The way the thermo-chemical dewaxing of pipelines in the flow of transported oil on them
(57) Abstract:The invention relates to the field of extraction and transportation of oil. Described thermo-chemical dewaxing process piping in the flow of transported oil on them using astheneia system in which the processing liquid is used as the liquid for dewaxing, consists of (a) solution of nitrogen-containing salts, activated emulsified acetic acid and leading to the nitrogen and heat, and b) a solvent which is produced by oil. The technical result of the invention is that deparaffinizing processing is performed simultaneously with the receipt of oil, which leads to large cost savings and energy. 15 C.p. f-crystals, 1 Il., 5 table. . The invention relates to a method of thermo-chemical dewaxing of pipelines is carried out in the flow of transported oil on them. In particular, the present invention relates to carried out in the pipeline method of thermo-chemical dewaxing of large pipelines transporting oil, which have no or deprived of any alternatives to the removal of the produced oil during dewaxing. This way dewaxing PR is storytale, which may be an oil, produced or transported. Oil production is not interrupted during dewaxing.Depending on the physico-chemical characteristics of oil, which is transported through underwater pipelines, in it there is a widely known phenomenon of the formation of paraffin sediments, which leads to losses and increase value. The phenomenon of deposition of paraffin, essentially, means the gradual and progressive separation of paraffin from organic compounds along the pipeline. The so-obtained oil having a paraffin content higher than 3 wt.%, show high potential deposition of paraffin, when they are examined in terms of fluidity, the relevant characteristics of the submarine system pumping.The process deposits are closely associated with low temperatures at the bottom of the sea, the temperature gradient between the oil and sea water during underwater pipe, with flow rates of oil and gas, with the resulting dispersion, and, to a lesser extent, the process associated with gravity segregation and Brownian motion. The formation of paraffin crystals associated with WAT (Wax Appearance Temperature - the temperature of the appearance of the paraffin (CCI), defined as the highest temperature at Coty controlled cooling in Isobaric conditions..."
U.S. patent 4755230 discloses the use of reaction heat and the formation of nitrogen for dewaxing of pipelines transporting hydrocarbons, using an emulsion of oil - in - water and hydrochloric acid as activator specified reaction with generation of heat and nitrogen. Further, the method requires the introduction of an organic solvent as a crystal modifier in order to preserve as at a lower level point cloud paraffins and, thus, to avoid their precipitation in the pipeline after cooling. This method requires that the wax part of the pipeline was isolated from the rest of the pipeline. The path that perform the method may lead to a situation where the deposition of paraffin simply shifted inside a pipeline, without being subjected to destruction. In addition, the direction of pumping of the treatment solution may cause the tube at one end of the pipeline, and thus to cause damage due to high blood pressure.Description to GB-B-2276218, and this description fully disclose the method of dewaxing in respect of pipelines having a diameter up to 4 inches (1 inch = 2.54 cm) and Dora delayed action. Solutions of nitrogen - and fuel or generating salts are prepared on the ships, the solution of each salt is prepared in a separate vessel.The description of the patent application U.S. serial number 08/742126 dated 31 October 1996, the Applicant and the description fully disclose the method of dewaxing pipe up to 50,000 meters in length and internal diameter up to 12 inches, using astheneia system, in which the delayed action activator reactions that produce nitrogen and heat, is polyadipates anhydride managed hidromassagem. In the method described in US 08/742126, solutions of nitrogen-containing salts get in a single vessel on the mining platform. Salt-containing solutions stabilized by adding NaOH and emuleret using an organic solvent. The delayed action activator is added to the flow of emulsion nitrogen-containing salts. As the organic solvent used, for example, kerosene. The requirement for the method is or destruction of or any other moving total amount of oil contained in the pipeline. Then, the processing fluid is injected into the pipeline or from the rig or platform, either through time, which is required for the development of chemical reaction between the nitrogen-containing salts and liquefaction of sediments. Then waste fluid and emulsified paraffin extract and resume operation of the wells.Thus, known from the literature methods either require expensive ship maintenance, such as described in GB-B-2276218 or interrupting the process of oil extraction, as described in US N 08/742126, resulting in large economic losses in the process. Further, these methods can not be applied to pipelines for transportation of oil, of which it is impossible to remove the oil during the dewaxing process.Therefore, in the field of dewaxing pipelines there is a need for a thermochemical method, using azathioprinum system for dewaxing pipes of large dimensions, in which the solution of the nitrogen - and fuel salts are mixed with the produced oil. This avoids interruption of oil production, as well as use as solvents expensive oil fractions, which leads to great savings. This method is described and claimed in the present invention.Generally speaking, the present izobreteniya, transporting hydrocarbons carried out directly in the pipeline, the flow of oil, using astheneia system, where thermochemical effect is provided of the processing liquid which is in contact with the paraffin deposits and oil used as a solvent, and nitrogen and heat, which chemically are generated from a nitrogen-containing reagents.Thermochemical method, implemented directly in the pipeline for dewaxing oil transporting pipelines using astheneia system includes the following stages:
