
Refinery Desalting
Desalting Optimization
The trend to processing lower quality crude oils, a more varied crude slate and the impact of environmental regulations all place increased demands on refinery operations. Nowhere is this more apparent than in the desalting operation.
In addition to maintaining excellent salt and sediment removal, an effective desalting program must also provide an oil free brine to ensure the integrity of downstream operations. Achieving these goals requires a broader approach than simply evaluating alternate chemistry at the desalter. It requires an evaluation of all operations that can affect desalter performance.
Cestoil Chemical has a range of proven technologies that have demonstrated effectiveness in addressing areas that impact desalter operations: tank farm operations, slop oil handling and waste water treatment.
Performing a root cause analysis can determine those factors contributing to poor desalter operation. Understanding the cause leads to the best solution, whether that involves a chemical program modification, operational change or equipment upgrade. Baker Petrolite's Crude Oil On-Line Library (COOL) contains information on crude oil and crude oil blends.
In addition to standard assay information, it includes Cestoil Chemical experience treating these crude oils. Information on desalting characteristics, corrosion and fouling issues, incompatibilities with other crude oils and special Baker Petrolite analyses performed in in-house laboratories are included.
Working in a team with refinery personnel, Cestoil Chemical can help customers make the best decisions about how to manage a wide range of crude oils and blends in a particular desalting operation.
Desalter Operations
The desalter is the refinery's main tool to remove many of the contaminants from the crude oil before further processing. Problems with the desalter operation can lead to increased corrosion, increased fouling, catalyst poisoning, product quality issues, and negative impacts on the wastewater treatment facility.
Emulsion breaking chemical programs from Baker Petrolite have been widely recognized as the industry leaders. Drawing on over 90 years of experience, Baker Petrolite has developed distinct desalter strategies which can be used to meet the individual refiner's goals. Continued research and development into emulsion breaking technology keeps Baker Petrolite at the forefront of technological advancements in this area, for example the unparalleled EXCALIBUR Contaminant Removal Technology.
Crude Tank Farm Operations
Several potential problems can occur in tank farm operations. Often the first crude offloaded from a tanker can come in with a higher emulsion and solids content than the remainder of the cargo, due to gravity settling during transit.
Similarly, tank switches can cause unit upsets, as high BS&W crude gravitates to the bottom of a storage tank. Slugs of solids and water can cause desalter problems. Baker Petrolite has found that pretreating the crude during the transfer to tankage can provide the extra time needed to reduce BS&W and "condition" filterable solids in the crude.
This treatment can help to minimize desalter upsets or allow the refinery to run lower quality “opportunity” crudes. The addition of special pretreatment emulsion breaking chemicals to selected crudes also enhances desalting by resolving any interface or rag layer remaining in the crude after water removal.
Wastewater Treatment
A refinery processing an increasingly varied crude slate may encounter problems with high oil content in the brine, despite the best efforts to manage desalter operations. Desalter effluent water quality can limit refinery crude oil selection flexibility or charge rates if the waste water plant can't handle the load. Baker Petrolite can address these situations in several ways. For example, the use of a solids wetting agent, in conjunction with a well managed mud washing program at the desalter, can reduce solids buildup in the desalter interface and reduce oil under-carry. Or, the use of polymers in the desalter wash water can provide an immediate improvement in brine quality and allow a quick recovery from a desalter upset. Baker Petrolite can also apply its wastewater plant chemical treatment and optimization expertise to improve the ability of the refinery to handle higher levels of oil and solids in the feed to the wastewater plant.