To produce greater oil and gas, to solve the creation of mineral substances like CaCo3, MgCo3 and to increase the efficiency of the production, acids in different forms (HCl and HF) are injected into the generating well of hydrocarbons, this acid compound because of its role and goal has corrosion intensifier and inhibitor, iron control additive, surfactant, and solvent. Insolvable parts, the sediment of crude oil reaction with an acid solution, are named sludge. Resin, paraffin, asphaltene, malten and hydrocarbon with different molecular weight, all are in crude oil and can have chemical reactions with acids, so as a result, blocking precipitate creates. Before injection the aqueous acidic solution for treatment in well, anti-sludge agent, which can contain a cationic surfactant, dodecyl benzene sulfonic acid, corrosion inhibitor, iron reducing agent and other additives, applied to the compound.
Materials List – Drilling
PAC
Coagulation process has a special place in the Purifier industry. Aluminum sulfate and ferric chloride is the most common primary coagulant are used in water treatment to remove turbidity. In recent years, Poly Aluminum Chloride – which briefly called PAC-a widely used as a replacement for the old two-coagulant, aluminum sulfate, and chloroferric. Now a day, PAC in countries such as America, Canada, China, Italy, France, and England is used as one of the most common coagulants in water purification and waste water treatment. In Iran, many industries use this material as an alternative coagulant.
Poly Aluminium Chloride presented in both liquid and solid which Solid aluminum chloride is in the form of powder or crystal and their color are in different ranges from milky white to dark yellow.
PAC is used in lots of industries such as oil industry.
PAC is an inorganic polymer which its monomer is a dual-core complex of aluminum.
Xanthan Gum
Xanthomonas Campestris bacteria secrete a polysaccharide known as an XC polymer. In places and applications are environmentally sensitive, the safe and appropriate gum for usage is Xanthan gum. In PH, temperature and mineral contaminant changes do not affect the xanthan gum properties which is mud additive with great efficiency and product with environment-friendly features. Trustworthy replacing and moving control factor is the result of xanthan gum temperature resistance features.
Because of acetyl and pirovyl groups, xanthan is an ionic polysaccharide. These molecules are highly ionized in water and ionic charge distribution in the molecule due to escape ions leads to the formation of extensive molecular form.
In the oil industry, this kind of gums is wide usage and much more for thickening the drilling mud. In the low shear, the unique high viscosity of xanthan gum can support drilling fluid low concentration. In low shear situations, the critical point is solid suspension where low end rheology created by Xanthan gum. A much stable viscosifier for fresh and brine drilling fluids comes from Xanthan gum. Xanthan Gum of Drilling Grade is the best production for oil and gas drilling exploration usage. Xanthan Gum can use to increase Oil Recovery. Unique rheological features of xanthan gum bring a highly uses as a viscosifier for various usages.
Guar Gum
An insipid yellowish white gum powder comes from guar plant seed known as a hydrophilic polysaccharide is thermally unstable, high PH sensitivity and bacterial fermentation. Guar gum is widely used because it spread and hydrate fast in hot and cold water.
In Oil and Gas well drilling widely used Guar gum for increasing oil and gas production rate. Guar gum makes a better colloid in well-drilling mud and as a result water mortality reduction, mud solution viscosity regulation, drilling mud flow properties stabilization and regulation. Guar gum is used in the hydraulic fracturing process in raw oil production and as an oil & gas drilling well sealant.
The kinds of additives used in a process are widely dependent on the drilling process performance and accuracy. The drilling process performance increased by the usage of appropriate additives. In drilling fluids, as a thickening, stabilizing, and suspending factor, guar gum is widely used. For helping to balance drilling mud viscosity, the guar gum viscosity increaser feature is important. Increasing the fracture creation while the formation damage minimizing is the important goal of additive usage in fracturing fluids which helps to retain the need of high viscosities in the fracturing process of the oil well. To improve the fracturing liquid ability for proppant carrying, the powder form of guar gum is used in the fracturing of the oil well. The presence of colloid solid in guar gum effects the fracturing fluids effectiveness in filter production reduction and as a result wasting reduction.
Wide availability, low price, and natural sources, drilling industry always faced with environmental worries, are reasons why guar gum is selected among others.
A surfactant for drilling fluid (based on water and brine) rheological needs is suitable as a defoamer and synthetic polymer.
