Turbulence and shear in conventional choke and control valves do mix and emulsify petroleum fluids. A typical consequence is reduced separation efficiency of downstream gravity separators, resulting in retarded oil-water separation. A new cyclone-based low shear valve is developed, enhancing oil-water separation and reducing environmental impacts from petroleum activities. Five years of experimental and theoretical studies are reviewed, including recent tests involving six different North Sea crude oils. For a majority of oils the cyclonic valve has a significant positive effect on oil-water separation. Moreover, it is documented that the cyclonic valve has an overall positive effect on both oil-in-water and water-in-oil concentrations, across a large range of water cuts. The cyclonic valve has a consistent positive effect on oil droplet size for all crude oils in produced water. Typically, oil droplet effluent from a cyclonic valve has twice the size of droplets exiting a standard valve. The effect is largest for the smallest volumetric fraction of droplets. This new valve technology is realizing great potential in petroleum processing; i.e., less droplet break-up and less fluid emulsification. This paper demonstrates quality improvements for both crude oil and produced water. Replacing choke valves might be the ultimate application for cyclonic valves. However, experimental results demonstrate that control valves upstream any gravity-based separator are potential targeted applications for cyclonic valves. Introduction Valves in Petroleum Production Valves are widely distributed in petroleum production and hydrocarbon processing facilities (Figure 1). In their operation throttling valves possess an effective restriction to flow. Choke valves and control valves are typical throttling valves used to regulate flowrates and pressures of fluids in a petroleum process.

Turbulence and shear in conventional choke and control valves do mix and emulsify petroleum fluids. A typical consequence is reduced separation efficiency of downstream gravity separators, resulting in retarded oil-water separation. A new cyclonebased low shear valve is developed, enhancing oil-water separation and reducing environmental impacts from petroleum activities. Five years of experimental and theoretical studies are reviewed, including recent tests involving six different North Sea crude oils. For a majority of oils the cyclonic valve has a significant positive effect on oil-water separation. Moreover, it is documented that the cyclonic valve has an overall positive effect on both oil-in-water and water-in-oil concentrations, across a large range of water cuts. The cyclonic valve has a consistent positive effect on oil droplet size for all crude oils in produced water. Typically, oil droplet effluent from a cyclonic valve has twice the size of droplets exiting a standard valve. The effect is largest for the smallest volumetric fraction of droplets. This new valve technology is realizing great potential in petroleum processing; i.e., less droplet break-up and less fluid emulsification. This paper demonstrates quality improvements for both crude oil and produced water. Replacing choke valves might be the ultimate application for cyclonic valves. However, experimental results demonstrate that control valves upstream any gravity-based separator are potential targeted applications for cyclonic valves.Hydrocyclones

Summary In hydrocarbon production and processing, choke and control valves mix and emulsify petroleum phases. The consequence is often that the efficiency of separation processes is affected and finally that the quality of oil and water phases is degraded. Over the last few years, low-shear valves targeting petroleum processes have emerged on the market. This paper presents four separate live-fluid experiences from low-shear valve installations, each surveyed and documented by an independent third party. Three of the installations refer to choke valves, whereas the fourth installation refers to a control valve. For each installation, standard choke and control valves were used as reference valves. In terms of downstream separation efficiency, the low-shear choke valves reduced oil-in-water concentrations respectively by 70, 45, and 60%, by total average. In the control valve application, the low-shear valve, which was located between the hydrocyclones and a compact flotation unit, reduced the oil-in-water concentration by 23%. In sum, the field installations have demonstrated that low-shear valves significantly and consistently reduce oil-in-water concentrations and thus improve the produced water quality. The results signify that low-shear valves may be used in debottlenecking separation and produced water treatment processes, reducing the environmental influence from produced water discharges. Because the low-shear technology enables processing of petroleum phases with less effort, energy, and chemicals, it also reduces emissions to air.