Oil & gas well stimulation using acidizing and acid stimulation processes
Well stimulation materials: extending the life cycle of oil & gas production
As new sources of oil & gas become increasingly difficult to access, oilwell stimulation has become a key leverage to increase the capacity of existing wells and prolong their production life cycles. These techniques seek to increase the flow of oil & gas by opening new channels to efficiently direct all available resources from the production area into the wellbore. This makes existing wells more cost effective and profitable, but also enables idle wells that were no longer feasible to restart production to meet growing demand. This is crucial in increasing supply while new sources are being explored and developed. Elkem offers a full oil & gas stimulation product portfolio, expert advice and a laboratory to support customers in analysing reservoir characteristics and their potential.
Elkem oilwell stimulation products focus on acidizing and acid stimulation.
In acid stimulation the objective is to remove or bypass damage:
- In sandstones, to restore natural permeability.
- In carbonates, to create a highly conductive flow system that bypasses damage to yield a higher production rate than that obtained in the natural, or undamaged, state.
We do this by accurately diagnosing the damage through mineralogy studies to help identify the type of harm: mineral or organic.
Once the damage is identified, a well treatment fluid is designed to deal with the problem. The Elkem Oil EOC stimulation portfolio offers a wide range of chemicals tailored to treat these damages.
Elkem also performs core sample testing to decide on the most effective options to stimulate oil & gas production.
Ensuring results in oilwell and gas stimulation
The Elkem Oilfield portfolio includes a comprehensive, efficient, cost-effective and safe range of chemicals and fluid systems to stimulate and enhance well production. This includes tailored mixes, new technologies and support services to help customers meet specific challenges.
The Elkem Oilfield R&D laboratory in Kristiansand, Norway is dedicated to creating new products upstream and to provide advice and expertise on daily operational challenges throughout the oil & gas industry.
Here is an overview of products available to help customers meet specific challenges:
- Acid Corrosion Inhibitors and Intensifiers are used to reduce the corrosion rate of metals and extend their lifetime. These surface-active agents protect pipes, radically slowing down corrosion by reducing the reaction rate of acid with iron and steel, known as pitting. Other additives, such as surfactants and mutual solvents, are boost long-term protection.
- Self Diverted Acid Additives are gelling agents used to acidize damaged perforations, by enabling greater fracture penetration, slowing reaction rate, and reducing fluid loss, improving acid coverage and increasing production and permeability.
- AGA-100, an acid gelling agent that improves the effectiveness of matrix and fracture acidizing treatments and provides improved viscosity and thermal stability to enhance acid treatment in carbonate formations.
- HEC-10 is a linear, non-ionic, polymer used in viscosifying water-based fluids in well stimulation, coiled tubing, cleaning, completion and workover operations.
- XG-100 is a gelling agent for suspending weighting agents in space systems, effective over a wide range of bottom hole circulating temperatures (BHCT).
- VES-1000 is a polymer-free, surfactant-based acid gellant designed for use in self-diverting acidizing applications.
- Guar Gum Grade 35 is a chemically modified low-residue guar gelling agent used in aqueous fracturing fluids, effective at bottom hole circulating temperatures (BHCT)
- Iron Control Agents are products that eliminate Fe(III) ions either by a sequestering and complexing process or by a reduction process.
- ICE-100 and ICE-100L CE-100 and ICE-100L are the solid and liquid versions of Elkem Oilfield iron control agents, designed to maintain a low pH throughout the acid treatment period, acting as complexing agents.
- ICE-200 and ICE-200L are solid and liquid organic iron-sequestering agents for sour applications used in acidizing applications in water injection wells to prevent precipitates and potential plugging when high concentrations of iron oxides are present.
- Specialty Surfactants are oil-soluble group or water-soluble surface-active agents that lower the interfacial tension between immiscible fluids and can alter the natural wettability of rock.
- Specialized Solvent Systems are soluble in oil or water and are very effective in sandstone acidizing, where it is important to keep all solids water-wet. They improve the solubility of corrosion inhibitors in the spent acid in the formation and, with emulsion preventers and other additives, they absorb of corrosion inhibitors on residual clay particles to help maintain water-wetting for maximum oil & gas flow after acidizing, facilitating cleaning.
