What Is Paraffin and Asphaltenes?

Paraffin and asphaltenes are commonly occurring components of crude oils. These components have the potential to interfere with production and occasionally completely shut production down. Asphaltenes are large aromatic agglomerates composed primarily of heterocyclic rings. Held in solution in crude oil by naturally occurring petroleum resins that adhere to the outer surface of the asphaltene agglomerate, they will precipitate and deposit in your production system in locations where pressure drops allow the resins to desorb. Paraffins are saturated hydrocarbon waxes that will precipitate and deposit in areas where your production system’s temperature falls below the solubility temperature of the paraffins, known as the Wax Appearance Temperature (WAT). Both paraffin and asphaltenes can block a production system and halt production entirely. 

StrataChem’s paraffin and asphaltene dispersants and solvents products offer remedial treatment of the locations where paraffins or asphaltenes have already deposited in a system. These dispersants and solvents offer the capability to remove these deposits and restore a production system to its designed capacity. StrataChem’s solvents remove paraffin and asphaltene deposits when used in batch treatments by simply dissolving the deposits, while the dispersants contain oil-soluble surfactants that break up the paraffin or asphaltene deposit and disperse it in the oil.

StrataChem products can be used in continuous injection applications to control the deposition of waxes and asphaltenes, the normal procedure is to remove existing deposits through batch treatment. The volume of chemicals and frequency of treatment required for batch treatments will depend primarily on the severity of the problem. Once existing paraffin and asphaltene deposits are removed, continuous injection treatment provides a cost-effective approach to maintaining a system with no production-inhibiting deposits.

The production of gas and oil is often accompanied by water, either from the formation, from condensation, or from water injected as lift assist. Acid gases, such as hydrogen sulfide (H2S) and carbon dioxide (CO2) are often present in produced fluids, and oxygen is sometimes a contaminant in the water used for injection. These acid gases increase the corrosivity of the waters to steel, and can significantly impact the safe operating life of production tubulars and equipment, production vessels, and transportation systems.

The presence or absence of multiple phases (gas, water, and oil or condensate) in the same system can complicate the problem of controlling corrosion. The flow regime or pattern of fluids in a tubing string, vessel, or pipeline can have a significant impact on corrosivity. If a well or pipeline experiences “slug” or intermittent flow, highly corrosive conditions may exist in the area of the pipe in slug flow.

Pipelines can experience top-of-line corrosion when conditions promote the rapid condensation of water in a cooler section of the line, causing a film of water to form at the top of the line. This water at the top of the pipe becomes saturated with acid gases and corrodes the pipe. A further complication is a change in conditions, such as flow rate, temperature, and pressure over the life of a well, production or processing system, or pipeline, which can result in changing corrosivity or even a change in the potential corrosion mechanisms.

The control of corrosion in the oilfield can be a complex problem, requiring detailed analysis and a thorough understanding of the range of conditions expected during the life of the system prior to the development of a corrosion management plan. Our corrosion product line consists of a number of corrosion inhibitor formulations – some have been developed to address specific corrosion problems and others have been formulated to have wide applicability. Corrosion products are proven performers with a solid history of “raising the bar” in providing cost-effective corrosion protection in all oilfield operations. White’s corrosion inhibitors are effective in the severe environments found in cutting-edge production systems. Applications include controlling corrosion in all types of oilfield operations, including oil and gas production, processing, and transportation systems.

Our corrosion inhibitors are added to a system to help slow down or even stop a chemical reaction. Therefore, it is a substance, which, when added to a corrosive environment effectively decreases the corrosion rate of metals within it.

StrataChem’s corrosion inhibitors function using one of three main fundamental mechanisms:

1. Adsorption as a thin protective molecular film on the surface of the metal.

2. Formation of a bulky precipitate which coats the metal.

3. Changing the environment characteristics by the formation of bulky protective precipitates or removing aggressive constituents from the environment. One commonly used classification relates to whether the inhibitors are inorganic or organic.