The term "stable condensate"

Stable condensate is a liquid mixture of hydrocarbons with the formula C15 H12 and higher, which have more than three or four carbon atoms in the molecule. The number of carbon atoms depends on the specification. Stable condensate is a liquid that is colorless or slightly colored, the relative density is from 0.72 to 0.78. This is a flammable product that is classified as a hazardous substance due to its toxicological properties. When combined with air, condensate vapors form an explosive mixture.

A stable condensate is obtained from the product, which releases natural gas. There is such a thing as unstable gas condensate, which is obtained by condensation under conditions of decreasing pressure or temperature natural gas. To transport gas condensate for processing using bulk transport, it is necessary to remove volatile fractions from it by rectification or keeping it for a certain time under conditions of atmospheric pressure and elevated temperature. It is after removing the volatile fractions that a stable gas condensate is obtained. The degree of removal of volatile fractions is checked and determined from the specifications for vapor pressure according to Reid for various containers (tanks, storage facilities). Thus, according to recommendations developed by the American Petroleum Institute, for market raw materials this indicator at a temperature of 15 degrees Celsius should not be more than 69 kPa. This indicator value is associated with excess pressure in vertical storage facilities. A higher Reid vapor pressure value is possible, but this will lead to evaporation of the raw material during storage from the breathing valves that are supplied to all tanks.

In nature, gas condensate in most cases is in a gaseous state as a composition of slightly lighter hydrocarbon gases. If pressure or temperature drops below a certain value, the so-called critical value, the process of reverse condensation begins. Reverse condensation stops the process of extracting condensate outside, which is explained by the higher permeability of rocks to gas than to liquid hydrocarbons. But at the same time, the condensate accumulated in the rocks worsens their gas permeability. To avoid reverse condensation and condensate loss during this process, the internal pressure and permeability to gas and liquid hydrocarbons are increased in the formation. There is a cycling process, which consists of injecting partially stripped gas into the formation in order to maintain in-situ pressure above the maximum pressure at which any of the phases of the multicomponent system will be in a state of equilibrium.

Stable gas condensate is used to produce motor fuels, as well as in the chemical industry.

Stable condensate comes in two types – dark and light. It depends on such factors: where it was extracted from, from what depth the extraction took place. It is because of the difference in these factors that the color changes depending on the content of impurities - from brown to light yellow.

Considering that stable condensate is a rather dangerous product, safety requirements must be strictly observed when interacting with it. Thus, workers carrying out its collection and drainage must wear personal protective equipment. All equipment for stable condensate must be tested for leaks. For small fires, foam fire extinguishers and sand are used to extinguish. In case of larger fires, mechanical or chemical foam, as well as water, are used.

Companies whose news contains stable condensate:

Reservoir products from a number of fields, along with gaseous components, also contain pentane and heavier hydrocarbons (C 5+). According to the static reporting form 34 TP, C 5+ hydrocarbons are usually called gas condensate. In practice, the term stable condensate is also used. This product, along with C5+ hydrocarbon, also contains propane, butane and other compounds. Stable condensates meet the requirements of GOST 51.60-80.

Some condensates have a pronounced methane character (Markovskoye), while others are dominated by naphthenic hydrocarbons (Ustye-Chesalskoye, Bovanenkovskoye). Some condensates contain significant amounts of aromatic hydrocarbons. For example, in the condensates of the Mitrofanovskoye, Nekrasovskoye, Kulbeshkakskoye, Ust-Labinskoye fields, their amount is 46-63%.

Stable condensate from the same field can have different characteristics. This depends, on the one hand, on the decrease in the reservoir pressure of the field, on the other hand, on the operating mode of the installations where heavy hydrocarbons are separated from gas. Thus, a decrease in the isotherm at LTS units increases the degree of condensation of hydrocarbons gs, C 6, which in turn leads to an increase in the content of light fractions in the condensate. The influence of separation temperature on the fractional composition of condensate is especially significant when its content in the reservoir gas is insignificant and the content of high-boiling fractions is high.

The physicochemical characteristics of condensates determine their commercial properties.