a) defining a chamber (temperature appears paraffin) for samples extracted oil, the identification of the phenomenon of formation of paraffin sediments as well as its localization in pipelines transporting oil;
b) determining the optimum amount of oil that should be used as a solvent available mass of paraffin in pipelines transporting oil, in order to carry out the dewaxing;
C) preparation of heat and attenersi salt solutions and pilot test dewaxing;
d) preparation of an aqueous solution of activator delayed action is the dominant oil, the processing liquid received from the heat and attenersi solutions of salts, oil, and slow activator actions taken in the quantities specified in (C) thus, in order to carry out the dewaxing of pipelines transporting oil, simultaneously with its production;
f) after injection fee of terminal waste liquid obtained after the processing of paraffin oil and aqueous waste solution in a liquid form.In accordance with the present invention, which relates to a method of thermo-chemical dewaxing of larger pipelines transporting oil, using azathioprinum system, the solution of the nitrogen - and fuel salt is mixed with the produced oil, without halting the process of its production. Thus, this method is combined with the production of the dewaxing in the pipeline, allowing the Applicant to call this process "astheneia system/stream'. Activation of the reaction between the nitrogen-containing salts is carried out by adding acetic acid or pre-emulsified acetic acid.Thus, the present invention provides Edinoverie Ryuusei system, where the solvent of paraffin deposits inside the pipes is produced or transported oil.The present invention also provides simultaneously flowing the way thermo-chemical dewaxing of larger pipelines for transportation of oil, which is carried out without interrupting the process of oil production, and which does not require the addition of expensive oil fractions as solvents paraffin.The drawing shows a phase diagram of a mixture of solvent/ wax in the case where the solvent of paraffin is either aviation kerosene, as described in the literature or oil mixture used in accordance with the present invention. We choose the oil mixture, because the oil used in accordance with the present invention as a solvent of paraffin, is a composition or physical mixture of oils from various wells, for example three or more. The drawing shows that as the point of mixing the mixture of oil-paraffin slightly lower than in the case of using kerosene as a solvent, this leads to somewhat lower efficiency oil mixture as solvent paraffin, but the usage is Isani and in the claims of the present invention is disclosed, the liquid dewaxing or the processing liquid is a liquid obtained from a solution of nitrogen-containing salts, which generate nitrogen and heat, namely salts such as sodium nitrite and ammonium chloride, or sodium sulfate and ammonium chloride, the reaction of the nitrogen and heat is inhibited using the delayed action activator, such as acetic acid.Thermochemical method, implemented using astheneia system in accordance with the present invention, combines the results from the action of dissolving, mixing and heating that can effectively dissolve paraffin deposits in pipelines transporting oil. As indicated above, the present method is particularly directed to the processing of such pipelines transporting oil, which cannot be unloaded petroleum products during processing.The present invention is directed to a dewaxing larger surface, underground or underwater pipelines transporting oil, which carry oil or its fractions often at reduced temperature, for example at a temperature below 10oC.Selection Astia.The solvent used in the manufacturing of the liquid is oil, which is produced or transported.As was shown above, the nitrogen and heat occurs due to the reaction between nitrite ions and ammonium ions, which are present in aqueous solutions of these salts.Nitrogen - and heat-generating aqueous solutions containing (a) a compound containing at least one nitrogen atom is attached at least one hydrogen atom, while this compound is capable of rapid and exothermic oxidation in acidic aqueous solution with evolution of heat, nitrogen and by-products, which are liquid or soluble and essentially inert with respect to the pipeline; (b) at least one oxidizing agent, which is able to oxidize the nitrogen-containing compound according to paragraph a); (C) a buffer system, which is capable of maintaining the pH of the solution at the level of about 7,0-7,5.Among pairs of compounds a) and b) in the present process using ammonium chloride and sodium nitrite or ammonium sulfate and sodium nitrite, which are essentially adequate. In a preferred embodiment, an organic solvent, which in accordance with the present izobreteniya denoted as 'C'+N" solution; an aqueous solution of ammonium sulfate and sodium nitrite is designated as "S+N" solution. An aqueous solution of nitrogen-containing salts are used in molar concentrations up to 4.5 mol of each of the salts.The idea of processing pipelines transporting oil, in accordance with the present invention is based on the irreversible liquefaction deposits of paraffin, liquefaction, which is obtained from the simultaneous effect of increasing the temperature of the liquid, the internal turbulence of the flow, as well as by adding deposition of paraffin oil, working in the process as the solvent.Used in this process, the expression "stream line" or "production line" means a pipeline, which delivers oil from the wells to the platform, while the expression "the pipeline transporting oil" means a pipeline that transports oil, which was extracted, processed and separated in the separator on the platform and then sent to the terminal or tanker.Typically, the diameter of pipelines transporting oil, greater than the diameter pipelines feed line, for example, 8 inches for transporting pipelines against 4 inches for producing pipelines.
