Application of Defoamers in the Petroleum Industry

I. Introduction

The petroleum industry is a vital component of modern industrial systems, encompassing multiple stages including exploration, extraction, refining, storage, and transportation. During these production processes, factors such as mechanical agitation, chemical reactions, and pressure variations often generate substantial foam. This foam not only impacts production efficiency but may also pose safety hazards. As specialized chemical additives, defoamers for the petroleum industry effectively control foam during production, playing a critical role in ensuring operational continuity, safety, and economic efficiency.

II. Foam Formation and Its Hazards in the Petroleum Industry

(1) Causes of Foam Formation

1. Crude oil extraction: Drilling fluids, fracturing fluids containing surfactants used in drilling, completion, and production operations readily generate foam.

2. Oil-gas separation: During three-phase separation of oil, gas, and water, sudden pressure drops and mechanical agitation create stable foam.

3. Crude oil refining: High temperatures and chemical reactions in distillation units, catalytic crackers, and cokers produce foam.

4. Petroleum product storage/transportation: Mechanical mixing and additives during loading/unloading and blending operations generate foam.

(2) Hazards of Foam

1. Reduced production efficiency: Foam occupies equipment capacity, decreases processing capability, and prolongs production cycles.

2. Compromised product quality: Foam introduces gas into products, affecting performance specifications.

3. Increased energy consumption: Foam reduces fluid density, raising pumping and separation energy costs.

4. Safety risks: Foam may cause false level readings, equipment overflow, and even safety incidents.

5. Environmental pollution: Foam overflow contaminates work environments and increases treatment costs.

III. Classification and Characteristics of Petroleum Industry Defoamers

(1) Classification by Application Stage

1. Drilling defoamers:

   • Primarily control drilling fluid foam

   • Require heat, salt, and shear resistance

   • Common types: Polyether-modified silicone oils, fatty alcohols

2. Production defoamers:

   • Control foam in oil/gas wells

   • Need high pressure/temperature resistance

   • Typical products: Fluorosilicones, polyethers

3. Refining defoamers:

   • Suitable for high-temperature processes like distillation/cracking

   • Require excellent thermal stability

   • Main types: Silicone-based, composite

4. Storage/transport defoamers:

   • Control foam in refined products

   • Must demonstrate good product compatibility

   • Common varieties: Non-silicone, polymer types

(2) Classification by Chemical Composition

1. Silicone defoamers:

   • Main component: Polydimethylsiloxane

   • Characteristics: Low surface tension, strong defoaming

   • Advantages: Low dosage, high efficiency

   • Disadvantages: May affect downstream processing

2. Polyether defoamers:

   • Main component: EO/PO copolymers

   • Characteristics: Heat resistance, persistent foam suppression

   • Advantages: Suitable for high-temperature environments

   • Disadvantages: Less effective at low temperatures

3. Fluorinated defoamers:

   • Primary component: Fluorinated compounds

   • Characteristics: Extremely low surface activity

   • Advantages: Effective under extreme conditions

   • Disadvantages: Higher cost

4. Composite defoamers:

   • Combination of multiple active ingredients

   • Characteristics: Comprehensive performance

   • Advantages: Wide applicability

   • Disadvantages: Complex formulations

IV. Application Examples in Petroleum Industry

(1) Drilling Operations

Key applications:

1. Controlling foam in water-based drilling fluids

2. Preventing density reduction in foam drilling fluids

3. Improving drilling fluid circulation efficiency
   Typical dosage: 0.1%-0.5%

(2) Oil-Gas Separation

In three-phase separators:

1. Eliminating stable foam

2. Enhancing separation efficiency

3. Reducing gas carryover losses
   Application methods: Continuous injection or intermittent addition

(3) Crude Distillation

In atmospheric/vacuum distillation units:

1. Controlling foam in crude/distillation columns

2. Preventing column flooding incidents

3. Improving distillate yields
   Injection points: Typically before feed entry

(4) Catalytic Cracking

In FCC units:

1. Controlling fractionator foam

2. Reducing hydrocarbon carryover

3. Increasing light oil yields
   Key requirement: High temperature resistance

V. Selection Criteria for Petroleum Defoamers

1. Specificity: Match specific process conditions

2. Compatibility: No adverse reactions with systems

3. Efficiency: Low dosage with significant effects

4. Safety: Non-toxic, non-contaminating

5. Economy: Optimal cost-benefit ratio

VI. Development Trends

1. Multifunctionality: Combining defoaming with corrosion inhibition etc.

2. Environmental friendliness: Biodegradable, low-toxicity

3. Smart technology: Developing responsive defoamers

4. Specialization: Products tailored for specific processes

VII. Conclusion

Petroleum industry defoamers play essential roles throughout oil production processes. As the industry advances into deepwater, ultra-deep wells, and heavy oil processing, performance requirements for defoamers continue escalating. Future petroleum defoamers will evolve toward greater efficiency, environmental compatibility, and multifunctionality, providing robust support for safe and efficient petroleum production. Operators should scientifically select defoamers based on specific process characteristics while continuously optimizing application protocols to achieve optimal techno-economic outcomes.