To assess the possibility of obtaining certain brands of motor fuels from condensates, their unified technological classification was established according to the industry standard OST 51.56-79. According to this classification, condensates are analyzed according to the following indicators: saturated vapor pressure, sulfur content, fractional composition, content of aromatic hydrocarbons and paraffins, pour point.

I - sulfur-free and low-sulfur with mass fraction total sulfur no more than 0.05%. These condensates do not require purification from sulfur compounds;

II - sulfurous with a total sulfur content from 0.05 to 0.8%. The need to purify condensates of this class and its distillate fractions in each specific case is decided depending on the initial requirements;

III - high-sulfur with a total sulfur content above 0.80%. The inclusion of a unit for removing sulfur compounds in the processing schemes for these condensates is mandatory.

Based on the mass fraction of aromatic hydrocarbons in gas condensates, they are divided into three types: A 1, A 2 and A 3 . Types A 1, A 2 and A 3 include condensates containing more than 20, 15-20 and less than 15% aromatic hydrocarbons, respectively.

H 1 - highly paraffinic, in the fraction of which with a boiling point of 200-320°C the content of complexing agents is at least 25% (wt.). From these condensates, liquids, n-alkanes and jet and diesel fuels can be obtained using a dewaxing process;

H 2 - paraffinic, the 200-320°C fraction contains 18-25% (wt.) complexing agents;

H 3 - low-paraffin, the content of complexing agents in the 200-320 °C fraction is 12-18% (wt);

H 4 - wax-free, the content of complexing agents in the diesel fraction is less than 12% (wt.).

According to the fractional composition, condensates are divided into three groups - F 1 F 2 and F 3:

F 1 - condensates of a lightweight fractional composition containing gasoline fractions of at least 80% (wt.), boiling no higher than 250 ° C;

F 2 - condensates of intermediate fractional composition, boiling away within the temperature range of 250-320 ° C;

F 3 - condensates boiling above 320°C.

Thus, a technological characteristic code is established for gas condensate, which is used to determine the appropriate direction for its processing. For example, the condensate of the Shatlyk field is designated by the code IA 3 N 1 F 3. The characters included in it are decrypted as follows:

I - class: the total sulfur content in the condensate is no more than 0.05% (mass.); A 3 - type of condensate: content of aromatic hydrocarbons less than 15% (wt); H 1 - type: highly paraffinic condensate, in the 200-320 ° C fraction the content of complexing agents is above 25% (wt); F 3 - end boiling point above 320 °C.

Where ,gi- mass content of sulfur compounds in stable condensate, %; M i -molar mass sulfur compounds; T- the number of sulfur atoms in the substance.

Gas condensate is a mixture of liquid hydrocarbons condensed from natural gases. Gas condensate is a colorless or slightly colored liquid. Externally, as a rule, gas condensate is a transparent liquid. The color of this liquid can vary from straw yellow to yellow-brown. What does the color of a substance depend on?

It turns out that the intensity of the color of a liquid depends on the amount of oil impurities it contains. You may have heard the name “white oil”. So, this is the generally accepted name for gas condensate.

How is gas condensate separated? Deep in the depths of our earth lie various minerals. Including gas and gas condensate. Having discovered these deposits, the mining company drills a well into the thickness of the earth, trying to get to gas-containing layers. During drilling, the pressure in the formations decreases and at the same time the temperature decreases. As you know, any condensation appears when either the temperature drops significantly environment, or pressure. This is exactly the process that occurs in gas production. The pressure and temperature drop, and at the same time liquid hydrocarbons of mixed composition (C5 and higher) begin to be released from the gas. This is our “white oil”.

Moreover, the higher the barothermal indicators before condensation begins, the greater the amount of hydrocarbons that can be dissolved in the produced gas. The amount of hydrocarbons is also affected by the composition of the gas in the reservoir and the presence of “oil rims”. An oil rim is a part of a reservoir containing oil, as well as gas and condensate. Gas condensate can concentrate in the formation within varying limits - from 5 g/m? up to 1000 g/m?. If gas deposits are located at great depths, then to obtain condensate it is necessary not only to lower the temperature of the gas, but also to additionally absorb and rectify it.