Oh a mixture of oils from various wells, for example, three wells. The mixture is separated from the gas and the water formed in the separator on the platform and transported through a pipeline to transport oil.In addition, in the present description, the expression "solution of nitrogen-containing salts, emulsified in the produced oil, doesn't mean adding an emulsifier to a solution of nitrogen-containing salts. In fact, it refers to the turbulence created by the nitrogen, which is easily emuleret solution of the nitrogen - and heat-generating salts in crude oil (unstable emulsion).The processing liquid used in the present thermochemical method includes, essentially, a solution of nitrogen-containing salts are ammonium chloride and sodium nitrite or ammonium sulfate and sodium nitrite, emulsified in the flow of produced oil, while the oil is heated to the exit temperature of the separator oil - gas platform. As mentioned in GB-B-2276218 and request US 08/742126 and as disclosed in the present description the solutions of nitrogen-containing salts, emulsified in the flow of produced oil, prepared in concentrations that optimizes the process of obtaining nitrogen and heat required to conduct the dewaxing. Typically, the solution contains DoD. To the solution was in stable condition, maintain its pH is between 7.0 and 7.5 by adding NaOH solution.Further, this method uses the idea of delayed action activator, based on the fact that nitrogen-containing salts do not react with each other to form the desired amount of nitrogen and heat, as it requires the activator. However, it should be noted that such activation should not be immediate and instant, because there is a need in the down periods of interaction between the salts corresponding to the period of injection of the desired amount of the processing liquid. According to the desired period of deceleration, the delayed action activator can be concentrated acetic acid (100%) and concentrated acetic acid, pre-emulsified, for example, emulsion water-in-oil prepared from acetic acid, water and aliphatic hydrocarbons such as pentane, hexane or petroleum fraction such as diesel fuel and the emulsifier or surface-active agent.The delayed action activator for the reaction under nitrogen and heat can be selected from those described in the application US. Suitable acetic acid may be used, as described in GB-B-2276218. Can also be used emulsified acid as described in US 5183581.In one of the embodiments of the present invention, the reaction can be activated by using concentrated acetic acid is used in an amount of from 0,15 to 0,50% of the total volume of the processing liquid.In another embodiment of the present invention can be used emulsion water-in-oil prepared from acetic acid/water/aliphatic hydrocarbon, taken in amounts of 0.75 to 1.25% from the total amount of the processing liquid.According to this embodiment of the invention the activator for the reaction of nitrogen-containing salts is a concentrated solution of acetic acid (100%) in water in the presence of aliphatic hydrocarbon which forms an emulsion of water-in-oil in the presence of surface-active agent. Aliphatic hydrocarbon is a linear aliphatic hydrocarbon, C5- C7such as pentane, hexane or heptane or petroleum fractions, such as diesel fuel. The active substance of the activator is acetic acid. Dispersion or the aqueous phase of the emulsion obtained from the water and the second fuel. The relative amount of the dispersed and dispersing phases can vary within wide limits, providing the necessary stability of the dispersing phase, which should remain unchanged. Thus, the lower limit for the quantity of the dispersing phase is 25 parts by volume, the remaining 75 parts by volume be 37.5 parts of water and 37.5 parts of concentrated acetic acid. In the upper limit of the dispersing phase will contain 75 parts by volume, while the dispersed phase will contain 12.5 parts of water and 12.5 parts of concentrated acetic acid. The