Our experts and dedicated service teams are always available to support you, discuss technical information and processing issues and provide samples and quotes. Please feel free to get in touch.
See below for an overview of our portfolio.
Acid corrosion inhibitors and intensifiers
ACI-60 is a high temperature acid corrosion inhibitor used primarily in well stimulation projects at temperatures up to 350 °F (177 °C). It can either be batch mixed or added on the fly. Dosage concentrations are temperature dependent and vary based on the type, temperature, acid concentration and severity of the corrosion problem.
In high temperature wells, ACI-2X is added to acid formulation to extend the temperature range of most corrosion inhibitors - up to 350 °F (177 °C). When used with normal hydrochloric and hydrofluoric acid, the product improves the corrosion protection at elevated temperatures on most steel grades.
ACI-50 is an efficient universal acid inhibitor for use in hydrochloric acid and in formulations which combine hydrochloric acid with others, such as acetic, formic or hydrofluoric acid. It provides effective protection of tubulars and downhole equipment in bottom hole temperatures to 250 °F (121 °C). It is very dispersible in all acid-based fluids, and compatible with most common acidizing additives.
Iron control agents
ICE-100L is an iron-sequestring agent in acidizing applications. ICE-100L is effective in both organic and inorganic acid-based applications at elevated temperatures. It is especially useful if the treatment involves longer contact time of acid systems with key completion accessories.
ICE-200L is an organic iron-sequestering agent used in acidizing applications. ICE-200L is the preferred sequestering agent for sour applications. ICE-200L is not a reducing agent and will not help prevent iron induced sludge in crude oils. ICE-200L should not be used with hydrofluoric acid blends.
ICE-100 is an Iron Control Agent composed of trisodium salt and nitrilotriacetic acid. ICE-100 is effective in both organic and inorganic acid-based applications at elevated temperatures. It is especially useful if the treatment involves longer contact time of acid systems with key completion accessories.
ICE-200 is polydentate ligand molecules that makes stable and water-soluble complexes with metal cations. These molecules bind the Fe (III) ions and make them unreactive to other chemical reactions.
Self diverted acid additives
AGA-100 is designed to improve the effectiveness of matrix and acid fracturing treatments. It provides improved viscosity and the thermal stability of the gelled acid system to enhance the acid treatment results in carbonate formations. AGA-100 is based on synthetic polymer chemistry that will effectively gel all concentrations of hydrochloric acid, hydrochloric-hydrofluoric acids and organic acids.
Guar Gum 35 low-residue guar gelling agent used in aqueous fracturing fluids can be batch-mixed or mixed continuously. It is effective at bottom hole circulating temperatures (BHCT) up to 200 °F (93.3 °C).
VES-1000 is a polymer free, surfactant-based acid gellant designed for use in self-diverting acidizing applications in oil and gas wells.
XG-100 is a gelling agent for suspending weighting agents in spacer systems.
HEC-10 is a linear, non-ionic, polymer used in viscosifying the water-based fluids used in well stimulation, coiled tubing, clean-outs, completions and workovers operations. Its main purpose is to provide a stable fluid and prevent settling. It is also used as foam stabilizer in water-based foam fluids.
FR-100 is a chemical additive that alters fluid rheological properties to reduce friction within in the fluid as it flows through small diameter tubular or similar restrictions.
NEA-80 is general product for a wide variety of crudes, including asphaltic oils.
ASW-100 is a blend of cationic surface-active agents used as a non-emulsifier and antisludging agent in acid stimulation treatments. It prevents an emulsion forming by the acid and allows spent acid to return more readily. It is designed to avoid problems associated with crude oil sludge formation caused during acidizing operation.
SFT-50 is a non-ionic surfactant used to lower surface tension in acid formulations.
FOM-40 is an anionic surfactant based multi-purpose foaming agent designed primarily for foaming acid-based fluids. The product is extremely versatile, capable of providing stable foams in all water-based fluids.
HS0-100 is a polymeric hydrogen sulphide scavenger used in crude oil systems.
Specialized solvent systems
SLV-80 is a multifunctional non-ionic agent that is soluble in oil and acid as well as fresh water and brines. SLV-80 is more effective than most surface active agents in water wetting, preventing emulsions and in minimizing particle plugging.