In order for the pressure in the formation to remain at a high level for as long as possible, hydrocarbons of the C1-C2 fraction are pumped back into the well. As a result, so-called “unstable” condensate is obtained directly from the well. It reaches consumers via special conductive systems. Unstable condensate is thoroughly cleaned from impurities and gas is removed from the composition. Now it becomes "stable". This type gas condensate reaches the end consumer either through pipelines or liquid transport.

What is the composition of gas condensate? The composition of gas condensate is influenced by many factors. The hydrocarbon composition of the condensate and the number of fractions in it are influenced by the formation conditions; conditions under which the selection of a substance occurs. It is very important to take into account the period of time during which a given deposit is exploited. Earlier we mentioned the influence of the “oil rims” present in the reservoir on the composition of the condensate. The conditions for migration of gas condensate into deposits during its formation should also be taken into account, as well as chemical composition reservoir gas. In general, the contents of gas condensate are similar to oil. But, unlike oil, gas condensate does not contain resinous substances and asphaltenes. Basically, it includes gasoline and kerosene components.

Gasoline fractions boil at a temperature of +30 °C - +200 °C, kerosene fractions - within +200 °C - +300 °C. Included in condensate and not a large number of high boiling components. The yield of gasoline fractions is usually more than half. If the formation is located at great depth, then its composition is dominated by kerosene components and gas oil. More often there are condensates containing methane and naphthenes, less often - containing aromatic or naphthenic hydrocarbons.

What is gas condensate used for? Gas condensate serves as the basis for obtaining fuel or petrochemical products. So from gas condensate or high quality gasoline. To improve quality, gasoline fractions obtained from condensate are subjected to additional processing. In order to increase the fuel's resistance to detonation, anti-knock agents are added to the composition. Without additional processing, these types of fuel can only be used in the warm season, as they quickly become cloudy and solidify. In order for these types of fuel to work even in cold weather, paraffin is removed from their composition.

For the production of plastics, synthetic rubbers, various types of fibers and resins, aromatic hydrocarbons, olefins and other monomer molecules obtained by processing gas condensate are used. Mining companies are interested in developing condensates available in large fields. They commission installations with a large unit capacity.

For example, the Gazprom company owns fields with gas condensate reserves amounting to more than 1 billion tons. In year this company produces about 13 million tons of gas condensate.
Liquid mixtures of hydrocarbons (all of them differ in different molecular structures and boil at high temperatures), which are released as a by-product in gas condensate, gas and oil fields, are collectively called gas condensates. Their composition and quantity depend on the location and conditions of extraction, and therefore vary widely. However, they can be divided into two types: stable gas condensate in the form of gasoline-kerosene fractions (and sometimes higher molecular weight liquid components of oil), an unstable product, which, in addition to hydrocarbons C5 and higher, includes gaseous hydrocarbons in the form of methane-butane fraction .

Condensate can come from three types of wells where it is produced: Crude oil (it comes in the form of associated gas, which can lie underground separately from crude oil (in layers) or be dissolved in it). Dry natural gas (features a low content of hydrocarbons dissolved in it, condensate yield is low). Wet natural gas (produced from gas condensate fields and has a high content of gasoline condensate). The amount of liquid components in natural gases varies from 0.000010 to 0.000700 m? by 1 m? gas For example, the yield of stable gas condensate at various fields: Vuktylskoye (Komi Republic) - 352.7 g/m?; Urengoyskoe (Western Siberia) - 264 g/m?; Gazlinskoe (Central Asia) - 17 g/m?; Shebelinskoe (Ukraine) - 12 g/m?.

Natural gas condensate is a multicomponent mixture of various liquid hydrocarbons with low density, in which gaseous components are present. It condenses from the raw gas during the temperature drop during well drilling (below the dew point of the produced hydrocarbons). It is often called simply "condensate" or "gas gasoline". Schemes for separating condensate from natural gas or oil are varied and depend on the field and purpose of the products. As a rule, on technological installation, built next to a gas or gas condensate field, the extracted gas is prepared for transportation: water is separated, purified to a certain extent from sulfur compounds, hydrocarbons C1 and C2 are transported to the consumer, a small fraction of them (of the extracted) is pumped into the formations to maintain pressure. The separated fraction (after removing C3 components from it, but with a small content of them) is the gas condensate that is sent as a feed stream to oil refineries or petrochemical synthesis plants. Transportation is carried out by pipeline or liquid transport.