Corrosion Inhibitor
Chemical factors, preventing the process of damage to the material is their duty, creates a narrow protective membrane on the surface of the materials. Corrosion inhibitors are both inorganic and organic compounds. We can divide inhibitors by mechanism of action in 3 groups: cathodic, anodic and mixed cathodic-anodic. Environment PH is so important in their operation efficient. Another grouping for inhibitors according to their chemical nature are imidazoline, heterocyclic compounds which have one N, amines and ammonium salts, quaternary ammonium salts. Using of hydrophobic corrosion inhibitors is preferred by oil and gas industry.
Based on the using system, inhibitor divided in 3 group: soluble in water, soluble in oil and three-phase corrosion inhibitor. Vital point needed more attention in every step of oil and gas production is a prevention of corrosion. An important point for protecting internal corrosion of oilfield pipelines is appropriate corrosion inhibitors selection. Most of the corrosion difficulties in refineries happen because of inorganic materials like water, CO2, sulfuric acid, H2S, and sodium chloride. Corrosion engineers say corrosion is the result of being together water and steel. Oil and gas pipelines are widely created by carbon steel. Carbon steel near water, created raw oil or natural gas from underground reservoirs, corrodes.
Earlier corrosion inhibitor research just focused on the water phase but new research study about the crude oil phase on the corrosion inhibitors efficiency.
Stabilizing the PH in different gas systems is the way used in Iran in South Pars. The base of this way is using glycol. Iran can produce the inhibitors grouped based on systems.
H2S Scavenger
H2S is a highly toxic gas made from organic material decomposition and as an Unwanted product in Oil creation processes.H2S, in addition to causing intensive process equipment corrosion, is so toxic and make serious human and animal poisoning. The removing H2S process known as gas sweetening can happen in 2 methods: forming iron sulfide or chemical scavengers. Chemical materials based on amine are usual H2S scavengers in the oil industry classified in non-regenerative and regenerative H2S scavengers.
Regenerative H2S scavengers: Monoethanolamine, Diethanolamine, N-methyldiethanolamine, Diisopropylamine, Diglycolamine
Non-regenerative H2S scavengers: Triazine, Solid scavengers, oxidizing chemicals, Aldehydes, Metal carboxylates and chelates
Economics plays a major role in H2S removal process selection. Where the H2S level is less than 500ppm scavenger usage is the best economical selection and in more than 500ppm, another choice should use. The best selection with short term view if the capital cost can be minimized through continuing injection, is still using a scavenger for removing H2S high concentration.
In a wide range of usages, H2S scavengers can provide for successful treatment:
H2S removing from gas flows and sour hydrocarbon liquids, H2S reducing in sour liquid tank vapor area.
Foam Agent
Foaming agents, drilling liquid, added for foam preparing, at first, should have tolerated some bad conditions like hard water and solids, high brininess and temperature. Drilling foam, water including gas or air bubbles, is different from foaming agents which are polymeric materials and nonionic surfactants.
We can divide foam agents into 2 categories:
Super Foam: anionic surfactant biodegradable mixture for water well drilling and mineral industry
AMC HV Foam: new generation extremely condensed foam constants in great density in every kind of ground water situation
New researches show that stable foam agent can be used for controlling the CO2 mobility in oil recovery increasing.
Foam agent is used in oil industries for improving recovery in this aspects: drilling, fluid transportation for gas-condensate, gas and oil well, well development in low creation pressure, acidic treatment additives.
KCl
Metal halide compound of potassium and chloride is used in manures, hazardous and buffers. It has intense salty taste and white colorless solid with powdery, crystalline form. KCL is a hygroscopic compound dissolved in water and its solubility is increased in high temperature. Potassium is important for our health and its compound is widely used as a drug in health science.
KCL is the most important potassium salt compounds that exist as an ore in nature.
KCl is an ionic compound.
Potassium chloride has a lot of usages, like NaCl alternative in home water softener units and widely usage in oil and natural gas drilling but recently oil Drilling Companies had replaced Potassium Chloride (KCL) with Choline Chloride. The use of KCL in drilling has environmental concerns as chlorides do not degrade and can enter surface water carrying heavy metal including cadmium and mercury but Choline Chloride has not this bad effects. Potassium Chloride is a temporary clay stabilizer used for preventing the swelling of clay. A solvable salt that is an extremely effective shale stabilizer when drilling hydro sensitive clays and shales. Exchange create inhibition; the potassium ion enters between the individual clay platelets in the shale so that they are held together, so miss entry of water from the drilling fluid.
Usual oil well drilling chemicals:
- KCl
- BENTONITE
- BARITE
- Calcium Carbonate
- GUAR GUM POWDER
Benefits:
- Low price and easily available
- Advantages gotten at low concentrations
- Has harmonic with most drilling fluid additives
- Stabilizes water sensitive clays and shales
- Removes issues resulting from shale instability
- Fast solving
CMC
The reaction between natural cellulose and mono chloro acetic acid and sodium hydroxide create salt of CMC sodium. To control fluid loss can use a drilling fluid additive which name is carboxy methyl cellulose.
