy usage
  • Straightforward monitoring for trends in gas void fraction (GVF) and water in liquid ratio (WLR)

Silixa's process metering, flow distribution, monitoring gas void fraction trends

Silixa’s process metering enables flow distribution monitoring throughout an entire plant, mine, or oilfield environment simply by using a single length of fibre optic cable installed on process pipes.

Product specifications

Zones
10
Flow types Single phase, slurry, multiphase
Temperature range 0°C – 60°C
Blind accuracy <5%
Calibrated accuracy <2%
Integration CSV to cloud
Pipe material Steel, HDPE, PVC
Pipe size 2″ – 100″
 * customised variants available

Operating principles

  • Eddy currents are present in turbulent flow, moving close to the average velocity of the flow
    • phase independent
    • no calibration requirement
  • eddy currents distort the pipe wall
  • optical fibre attached to the exterior of the pipe measures these distortions, allowing direct observation of flow speed and sound speed
  • up to 10 individual stations per iDAS, with the same fibre

Case study: Multizone flow metering at Anglo American’s eMalahleni Water Reclamation Plant (EWRP)

Reference: Finfer, D., P. Newman, N. Rein, M. Amir. Pervasive metering of minewater flows and process water using distributed acoustic sensor technology, SAIMM “Water 2017”, Johannesburg, 10-11 July 2017.

Challenge

To demonstrate metering of water and slurry flows at several measurement zones along a single fibre within an operating minewater treatment plant.

Solution

Using a single optical fibre circuit, a multizone process metering system was installed on several processes on pipes ranging in size from 165 mm to 300mm. Metered flows include reverse osmosis manifold water, clarifier underflow slurry, and minewater slurry feed. Flow data was updated once per minute, and compiled data was transmitted automatically via email from South Africa to the London office every 24 hr. Data compilations were provided to the site over the duration of the 6 week pilot. Data allowed optimization of gas lift valve, increasing production.

Results

Flow rates were monitored successfully in each zone. Flow measurement output from the reverse osmosis process provided process insight along a manifold which would have been burdensome to instrument with conventional means. Over the course of a month period when both iDAS and reference sensors were functioning, the accumulated flow rates for the calibrated minewater and slurry flow rate zones were accurate to 1.5% and 0.5% respectively.

multizone flow metering, Silixa

Download the case study here.

Watch our distributed acoustic flow meter demonstration here.