preferred volumetric amount of activator to be used is 20 parts water 20 parts of acetic acid/60 parts of diesel fuel plus surface-active agent.The amount of emulsion and activator should be used is a function of the number of active agents, such as acetic acid, mixed with an emulsion. For example, if the emulsion activator contains a smaller amount of acetic acid, it should require a little more volume number in order to activate. So, this emulsion, which has a content of 20 parts of water/20 parts of acetic acid is the fact that liquid, corresponds to 0.2% of the active substance emulsion and slows down the reaction between the nitrogen-containing salts at 18 min (see table 4 below).If the active substance is present in smaller quantities in the emulsion activator, higher volumetric quantity of the activator must be added to the processing liquid in order to extend the deceleration time, due to increased stability of the emulsion (see experience n04 in the table 4 below).Lipophilic surface-active agent provides the desired emulsion water-in-oil aqueous acetic acid in the hydrocarbon.Among the lipophilic surface-active agents which are suitable for the present invention are agents based on fatty acids, such as sorbitol esters, which can be used and are widely distributed.Surface-active agents are used as emulsifiers emulsions activators in slow motion, are present in a volume amount which is between 0.5 and 1.5% in the calculation of the volumetric amount of the emulsion activator.The amount of the processing liquid, which should be used is usually determined on the basis of data Parvata simulation determines the temperature dependence of the flow of oil in the pipe. From the temperature dependence is possible to estimate the degree of formation of paraffin sediments.The following mathematical modelling is associated with thermodynamic behavior of fluids during deparaffinizing processing.The first step during the research that led to this method was the determination of thermal and kineticheskogo behavior of a saturated solution of reagents, which are azathioprinum system, such as ammonium chloride and sodium nitrite (solution C+N), in the presence of oil, previously heated to a temperature close to the temperature at the outlet of the separator mixture of gas oil on the platform. In the embodiment of the invention, which leads to a more prolonged slowdown for the reaction between the nitrogen-containing salts, delayed action activator, which should be used is acetic acid, emulsified in water/ diesel fuel in the presence of a lipophilic surface-active agent.It was found that the ammonium sulfate can be advantageously used instead of ammonium chloride without any of the kinetics, while the sulfate salt has a lower price and widely distributed.In General, this is no such successive stages:
The first sampling of the produced oil and the definition of CCI (temperature appears paraffin) using a DSC (differential scanning calorimetry), and then conducting mathematical modeling to identify the phenomenon of formation of paraffin sediments and its localization in the pipeline;
II determine the effectiveness of the produced oil as a solvent of paraffin to determine the optimum ratio of oil to the wax, which is necessary for the liquefaction of paraffin;
III using mathematical modeling conducting deparaffinizing processing based on thermodynamic behavior of fluids during the formation of paraffin sediments;
IV determination of reaction kinetics in the laboratory on the platform, on the basis of solutions of heat and attenersi salts;
V injection from the platform: a) manufacturing a liquid prepared from a solution of nitrogen-containing salts, C + N or S+N; (b) the oil separator and (C) delayed action activator in accordance with a predefined number;
VI transfer of enriched paraffin oil and waste liquids in the terminal or tanker. The remaining nitrogen is vented into the atmosphere, while water from aqueous solutions of salts discharged.
