Difference between SULFEX® (sulphonated asphalt) and GILSONITE
SULFEX® Additive (sulphonated asphalt): – this is neither bitumen, nor gilsonite, but sulfonated bitumen, a completely different product. In the production of SULFEX® additives , specially selected bitumen is used as raw material.
Gilsonite: a kind of natural bitumen. Gilsonite resin is a complex combination of hydrocarbons, obtained as raffinate in an extract from liquid extraction of gilsonite. It consists predominantly of a complex combination of olefins, naphthalenes, pyrroles, pyridines and other hydrocarbons with a softening point of 80 ° C to 175 ° C.
Bitumen: bitumen is a bituminous substance derived from petroleum during the distillation of lighter hydrocarbons and partial oxidation of the sediment. Bitumen comes in the form of a residue in the distillation of crude oil in refineries, and the composition of bitumen depends on the type of crude oil used and the process of its distillation.
As a rule, bitumen is a mixture, which includes:
- Saturated compounds
- Aromatic compounds
- Resins
- Asphaltene
It should be noted that all available double bonds from hydrocarbons are excluded during the sulfonation process in the production of additives SULFEX® additive. A surplus amount of sulfonating agent is used to guarantee complete sulfonation and an uninterrupted processing process at the plant. This process is constantly monitored by testing the solubility of the SULFEX® additive in water.
COMPARISON OF SULFEX® (sulphonated asphalt) AND GILSONITE ADDITIVES
Currently, there are no equivalent substitutes for the SULFEX® additive, because chemical modification of bitumen by sulfonation requires special equipment, selection of bitumen and extensive experience. In this sulfonation process, a product is produced which has a high anionic activity and, as a rule, dissolves in water by 50-75%. Therefore, after the sulfonation of the additive SULFEX®, no longer has the chemical or physical properties of bitumen. The water-soluble part of the SULFEX® additive consists of large electronegative macromolecules. These particles in the filtrate are bound by the electropositive edges of clays and shales. This chemical neutralization prevents the natural tendency of the formation to accumulate water. Thus, slipping, swelling and destruction of shaly clay is prevented.
The fact that the SULFEX® additive has a high anionic activity gives it an undeniable advantage, giving it an undeniable advantage in identifying the electropositive shattered edges of shaly clay at the junction of the fracture and the wellbore. This neutralizes the destroyed edges and prevents the ingress of water into the formation. Chemically inactive substances, such as gilsonite, are distributed in solution only in chaotic order. Gilsonite contacts the surface when the solution seeps into the fissure, leaving a solid fraction, including gilsonite, at the junction of the fracture and the wellbore.
The SULFEX® additive technology and particle size provides an advantage over gilsonite, which is crushed to a size giving relatively coarse particles similar to the particles of crushed bitumen mentioned above. Virtually all particles of the SULFEX® additive, regardless of the size, feature high anionic activity. When the fractional composition of the particles is combined with the fact that the particles are highly charged and therefore reveal the shattered edges of the shaly clay, it becomes apparent that the SULFEX® additive provides a significant advantage over such products as gilsonite.
The SULFEX® additive successfully helps to control liquid loss, and especially filtration under high pressure and high temperature. During laboratory tests, gilsonite is ineffective in reducing mud filtration at high pressure and high temperature, and in some tests it actually increased filtration at high pressure and high temperature above the reference level.
The stabilizing characteristics of the SULFEX® additive (sulphonated asphalt), its ability to reduce filtration at high pressure and high temperature and to increase the lubricity, to prevent the adherence of the rock to the bit, to reduce the torque and tightening , and to help prevent stuck pressure from the pressure drop are good reasons for the use of SULFEX® additives. A particular combination of the chemical and physical activity of the SULFEX® additive definitely ensures its high efficiency.
The addition of SULFEX® (sulphonated asphalt) to the drilling mud remains in it, because it is sulfonated. Non-reactive competitive materials such as gilsonite and oxidized bitumen require the use of surfactants to prevent their emergence. In addition, non-reactive materials will agglomerate when there is an oil or hydrocarbon condensate in the system, which will cause them to float on the surface of the wells or exit above the shaker, grabbing useful materials like polymers. Such a costly loss of additives can be avoided by using the SULFEX® additive.