Gas condensate at oil refineries is used as a raw material for the production of gasoline with a low octane number, to increase which anti-knock additives are used. In addition, the product is characterized by a high cloud point and pour point, which is why it is used to produce summer fuel. Gas condensate is used less frequently as diesel fuel, since additional dewaxing is required. This direction uses less than a third of the produced condensates.

Most interesting technological solution is the use of a product such as a wide fraction of light hydrocarbons for petrochemical synthesis. With its receipt, the processing of gas condensate begins. Deeper processes continue in pyrolysis plants, where NGLs are used as feedstock to produce important monomers such as ethylene, propylene and many other related products. Then the ethylene is sent to polymerization units, from which various grades of polyethylene are produced. As a result of the polymerization of propylene, polypropylene is obtained. The butylene-butadiene fraction is used to make rubber. Hydrocarbons C6 and higher are the raw material for the production of petrochemical synthesis (benzene is obtained), and only the C5 fraction, which is the raw material for obtaining valuable products, is not yet used effectively.

Gas condensate distillate is an analogue of diesel fuel, close to it in density and other characteristics. It contains gasoline and kerosene fractions, but asphaltenes and resinous substances are absent. Gas condensate distillate is a transparent liquid with a specific odor. It can be light, medium and heavy, differing in composition and scope of application.

We can say that gas condensate distillate, the price of which is relatively low, can be an excellent alternative to diesel fuel. And also, thanks to its decent quality, this product has gained immense popularity in the petrochemical and paint industries. 01/31/18

Any condensate is obtained after the transition of a gaseous substance into a liquid due to a decrease in pressure or temperature. In the bowels of the earth there are not only gas, but also gas condensate deposits. When pressure and temperature are reduced as a result of drilling a well, gas condensate is formed - a mixture of liquid hydrocarbons that have separated from the gas.

Under condensation understand the content of liquid hydrocarbons in gas under reservoir conditions (cm 3 /m 3).

Gas condensate factor is the reciprocal of condensation.

Distinguish raw And stable condensates. By raw we mean hydrocarbons that, under standard conditions, are in a liquid state with gaseous components dissolved in them (methane, ethane, propane, butanes). Condensate consisting only of liquid hydrocarbons (from pentanes and above) under standard conditions is usually called stable.

By physical properties condensates are characterized by great diversity. Density condensates varies from 0.677 to 0.827 g/cm 3 ; refractive index from 1.39 to 1.46; molecular mass - from 92 to 158.

Compound. Numerous studies have established the genetic connection of the underlying (formed) oils. Condensates, like oil, consist of three types of hydrocarbons - methane, naphthenic and aromatic.

However, the distribution of these hydrocarbon groups in condensates have the following peculiarities unlike oils:

1) the absolute content (on average) of aromatic hydrocarbons in gasoline fractions of condensates is higher than in oils;

2) there are gasoline fractions that simultaneously contain a large amount of naphthenic and aromatic hydrocarbons;

4) concentrations of branched methane hydrocarbons are lower than the concentration of normal structures;

5) the share of ethylbenzene among aromatic hydrocarbons of composition C 8 H 10 is on average. significantly lower % than in oils.

Thus, condensates consist of simpler compounds than oil. Cyclopentane hydrocarbons predominate in oils, and cyclohexane hydrocarbons predominate in condensates. Aromatic hydrocarbons in oils are usually concentrated in high-boiling fractions; in condensates, on the contrary, in low-boiling ones. The sulfur content in condensates ranges from 0-1.2%. In individual deposits or wells, condensates may be found, the hydrocarbon composition of which may deviate from general patterns, this is due to the geological features of a particular area.

The condensates are noticeably different and by fractional composition. On average, they boil 60-80% to 200C, but there are condensates (or oil-condensate mixtures) whose end boiling point is 350-500C, containing asphaltenes.