Carboxy methyl cellulose is in both as low and high-viscosity. The viscosity is mostly dependent on the starting cellulose molecular weight. It acts as an important factor in drilling mud quality improvement. High viscosity model is used to make concentration and low viscosity form used to make it as a factor in reducing the waste solution filtration in oil drilling. Controlling fluid loss, absorbing and retaining water, sealant wells, and soil suspenser.
CMC can use in this industries: Food and Beverages, Oil Field Drilling Fluids, Drugs and Cosmetics, Paper Processing Aids, Detergents, Paints & Coatings.
The drilling fluid element combination is so important in operation efficiency and success. The basis of drilling fluids is water because of environmental attentions. CMCs is a fundamental part to decrease fluid loss and plays a major role in the drilling fluid viscosity and the shale inhibitive features.
CMC is a white powder, odorless, suspended in water and under normal conditions non-fermented. The carboxy methyl cellulose is produced in the world at around 105 × 3 tons and over 300 different types with different degree of substitution and purity and rheological properties and used. Among the polysaccharides, carboxy methyl cellulose is the most available and much cheaper and has great stability. Important properties of carboxy methyl cellulose polymers are easy shipping, no effect on pH and suspension and large capacity of the mass formation.
Natural Gum
Natural gum is the kind of chemical drilling fluids, and drilling fluids used to control the fluid and water loss, to lubricate and to cool the drill bits, to inhibit shale , and to transport solids, to clean the hole bottom, to carry cuttings to the surface, to control formation pressures, and to improve the function of the drill string and tools in the hole, are mixtures of natural and synthetic chemical compound .guar gum and xanthan gum and cellulose derivatives as a natural polymers are used in well drilling of oil and gas. Drilling fluid is in 3 basic group which are water-based and non-aqueous mud and gaseous drilling fluid and their major roles are formation damage prevention and corrosion limitation.
Surfactant
Influencing surfaces and interface properties is the surfactant significant ability that is a reason why surfactant has numerous usage and can be in a lot of applications. To decrease surface tension or interfacial tension either among liquids or liquid and solid, chemical substances are used which absorbs the jointing and named surfactant. A lot of material can be in this category like dispersants, emulsifiers, foamers and defoamers and behavior of each kind of surfactant is widely dependent on molecule structural groups.
Surfactant categories:
- Anionic: with one or more negative charged, excellent detergent and the most usage of them is a laundry detergent.
- Cationic: with one or more positive charged, low detergency, good usage as germicides, cloth softeners, and emulsifiers.
- Amphoteric: with both anionic and cationic group and the characteristics of both, good function at neutral pH and exist in production like hair shampoo, skin cleaners, and carpet shampoo.
- Non-ionic: without ionic groups, with an extensive range of chemical features and usage.
De-emulsifier
Useful material for separation of water from crude oil emulsions. Stability of hydrocarbons material emulsion in water in the refinery sewage is the important problem that should solve by separating 2 phases. It means crude oil emulsion is broken into oil and water phases by the de-emulsifier. De-emulsifiers are used because of their high solubility in water.
Technical equipment helps us to find that three types of crude oil emulsion exist: oil-in-water, water-in-oil, and multiple emulsion. Different emulsions with different water ratio are created at different times. Action mechanism of de-emulsifier is substituting partially of the interfacial active materials and decreasing strength of the interfacial film.
Throughout the heating process of the oil-water solution, de-emulsifier is applied. The important point of de-emulsion usage amount depends on the type and viscosity of the oil wanted to separate.
Oil production, transportation, and processing can create water-oil emulsions. To improve the quality of oil should break this emulsion. New researches show microbial de-emulsifiers can be a potential replacement to the chemicals.
Iran, at the end of hard working and studying on this subject, finally found the ways to produce de-emulsifier, this important material for Iran’s most important product quality.
HCl
Other names: Hydrochloric acid; Hydrogen chloride; Muriatic acid; Chlorohydric acid; Acide
HCl vapors fast and greatly that make serious and pungent odor and can be harmful to lung, eye, and skin.
Solving hydrogen chloride in water create a strong corrosive acid which is colorless liquid with strong irritating odor and stable in high temperature. One of the usages of HCl is in acid washing for cleaning rust, calcium carbonate, other sediments in the good path (oil well acidizing) and oil- and gas- well stimulation. HCl performs extensive situation in the formation of carbonate and hydraulic breaking process.