assets, the present invention requires that the CCI was determined, as it is a temperature below which appear the deposition of paraffin. CCI oil from different wells, as well as their mixtures, which must be transported to the terminal after separation from the gas in the separator on the platform determine, based on data in kinematic viscosity. Table 1 below includes the data.When considering the tendency to the formation of paraffin, which is manifested in different wells, it was found that, as a pipeline to transport oil from the well 1 to the platform is not very long, in it, despite the low value of the CCI, the formation of paraffin sediments was not. However, for pipelines that transport oil from wells 2 and 3 were observed to have a strong tendency to the formation of paraffin sediments curved pipe, starting from the second mile. Underwater flow scheme of these wells allow the oil to cool below the corresponding value of the CCI. After treatment of the oil in the primary separator, the value of the CCI increases slightly (15.1oC) to the resulting mixture, which when pumping through a pipeline with a diameter of 8 inches and a length of 21 km to monoboy, shows a gradual loss of load and posledovatelno developed design capacity or 20% of its loss.In some cases there is a decrease in the efficiency of heating in the separator when the temperature of the oil output falls from 75oC to 55oC. as a Result, the oil becomes more viscous and bandwidth still falling, for example, up to 1700 cubic meters per day, which represents 70% of the initial daily production. So the temperature corresponding to the CCI, can be predicted as a consequence of lowering the temperature coming out of the oil and the speed of its flow. Thus, increasing the formation of paraffin sediments of the pipeline should be expected, mainly in the sections located close to the platform.The study of the chemical characteristics of oils each of the wells 1, 2 and 3 showed a wax content between 3 and 5 wt.% and asphaltenes between 0.6 and 2.1 wt.%, that means a high possibility of organic deposits in that case, if the oil in the pumping sub-sea pipelines.Table 2 below shows the results of physico-chemical study of the properties of oils wells 1, 2 and 3.In addition, it was necessary to determine whether to use composition or the physical mixture of oils, paraffin as a solvent when pumping on the fluidity of the mixture of paraffin oil is reduced in the same way, as in the case when for dissolving paraffin use kerosene, such as aviation kerosene. As can be seen from table 3, it was found that in normal sea temperatures in deep-sea equipment the mixture of oils can contain paraffin (C21H44standard), in the conditions created by the flow, at least in the ratio of three parts of oil per part of wax.This means that oil, for example, a mixture of oils of different producing wells in one field, can be easily used as an organic solvent in a thermochemical method according to the present invention. Another advantage is that the oil leaves the separator at a temperature of around 75oC, which provides additional thermal energy for use in the process.Table 4 below presents the data of the kinetics of a chemical reaction system, nitrogen generation, dispersed in a mixture of oil, used as a solvent of paraffin according to the invention. It was found that increasing the amount of C+N solution of from 10 to 30% by volume leads to an increase of the maximum temperature from 79oC to 100oC, which provides the state of the mixture, blio 20% by volume of C + N solution of mixtures of oils allows you to reach a temperature not higher than 91oC for a reaction time of 13 minutes and the yield of the reaction is about 90%, which is very well suited for work in the field.Alternative prepare the emulsion of acetic acid in diesel fuel, stable lipophilic surface-active agent and is used as an effective activator of delayed action. This emulsion provides a slightly greater delay (compared with activation acetic acid) early reactions generate heat and nitrogen, which is useful to meet the requirements of the flow velocity and pressure in the pipeline. For example, at a concentration of 0.75% by volume of the emulsion acid provides a delay of 18 minutes to start the reaction, while 1% of the volume. the delay was equal to 18 min and the yield of the reaction was 88% by volume. Thus, the use of acetic acid as activator in slow motion, diluted, or in the form of an emulsion, satisfies the requirements of the present invention.The kinetic data in table 4 also show that the properties of ammonium sulfate in this way, very close to the properties of ammonium chloride, so that it can be used in place of ammonium chloride. Ammonium sulfate is loansportal oil.Thus, based on the preliminary determination of the values of the CCI, the chemical characteristics of the transported oil, the phase diagram of mixtures of oil/paraffin and kinetic data for the chemical reaction between the salts, generating heat and nitrogen, each a specialist in this area can develop deparaffinizing way for oil transporting pipelines.Performance data and schema underwater communications field study were summarized in table 5 below, as the next step in the development of a method for dewaxing mentioned previously pipelines to transport oil. It was found that a significant reduction in performance of the studied deposits are closely associated with the deposition of paraffin in a discharge tube wells 2 and 3, and mainly in the pipeline to transport oil. It was