Glycol Ester Polyether: A High-Performance Demulsifier for Oilfield Crude Oil Treatment
1. What is an Oilfield Demulsifier?
In petroleum production and processing operations, the formation of stable water-in-oil (W/O) or oil-in-water (O/W) emulsions presents significant challenges to efficient crude oil treatment, transportation, and refining. These emulsions are stabilized by natural surfactants such as asphaltenes, resins, naphthenic acids, and fine solid particles that accumulate at the oil-water interface, creating mechanically robust films that resist phase separation. The presence of these emulsions leads to numerous operational difficulties including increased transportation viscosity, higher energy consumption for pumping, accelerated pipeline corrosion due to water entrainment, and reduced efficiency in downstream refining processes. To address these challenges, specialized chemical compounds known as demulsifiers are employed to destabilize the interfacial films and promote rapid coalescence of dispersed water droplets, thereby facilitating efficient oil-water separation.
Demulsifiers function through multiple mechanisms including interfacial tension reduction, displacement of natural surfactants from the oil-water interface, flocculation of water droplets, and film drainage promotion between droplets. The effectiveness of a demulsifier depends on its molecular architecture, which must be carefully designed to match the specific emulsion characteristics of the crude oil being treated. Among the various classes of demulsifiers, glycol ester polyether has emerged as a particularly effective solution for challenging emulsion systems due to its unique combination of hydrophilic and lipophilic properties, temperature stability, and compatibility with other production chemicals.
2. What is Glycol Ester Polyether Oilfield Demulsifier?
Glycol ester polyether represents a class of non-ionic surfactant demulsifiers synthesized through the esterification of polyhydric alcohols (such as ethylene glycol, propylene glycol, or glycerol) with fatty acids followed by alkoxylation (typically ethoxylation or propoxylation) to create a polyether chain. This molecular architecture provides an optimal balance between hydrophilic and hydrophobic properties, making it particularly effective in breaking stubborn emulsions found in heavy crude oils and high-salinity production systems. The chemical structure typically consists of three key components: a hydrophobic fatty acid ester group that anchors the molecule at the oil-water interface, a polyhydric alcohol core that provides structural stability, and hydrophilic polyether chains that extend into the aqueous phase to disrupt the emulsion stability.
The general chemical structure can be represented as:
[R-COO-(CH₂-CH(R')-O)_n-H]
Where:
R = Alkyl chain (typically C12-C18 from fatty acids)
R' = H (for ethylene oxide) or CH₃ (for propylene oxide)
n = Degree of polymerization (typically 5-20)
This molecular design confers several critical properties that make glycol ester polyether particularly effective as an oilfield demulsifier:
Temperature stability up to 150°C, making it suitable for thermal recovery operations
Salinity tolerance due to the non-ionic nature of the polyether chains
Adjustable HLB (hydrophilic-lipophilic balance) through variation of the alkoxylation degree
Low toxicity compared to phenolic or amine-based demulsifiers
Excellent compatibility with other production chemicals such as corrosion inhibitors and scale inhibitors
3. Applications of Glycol Ester Polyether in Oilfield Operations
Glycol ester polyether demulsifiers find extensive application across various stages of crude oil treatment, demonstrating particular effectiveness in several key areas:
Crude Oil Dehydration: In primary separation facilities, glycol ester polyether is particularly effective in breaking water-in-crude oil emulsions, achieving rapid water drop and clean oil specifications. Its performance is especially notable in heavy crude oil applications where the presence of asphaltenes and resins creates particularly stable emulsions. Field applications have demonstrated that properly formulated glycol ester polyether can reduce BS&W (basic sediment and water) content to less than 0.5% in many cases.
Desalting Processes: In refinery crude oil desalters, glycol ester polyether serves as an effective desalting aid when used in combination with cationic demulsifiers. The polyether chains help solubilize inorganic salts and promote their transfer to the aqueous phase, while the ester groups help maintain good oil phase separation. This dual functionality makes it particularly valuable in processing high-TAN (total acid number) crude oils.
Thermal Recovery Operations: For steam-assisted gravity drainage (SAGD) and cyclic steam stimulation (CSS) operations, where produced fluids often exceed 100°C, glycol ester polyether maintains its demulsification efficiency better than many conventional demulsifiers. Its thermal stability prevents degradation and maintains performance throughout the high-temperature processing chain.
