Mission & Vision
Tulsa University Sand Management Projects (TUSMP) joint industry project (JIP) was established to address issues related to sand production and management such as solids detection and monitoring, erosion monitoring in offshore production, sand transport and deposition in multiphase flow.
Background & History
All offshore wells produce some sand. Many problems are associated with the produced sand such as particle erosion at high flow velocities and blockage of pipes when wells are shut in for some time. Many oil and gas companies are interested in the early detection of sand production from a well when several wells are connected to a single riser in offshore production conditions. Means of sand and erosion control are possible only when the quantity of the produced sand from each well is identified. Another potential problem related to sand production is the possible blockage of risers with sand when a well is shut in for a while. For a riser that is a few miles in length, the amount of sand that can settle during a shut-in can be significant and may be enough to block a section of the riser.
To address these problems, the investigators proposed to form a JIP to study sand detectors for their application in multiphase production piping systems by experimentation and theoretical analysis. A proposal was sent to many oil and gas and service companies in February of 1998 and a three-year project was proposed and was performed during 1998-2001. After discussion with many industry representatives, it was proposed to extend the JIP to gather additional data and address additional issues that are related to sand production management and control. Therefore in 2001, the principal investigators formed a JIP research consortium called Tulsa University Sand Management Projects (TUSMP) to extend the membership to other oil/gas companies that are interested in sand production management and control.
TUSMP Member Companies
Research Previously Performed
Sand Monitoring
The goals since the first research years have been: (1) testing commercially available sand and erosion monitors in a flow loop to see if there is a correlation between outputs from sand monitors and flow loop data and (2) developing models that help interpret output from sand monitors. A comprehensive experimental database to aid in the understanding of sand monitoring devices response to flow patterns, flow rates, sand rates, sand sizes and flow orientation has been obtained from recirculating and once-through flow multiphase loops with pipe diameters ranging from 1 to 4 inches. Three types of acoustic non-intrusive sand detectors were tested: Milltronics/Stresswave SandRanger (Sand Alert), ClampOn and Roxar. Intrusive Electrical Resistant (ER) probes were also used to monitor the sand in the flow by relating the metal loss resulting from the sand impingements on the probe. Output from each of the instruments has been gathered to demonstrate the monitor output response to a variety of measured sand concentrations, sand sizes and flow conditions. One of the primary objectives is to develop models that relate sand monitor output to sand rate capturing the effect of these parameters. From the models obtained, two user-friendly computer programs were developed: “Intrusive” and “Acoustic 2.0”. The first program calculates the total sand throughput corresponding to penetration loss from an intrusive monitor such as Cormon LTD ER Probes. Acoustic 2.0 predicts the correct trend in monitor output as a function of sand rate and can be used for calibrating acoustic sand monitors. The user is required to input calibration information on the flow conditions and on the monitor response for a given flow condition with and without sand. The output generated from the program is the sand production rate. This program uses a mechanistic model to predict the particle impact velocity that is then used to predict a representative particle impact kinetic energy Finally, an “Acoustic Sand Monitoring Guideline” was written to provide information regarding the behavior of non-invasive, passive acoustic sand monitors. Among the topics covered are theory, raw monitor response, and effect of particle concentration to monitor output, calibration, threshold particle rates, and the effect of many parameters on monitor output including flow orientation, flow regime, sand size, and pipe diameter.
Sand Sampling
Sampling is a key method to gather information on particles flowing in a system, for instance, particle properties, concentration, and distribution. Understanding particle concentration can aid better erosion estimation including magnitude and location. In this project, experiments were performed for a large range of conditions to better understand the effect on sampling. The work was focused on sampling in the vicinity of an elbow which is transitioning flow from horizontal to vertical. The parameters that were investigated are liquid and gas rates, pipe diameter, and elbow radius of curvature. The main delivery of this project was a “Sand Sampling Guideline” to suggest best practices to obtain a representative sample of the flowing fluids and solids with a heavy emphasis on the solids. To date, the following factors have affected sampling results: orientation, location of sampling point including fittings near sampling point, production gas rate, production liquid rate, and liquid viscosity.
Sand Transport Database
Sand transport in single and multiphase flows has been experimentally investigated by TUSMP. Particularly, the effect of different physical parameters on what is called “the critical velocity” was extensively investigated. Our definition in TUSMP for critical velocity is “velocity in which all particles are constantly moving along the pipe”. The experimental data was obtained using two pipe diameters (2 and 4-inch), several particle sizes and particle concentrations in both intermittent and stratified horizontal flow regimes. The effect of carrier liquid viscosity on particle transport was also investigated by using a viscous liquid. In this project, experiments were performed for a large range of conditions to better understand the effect on sampling. The work was focused on sampling in the vicinity of an elbow which is transitioning flow from horizontal to vertical. The parameters that were investigated are liquid and gas rates, pipe diameter, and elbow radius of curvature. The main delivery of this project was a “Sand Sampling Guideline” to suggest best practices to obtain a representative sample of the flowing fluids and solids with a heavy emphasis on the solids. To date, the following factors have affected sampling results: orientation, location of sampling point including fittings near sampling point, production gas rate, production liquid rate, and liquid viscosity.
Sand Transport Modeling
A generalized single-phase model that is applicable to liquid or gas flows was developed. The new model was validated with the TUSMP database and data that has been reported in the literature. The TUSMP model can predict critical velocity more accurately for various operating conditions both in liquid-solid and gas-solid flows than many models available in literature. By using an appropriate length scale, the new single-phase flow model was successfully extended to both intermittent and stratified multiphase flows. The new multiphase flow model takes into account the effect of different physical parameters which were previously investigated in the experimental part of the study. Unlike most of the previously proposed multiphase flow models, this model takes into account the effect of particle concentration on particle transport in multiphase flow. The new model was also validated with the TUSMP multiphase flow experimental database. This database includes data for both water-air and viscous liquid-air systems. A comparison of this model with previously proposed models in the literature shows that the TUSMP model is the only model that can predict the trend of experimental data correctly by changing different physical parameters. Finally, the mechanistic model is being developed into a design code with an MS Excel interface called “Sand Transport Critical Velocity Predictor” that can be used by the industry.In this project, experiments were performed for a large range of conditions to better understand the effect on sampling. The work was focused on sampling in the vicinity of an elbow which is transitioning flow from horizontal to vertical. The parameters that were investigated are liquid and gas rates, pipe diameter, and elbow radius of curvature. The main delivery of this project was a “Sand Sampling Guideline” to suggest best practices to obtain a representative sample of the flowing fluids and solids with a heavy emphasis on the solids. To date, the following factors have affected sampling results: orientation, location of sampling point including fittings near sampling point, production gas rate, production liquid rate, and liquid viscosity.