Glycolic acid, a versatile hydroxyacetic acid from PureTech Scientific, has been increasingly used in the oil and gas industry due to its unique properties that enhance various operational processes. It is known for its effective cleaning, corrosion inhibition, and scale-removal capabilities.
In oil and gas, it plays a crucial role in wellbore cleaning and descaling and as a component in chemical blends that prevent or remove buildup in pipelines and equipment. Its organic-acid nature makes it less corrosive to metal than stronger acids, offering a safer, more sustainable alternative for managing scale deposits and corrosion and improving flow assurance.
Glycolic Acid 70% Technical Grade provides enhanced efficiency, reduces equipment wear, and can improve environmental compliance in an industry where precision and sustainability are increasingly prioritized.
Oil and Gas Applications
Glycolic acid is used for several oil and gas applications, most notably in acidizing, rehabilitation, and finishing.
In the process of acidizing, glycolic acid is introduced into oil wells to dissolve rock and minerals, effectively enhancing the permeability of the formation. This increase in permeability subsequently boosts the flow of oil and gas, making extraction processes more efficient.
Acidizing to Form Glycolate Salts
Aqueous Solubility of Glycoalte (Hydroxyacetates) Metal Complexes
Metal
Temperature (°C)
Solubility, wt%
Na
20
40.9
K
20
56.6
Mg
18
28
60
100
7.3
7.7
10.8
23.0
Ca
17
28
60
100
1.2
1.5
3.8
4.4
Pb
15
100
20.6
3.3
Zn
20
3.3
Ref: US6695968 'Removal of Water Soluble Organics', 2004, Baker Hughes Incorporated
During the rehabilitation of wells, glycolic acid plays a critical role in cleaning and removing rust, scale, and other particulates that accumulate over time, which might hinder production. Its ability to form soluble salts with metal ions ensures that these unwanted materials can be easily flushed from the wells.
In terms of finishing, glycolic acid is utilized to prepare the well’s surface for further use, ensuring that the structure remains effective and reliable throughout its service life.
The multifunctional nature of glycolic acid makes it an indispensable tool in the oil and gas industry.
Benefits of Glycolic Acid
High water solubility
Low odor, low corrosiveness
Efficient pH adjuster
NSF/ANSI Standard 60 certified
For use in potable water systems
Biodegradable (90% in 7 days)
Solubilizes hard water salts Ca, Mg, Fe
Nonvolatile, very low vapor pressure
Low toxicity; LD50 for rats = 1938 mg/kg
VOC exempt in California
The following properties contribute to glycolic acid’s effectiveness and versatility for applications in the oil field industry:
It chelates rust, scale, and particulates found in wells.
When glycolic acid complexes with metal ions, it forms a soluble salt, which can be easily pumped from the well.
It has lower corrosivity to most metals as opposed to mineral acids. Corrosion testing should be performed on the construction materials prior to use.
It has good acidification properties to decompose carbonates.
This acid additive is compatible with other acids and additives.
Glycolic acid formulation is available for industrial boiler cleaners; it focuses on utilities to clean boilers fouled with various scales.
Low Corrosiveness
Glycolic Acid 70% Technical Grade ensures economical cleaning by providing low-cost metal complexing in a readily biodegradable form that will not add potentially undesirable biological oxygen demand (BOD) or chemical oxygen demand (COD) to formulated products. It can be used with hydrochloric and sulfamic acids to prevent iron precipitation in cleaning operations and water flooding. NSF certified with low odor, low vapor pressure, and nonflammability, glycolic acid can effectively eliminate harmful deposits while minimizing corrosion damage, all with safety in handling and ease of use. Glycolic acid is less corrosive than other competitive NIK acids on common metals.
Percent Weight Loss at 70°C
Metal
Glycolic
Lactic
Phosphoric
Sulfuric
HCI
C1018
10.53
8.84
15.70
39.08
53.22
AL1100
0.38
0.31
19.94
10.90
51.75
SS304
0.008
0.007
0.007
2.360
15.220
SS316
0.002
0.002
0.002
1.600
18.460
Cu110
0.045
0.044
0.086
0.095
0.310
CDA360
0.061
0.056
0.081
0.067
0.170
Galv. CS
15.50
20.33
83.81
100.00
100.00
Immersed in 200 ml of solution for 48 hours. No agitation. Results are the average of triplicate analysis, 10% acid (100% basis)
Complexing Ability
Glycolic acid utilizes both its hydroxyl and carboxylic functional groups to create five-member ring complexes with polyvalent metals, a unique chemical property that significantly enhances its effectiveness. This is particularly beneficial when dealing with scale and rust that commonly accumulate in oil wells and pipelines, as it aids in dissolving these deposits, enabling easier removal. The formation of these stable ring structures not only ensures efficient binding with metal ions such as calcium, magnesium, and iron but also helps in reducing the corrosive impact on metal surfaces. This can prolong the lifespan of equipment, lower maintenance costs, and improve overall operational efficiency.
Furthermore, the ability to chelate and solubilize metal ions makes glycolic acid an invaluable component in formulating industrial cleaning agents designed to tackle tough scales and deposits in high-demand environments like the oil and gas sector.
CaCO2 Scale Removal Efficacy
Time (min)
Glycolic Acid (g/kg)
Citric Acid (g/kg)
Gluconic Acid (g/kg)
Lactic Acid (g/kg)
Phosphoric Acid (g/kg)
Sulfuric Acid (g/kg)
EDTA-Sodium (g/kg)
0
0
0
0
0
0
0
0
15
223
201
56
110
202
272
58
30
347
310
88
222
297
386
87
60
463
323
139
319
405
470
137
120
554
323
178
397
489
505
193
240
603
323
211
445
514
512
225
300
612
323
222
447
521
510
237
Minutes = Exposure Time Grams of calcium carbonate per kg of chelant