also noted that the phenomenon of deposition of paraffin may be associated with undesirable decrease in the temperature of the oil leaving the separator.The assumption of heating oil in the pipeline is considered as the ability to prevent paraffin deposits in the pipe. However, due to the large length of the pipe - 21000 m - variant ocas is selected temperatures indicates the start of the deposition of paraffins. When implementing heating its only effect is to change the location of the initial localization of the deposits of paraffin on monomoy.Pre-heat balance of the site pumping oil from the platform to monoboy leads to the establishment of the heat loss oil weight equivalent to one of the nominal volume of the pipeline, comprising about h6kilocalories.Based on the calculations of thermal weight loss of oil in the pipeline and adding minimal additional heat to ensure the transition is already available inside a pipeline paraffin deposits in liquid state was defined as a hypothetical amount of the processing liquid according to the process SGN/ON - LINE. This volume was about 136 m3saturated C+N solution, which is able to allocate about 40 x 106kilocalories. The heat will increase the temperature in the pipeline to about 93oC, which, together with the solvent action of the oil and mechanical thinning effect of nitrogen, are sufficient to translate into irreversible liquefied state of paraffin deposits.Heat balance of oil transportation and processing pipeline to transport oil )/kgoC (75-14oC)= heat Loss = 24036000 Kcal.In the Heat formed during the processing pipeline
Heat = 136 m3*of 4.5 mol/l 75 Kcal/l 0.88 mol/mol = the accumulated heat = 40392000 Kcal.C) Average temperature during processing**< / BR>40932000 - 24036000 = 680 O 80 0.878 0.66 (Tequally- 75) + 6800,201,101,0(Tequally- 25) = 93oC
*Considering the characteristics of the processing pipeline according to the process SGN/ON - LINE was set amount of C+N solution (136 m3). This volume was taken as the respective working volume mounted tanks, as well as the necessary heat for processing the pipe sections.**To simplify calculations, the average temperature of the processing liquid, as well as operational security, it was conservatively assumed that the heat loss during the treatment process SGN/ON - LINE will be approximately equal to the losses observed during the transportation of crude oil. Further calculations will be carried out in order to calculate the actual temperature in the section subjected deparaffinizing processing.According to a preferred embodiment of the present invention effective deparaffinizing the RA salts C+N or S+N in the flow of oil, after a preliminary reduction of the flow velocity of the oil. This reduction of flow must be of the same order as the input stream SGN. The pumping C+N solution can be carried out using a triple pump with positive displacement, flow rate is 1.75 barrel per minute (bpm). The amount of activator in the form of an emulsion of acid is added to the stream, preferably in a mixture of oil/C+N solution using a metering pump, operating in the range of 0.5 to 1.5 gallons per minute. According to this embodiment of the method the entire period of injection and lasts approximately 9.5 hours. When conducting deparaffinizing processing according to the proposed method is not needed at the end of the substitution fluid, or in the stop time to the end of the chemical reaction between the nitrogen-containing salts.Details of the method are summarized below.The process is continuous in multiple threads.The organization is reducing the initial flow of oil to 80%.The direction of pumping - mounted equipment - pipe - underwater monoboy - monoboy - tanker
End position of the processing liquid - pipe monoboy (21000 m).
The composition and preparation of the processing liquids, such as C+N solution and emulsion acid should provide a convenient procedure as mentioned in the section "prior art". Special attention should be paid to control the final pH of a solution of salts and stability activating emulsion acid. According to the present invention, a pilot project in seven adiabatic conditions shall be effective. For this experiment should be used samples prepared liquids and oil at a temperature such as at the exit of the separator.In addition, it should be noted that the temperature of the liquid resulting from deparaffinizing processing, should be measured in the stream to keep the dewaxing under control. Also should carefully be checked resulting fluid, as it becomes available on the tanker.After contact with the tanker, the paraffin content in the mixture of oils is no longer a problem, as the oil is stored in large volume. Subsequent paraffin will be placed on the walls of the vessel and can be easily removed by mechanical means.Description deparaffinization treatment given n>/BR>The organic solvent is a mixture of oils (wells 1, 2 and 3)
The percentage of solvent - 80% by volume (544 m3).The percentage of salt - C+N solution of 4.5 mol (or S+N solution).The percentage of the solution is 20% by volume (136 m3).The effective concentration of 0.9 mol.The activator of the reaction emulsion acetic acid @ 20%.The amount of activator - 1% of the total C+N solution.The flow of the processing liquid - 7.50 barrels per minute (generic).The flow of oil - 6.0 barrels per minute.Stream C+N solution of 1.5 barrels per minute
The flow activator - 0,63 g/min
Time pumping - 9,50 PMThe period of stop - 0
