Resolving Chemical Reaction challenges in the Oil Field
The oil exploration and production process involves a series of chemical and physical processes that occur continuously and their effective management can mean the difference between success and failure.
Antifoamers
Foaming occurs in crude oil formations due to various factors such as pressure changes, occurrence of contaminants and presence of bore mud, sand deposits and wax. Foam in the crude oil can lead to poor well production, cavitation problems in pump, poor separation, loss in pumping efficiency, and irregular fluid flow. Antifoamers combine with the nucleation sites of the contaminants and reduce foam generation.
Asphaltene control
Asphaltenes occur as stable colloidal substances in the crude oil. They have high polarity and their precipitation occurs in various aspects of production and transportation. They are caused by; drops in pressure, fluctuating PH, unstable flow or shear flow and presence of carbon dioxide. Asphaltenes cause formation of heavy emulsions in the crude tanks, which eventually reduces recovery of oil and blockage of pipelines. They are managed by use of asphaltene control substances, which dissolve the asphaltene colloids as well as inhibit asphaltene precipitation.
Biocides
Microbial contamination is bound to occur in various stages of the oil production process and their presence can cause interference in oil production process. Some bacteria in oil production include;
- Slime producing sessile bacteria,
- Sulphate altering bacteria; causes contamination of the oil well leading blocked oil production ,and reduce water penetration in clearance wells.
It is important for oil producers to prevent establishment of bacterial colonies and they are impossible to clear. Biocides are important for checking the growth of these tough bacteria and ensure no biofilms are formed.
Corrosion Inhibitors
Corrosion is one of the biggest problems in oil production and must be managed with appropriate caution. It leads to deterioration of piping systems, storage tanks, and faster equipment degradation. Corrosion inhibitors are critical in oil production to maintain equipment integrity as much as possible.
Drag Reducers
Development of high frictional pressure in the pipes of crude oil leads to poor pumping efficiency and possible pump failure. Drag reducers lessen the turbulence in the pipe thus enhancing the flow rate and increasing the pumping efficiency.
Emulsion Breakers
When oil and water are forced to mix, emulsions develop, which interfere with the crude pumping process. Emulsion breakers target the boundary /interface between the oil and water and create a strong film that prevents coalescing of the droplets to form larger droplets and break the emulsion.
Hydrogen Sulphide Scavengers
Bacterial action of sulphate reduction causes occurrence of hydrogen sulphide gas. This gas causes severe corrosion of gas and crude pipes causing leakages and failure in production. This process can be prevented by creation of an inhibiting layer using the hydrogen-sulphide scavengers.
Hydration Inhibitors
Hydrates are chemical formations in the piping lines that can grow as the reactions continue. They lead to formation of hydrate plugs in the pipes leading to serious blockages. Hydrate inhibitors are therefore used to chemically react with the hydrates and cause them dissolve in solution.
Conclusion
The oil production process requires intensive management of chemical reactions, which are many, and varied. If these reactions are left unchecked, serious damages and downtimes are experienced and can lead to drastic reduction in production. The most serious reactions include corrosion, hydrate occurrence, emulsion formations and friction reduction.
This article has been written by Govind Patel.
