Injection (Chemical/Gas/ Water)
Certain chemicals may need to be injected into oil or gas wells to counteract such conditions as scaling, hydrate formation, and corrosion. Traditionally, the injection dosages to individual wells have been controlled through valves located on the topside facilities. However, this requires a separate chemical feed line for each well – all the way from the chemical supply tank on the platform, through the control valve and the umbilical to the subsea well. In other words, the distribution of chemicals to each well is performed on the surface. For a subsea field development, the larger the number of trees and the longer the step-out from the host platform result in additional costs for each separate stainless steel tube bundled in the subsea umbilical.
Subsea chemical distribution is a better method that greatly reduces umbilical cost since only a single chemical feed line is required from the surface to the seabed. A subsea chemical distribution manifold branches the chemical feed to each well, and subsea chemical injection valves on each tree controls the dosage of the different chemicals to each well. Global Exergy is a pioneer in the area of subsea chemical distribution with the range of subsea chemical injection valves providing accurate, electrical control of the injection dosage. These valves also include built-in measurement of the injection flow rates, thus providing instantaneous feedback to topside operators that the desired injection dosage is actually being achieved at each tree. The most rigorous erosion testing proves the reliability of these valves in the most demanding applications, with injection flow rates up to 400 l/min.