During the development of gas condensate deposits, the composition of condensates changes. As the pressure decreases, partial condensation of hydrocarbons in the formation occurs, and this part is basically no longer extracted to the surface. As a result, there is a change in the quantitative and qualitative characteristics of the reservoir gas-condensate mixture - a change in the group hydrocarbon composition. As the pressure decreases, high-boiling condensate fractions fall into the formation, and its density decreases. Sometimes the density of condensates, on the contrary, increases, which is mainly characteristic of developed gas caps.

Thorio writes:

TaxHelp writes:

I'm bringing up an old topic. The Supreme Arbitration Court is now deciding whether one of TNK's subsidiaries produced oil or condensate (this affects taxes). Of course, no one in court will bother with the analysis of c7. The decision will be made in a month and a half at best. If you have a Facebook account, you can watch the video recording of the court hearing.

The biggest problem of TNCs, IMHO, is Accounting: They spent everything under oil.

But the position of the tax inspectorate is striking. In a nutshell, they mixed the extracted oil and condensate and sent the mixture to a product preparation facility. The question for the inspection is whether gas condensate was prepared at product preparation facilities? The answer is “no”.

The tax authorities are having a blast! I just collapsed with laughter listening to the taxman’s speech. To the question “Did gas condensate arrive at the treatment reception points?” he replied “Only HYDROCARBON RAW MATERIALS arrived at the reception points, but gas condensate was not allowed in!”.... (Thorio, this struck me too)))

Such illiteracy, stupidity and stupidity just turn out the lights.

The taxman’s “important” argument is that the output products were assessed according to GOST for commercial oil, which means that only oil was produced, but there was no condensate! "There was no boy, there was no!!" “It doesn’t matter that there are gas deposits on the balance sheet and condensate is being extracted from them! Hydrocarbon raw materials came in, and the output was OIL, which means you pay grandma, capitalist-exploiter!!”

Insanity is for the insane. Yes, there is nothing but oil, and there shouldn’t be. Both condensate and oil are a single substance, varying in properties. And that is why there is no GOST for condensate, but there is a GOST for COMMERCIAL oil.

The state is again stepping on its rake, which, unfortunately, knocks not only on the heads of government agencies, showing all their incompetence, but also on the heads of subsoil users.

Is it really so difficult to rewrite several laws, and if it is so important to keep records of production (and this is really important because it affects the wear and tear of equipment, etc.), then keep records not according to the type of phase state of the formation fluid in the formation (the railway worker doesn’t give a damn "what does the subsoil user have in the reservoir - liquid oil or reservoir gas from which condensate falls out), and according to the characteristics commercial products after preparation and before shipment by rail or Transneft pipe - density, content of sulfur-containing substances, paraffins, fractional distillation, etc. - these are the characteristics that are important for the transporter, and are prescribed in GOST for commercial oil!

Please, then, any tax officer come with your certified thermometer and measure the density and check. Check the laboratories that issued the analysis document.

The only trouble is that it won’t be interesting anymore. Fish bite better in muddy water! You look at it in court and it’ll “ride” - the judges are not geologists, it’s difficult for them to figure out what is condensate and what is “unstable condensate”, they can also believe that butane, as a separate component of a multi-component system, can be separately developed from a deposit (!) (laughing to no magician). And the proceeds to the budget from an “unscrupulous” entrepreneur is a bonus!

The state has made a mess in this matter, and the tax authority, as a representative of this state, says “I will punish you in full for this mess.”

Free circus!

It's all sad. What a charade...this is the state....

P.S. Looks like I know which region the legs grow from. The smartest tax office is there

It’s also a pity that the subsoil user does not always, in my opinion, clearly outline the situation. Although I’m not a lawyer, I think I can explain to a lawyer the difference between condensate and oil. I already have experience))

It would be a good tradition to invite not only lawyers but also high-level specialists and experts to the court. And let them speak from the side of the court, explaining to the judges the essence of the issue. Then it will be more difficult for some authorities to explain themselves in court.

Also, it should be very profitable for subsoil user companies to take the initiative to change legislation in matters where there is a mess. There is no one else to do this. It will cost less than constant tax collection. Rosneft definitely won’t do this, the penalty for them is transferring money from one pocket to another. The institutions don’t give a damn about such problems, and even those who still survived are in ruins. This remains only for private companies.

Converter