Offshore Applications: The combination of salinity tolerance and effectiveness at low dosages (typically 10-50 ppm) makes glycol ester polyether particularly suitable for offshore applications where chemical storage and handling space is limited. Its effectiveness in deepwater operations with high pressure and low temperature conditions has been well documented.
Table 1: Performance Comparison of Glycol Ester Polyether vs. Other Demulsifier Types
4. Application Methods of Glycol Ester Polyether Demulsifier
The effective deployment of glycol ester polyether demulsifiers requires careful consideration of application methods, dosage optimization, and potential synergies with other treatment chemicals:
Bottle Testing Protocol: Prior to field application, comprehensive bottle testing is conducted to determine optimal formulation and dosage. This involves:
Preparing representative crude oil samples with native emulsion characteristics
Adding demulsifier at varying concentrations (typically 10-100 ppm)
Subjecting samples to controlled heating (usually 50-70°C) and settling periods
Measuring water drop rates and interface quality
Evaluating oil dryness and water clarity
Injection Methods: Field application typically employs one of several methods:
Continuous Injection: The most common method, where demulsifier is injected upstream of production separators at carefully controlled rates. Injection points are typically located at wellheads, manifold stations, or upstream of free water knockouts.
Batch Treatment: Used for problematic wells or during upsets, where a concentrated slug (100-500 ppm) is introduced to the system.
Combination Treatments: Often used with:
Cationic demulsifiers for improved salt removal
Solvents (e.g., xylene) for heavy oil applications
Reverse breakers for oil-in-water emulsions
Dosage Optimization: Key considerations include:
Crude oil API gravity and viscosity
Water cut percentage
Temperature and pressure conditions
Presence of production chemicals (e.g., corrosion inhibitors)
System residence time
Monitoring and Adjustment: Continuous monitoring of separator performance, BS&W levels, and interface quality allows for real-time adjustment of demulsifier programs to maintain optimal performance as field conditions change.
5. Pricing and Economic Considerations of Glycol Ester Polyether Demulsifier
The market price of glycol ester polyether demulsifiers is influenced by several factors including raw material costs, production complexity, and market demand. Current pricing (2025) ranges from 5.00to12.00 per kilogram, with several key economic considerations:
Cost Drivers:
Ethylene Oxide/Propylene Oxide Prices: Fluctuations in these key raw materials significantly impact production costs. Recent market prices for EO have ranged from 1,200−1,800/ton.
Fatty Acid Feedstock Costs: Derived from vegetable oils (palm, soybean) or tall oil, with prices typically between 800−1,500/ton.
Manufacturing Complexity: The multi-step synthesis (esterification followed by alkoxylation) contributes to higher production costs compared to simpler demulsifiers.
Economic Justification:
Despite higher unit costs compared to conventional demulsifiers (alkylphenol resins at 3.50−7.00/kg), glycol ester polyether offers compelling economic advantages:
Lower Dosage Requirements: Typically 30-50% less product needed compared to conventional demulsifiers
Reduced Energy Costs: Faster separation reduces heating requirements in treaters
Improved Crude Quality: Higher value crude with lower BS&W and salt content
Extended Equipment Life: Reduced emulsion carryover minimizes fouling in downstream equipment
Market Trends:
Increasing demand for heavy oil treatment chemicals
Growing preference for environmentally acceptable chemicals
Development of customized formulations for specific field conditions
Expansion of production capacity in Asia and Middle East
When evaluating total cost of ownership, glycol ester polyether demulsifiers often prove more economical than initially apparent due to their superior performance characteristics and lower effective treatment costs. Many operators have found that despite higher upfront costs, the overall chemical program costs are reduced through optimized treatment rates and improved operational efficiency.
In conclusion, glycol ester polyether represents a technologically advanced and economically viable solution for modern oilfield emulsion challenges, offering superior performance across a wide range of operating conditions while meeting increasingly stringent environmental and operational requirements.
Glycol ester Supplier
UNPChemicals is a professional oilfield chemical manufacturer, with products covering drilling, completion, oil production, gathering and transportation, etc., and has won the trust of customers with advanced technology, strict quality control and high-quality services. We are committed to personalized solutions to help oilfields develop efficiently.