Improved Sand Management Strategy: Testing of Sand Monitors under Controlled Conditions

Abstract

Sand production has been a constraint to obtain maximized production rates for a number of years for several Statoil fields in the North Sea, due to issues related to: erosion potential not always easy to assess; safe operations: too many uncertainties related to increased sand production; and limited process handling capacity. Statoil has implemented the Acceptable Sand Rate (ASR), developed together with DNV, as a company strategy for increasing production rates by tolerating sand production within certain limits of maximum allowable sand volume, and maximum allowable erosion in the flow lines and the process system. Although these efforts have resulted in increased production, there is still a way to go to fully utilize the production potential. A key factor with respect to effective sand management is the collaboration and continuous communication among operators and suppliers, and the confidence and methodical approach that engineers and sand monitors' users should employ supported by a cross disciplinary effort. This paper will present the work carried out jointly by the operator and the suppliers through extensive lab work on the sand monitoring systems available today. The aim of the work is to explore the influence of piping geometry, sand characteristics and fluid/operational conditions on the sand monitors, in a controlled environment, in order to improve their implementation according to the ASR strategy. Instruments, test conditions, CFD analysis, results and conclusions will be described for both acoustic and erosion based monitoring devices.

Improving sand flow rate measurement of commercial ASDs and comparison with ultrasonic spectral analysis and filtering

“…As the probability of sand particles impacting the pipe wall increases at pipe bends and corners, it is recommended that the ASD be installed after any pipe bend [15 ]. Since the installation location geometry affects the reading of any individual ASD, it is important to calibrate the ASD after it is installed on the pipe [6 ].…”

“…There are various concerns about the accuracy of sand flow rate measurement using existing ASDs [6 ]. To address this issue, various experiments were performed with varying amounts of air velocity, sand flow rate and sand particle size.…”

“…Although ASDs have been used in various fields around the world, there are many concerns about the accuracy of sand flow rate measurement using these devices [6 ]. Clearly, there is room for improving the accuracy of sand flow rate measurement using them.…”

Sand rate model and data processing method for non-intrusive ultrasonic sand monitoring in flow pipeline

“…In addition, sand sensors and analog- (Emiliani et al, 2011). to-digital conversion circuit also generate electric noise signals. Hence, there always is non-zero output from the sensor.…”

“…Fig. 1 shows the working principle and location of non-intrusive sand sensors (Emiliani et al, 2011). They Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/petrol can provide real-time sanding information and allow building an early warning system for any increased sanding activities (Nabipour et al, 2012).…”