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ENORDET product range & applications

We offer two main product lines: alcohol alkoxy sulfates (AAS) and internal olefin sulphonates (IOS). Find out more about the characteristics of each range.

 
Oil field

Currently, we offer two main product lines: the alcohol alkoxy sulfates (AAS) and the internal olefin sulphonates (IOS). Blending these different surfactants in various ratios allows the Alkaline Surfactant Polymer solution to be matched to the reservoir conditions, so achieving optimal EOR performance.

The benefits of each surfactant type can be summarised as follows:

Summary of surfactant's benefits
IOS     
  • can be used in reservoirs up to approximately 200°C
  • limited di-valent ion (eg Ca2+, Mg2+) tolerance, however, blended with AAS surfactants, this tolerance can be significantly improved
AAS
  • excellent di-valent ion tolerance
  • can be used in reservoirs up to approximately 60°C, slightly higher in an alkaline environment

For both groups, the molecular structure has been tailored to work at different reservoir salinities and with different crude oil types. Combinations of ENORDET* surfactants work in complementary ways Choosing the correct combination will help to prevent the formation of high micro-emulsion viscosities and gel-phases, which may otherwise hamper efficient transport of oil through the reservoir pores.

Sometimes, the use of a co-solvent (such as IBA or SBA) in combination with ENORDET surfactants can help in reducing micro-emulsion viscosities and so improve the sweep efficiency and oil recovery.

Key data for popular ENORDET surfactants

Key data for popular ENORDET surfactants
ENORDETTM Surfactant type Carbon number chain length Applicable salinity PO/EO per alcohol unit (mol/mol) Applicable temperature range Di-valent ion tolerance
O242 IOS C20-24 low/med N/A ambient to 200°C limited
O332 IOS C15-18 high N/A ambient to 200°C limited
O342 IOS C19-23 medium N/A ambient to 200°C limited
O352 IOS C24-28 low N/A ambient to 200°C limited
A771 AAS C16-17 low/med 7 PO ambient to ≥ 60°C excellent
A031 AAS C16-17 med/high 3 EO ambient to ≥ 60°C excellent
J771 AAS C12-13 low/med 7 PO ambient to ≥ 60°C excellent
J11111 AAS C12-13 low/med 11 PO ambient to ≥ 60°C excellent
J13131 AAS C12-13 low/med 13 PO ambient to ≥ 60°C excellent
J071 AAS C12-13 very high 7 EO ambient to ≥ 60°C excellent

Notes

  1. IOS: internal olefin sulfonate
  2. AAS: alcohol alkoxy sulfate, or alkyl ether sulfate
  3. Applicable salinity:  the range of salinities where a surfactant can be applied is formulation dependent
  4. Applicable temperature range: for the AAS, up to 60°C for SP formulations, slightly higher for ASP formulations
  5. Di-valent tolerance: effective di-valent ion tolerance is formulation dependent

Concentrated ENORDET surfactants

Sometimes, it is preferable to ship concentrated surfactants, minimising transport costs and reducing storage space. Depending on the concentration and surfactant type, the ENORDET surfactants can range in physical properties from low viscosity liquids to higher viscosity pastes.

To simplify operations in the field, it may be better to ship the surfactant system as a concentrated blend rather than ship the single surfactants. This has the advantage of only needing one surfactant storage tank and there is no need for surfactant mixing on-site. An additional benefit is that a combination of IOS and AAS surfactants often results in a lower viscosity liquid, which is easier to handle than a paste.

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