The maximum temperature is 98oC @ adiabatic; 93oC @ rated.The maximum pressure of 690 PSI @ the numerical calculations).It should be noted that the time of pumping depends on the volume of the treatment solution, which must be introduced into the pipeline to transport oil. This amount depends on the conditions of waxing is produced in the pipeline. At the beginning of processing, the pumping is more difficult, whereas after the inclusion of paraffin mass in the flow of oil pumping becomes easier, so that an Additional advantage of the present deparaffinizing way compared with the known methods, is the lack of a shutdown period (it is zero), which eliminates the need to stop operation of the pipeline. This is because deparaffinizing system works instantly - there is no cooling-off period in order deparaffinizing system has completely finished processing. This approach is not known and was assumed in the existing literature.The composition and preparation of machining fluids according to the present invention is shown below.Solution C+N (136 m3- assumption 1.Industrial water, m3and 88.5
Aluminium chloride, t - 32,8
Sodium nitrate, t - 42,2
Sodium hydroxide, kg - 150 (to pH 7.0)
A solution of S+N (136 m3- assumption 2.Industrial water, l - 272
Acetic acid 100%, l - 272
Diesel fuel, l - 816
Surfactant SGN/ON-LINE (680 m3), l - 13,6
C+N solution (or S+N solution), m3- 136
Oil, m3- 544
Emulsion acid, m3- 136
The application of a mixture of oils as a solvent for thermo-chemical dewaxing of a pipeline to transport oil on the platform of the basin Campos, state of R is ODEN. Mathematical calculations and experiments on the kinetics of reactions occurring in the flow of the mixture 80/20 volume/volume oil/C+N solution confirm the possibility of complete removal of organic deposits, probably present in the first half of 21,000-foot pipe.It should be noted that the salt solutions can be prepared based on ammonium chloride (C+N solution) or ammonium sulfate (S + N solution) or even from mixtures, providing appropriate molar ratio of salts.Thus, the present thermochemical method of dewaxing pipelines to transport oil provides the removal of paraffin deposits from these lines are very economical way, as this does not stop the production of oil. It also saves a significant amount of energy, given the fact that the heat extracted oil is part of the required heat.When applying the proposed method dewaxing under the terms of its implementation, those disclosed in the description and in the claims, enhances the flow of oil on the studied transporting pipeline from 1,700 cubic metres per day to 2,400 cubic meters per day, as oroposal thermo-chemical dewaxing of pipelines in the flow of transported oil on them using astheneia system, includes the following stages: a) defining a chamber (temperature appears paraffin) for samples extracted oil, the identification of the phenomenon of formation of paraffin sediments, as well as its localization in pipelines transporting oil; (b) determining the optimum amount of oil that should be used as a solvent available mass of paraffin in pipelines transporting oil, in order to carry out the dewaxing process; (C) preparation of heat and attenersi salt solutions and pilot test unit; (d) preparation of a solution of the activator delayed action; (e) continuous pumping from existing platforms in profilizirovannye pipeline, oil transporting, processing liquid received from the heat and attenersi salts, oil and activator slow steps, taken in the quantities specified in (C) thus, in order to carry out the process of dewaxing pipelines transporting oil, simultaneously with its production; (f) after injection fee of terminal waste liquid obtained after the processing of paraffin oil and aqueous waste solution in a liquid form.2. The method according to p. 1, the best of the tee from the separator for producing the platform.3. The method according to p. 1, characterized in that the degree of dilution capacity of the produced oil is detected by determining the weight ratio of oil and weight of paraffin, which is required for dissolving deposits of paraffin at a certain temperature.4. The method according to p. 1, characterized in that the oil used in the manufacturing of the liquid is oil produced from this field, such as oil from the separator on the platform.5. The method according to p. 1, characterized in that the heat generating and attractor nitrogen-containing salts include ammonium chloride and sodium nitrite, taken in equimolar ratio in molar concentration to 4.5 for each of the salts, as well as the activator.6. The method according to p. 1, characterized in that the heat generating and nitrogen a solution of nitrogen-containing salts include ammonium sulfate and sodium nitrite, taken in equimolar ratio in molar concentration to 4.5 for each of the salts, as well as the delayed action activator.7. The method according to p. 5 or 6, characterized in that the delayed action activator is 100% acetic acid, taken in bulk quantity 0,15-0,50% calculated on the total amount of the processing liquid.8. the kusnoy acid is 0.2% of the total volume of the processing liquid.9. The method according to PP.5 and 6, characterized in that the delayed action activator is an emulsion of water-in-oil, in which the dispersed phase is a 100% acetic acid and water, and the dispersing phase of the emulsion is an aliphatic hydrocarbon emulsified in a surfactant agent.10. The method according to p. 9, characterized in that the surface-active agent is a lipophilic surface-active agent.11. The method according to p. 10, characterized in that the lipophilic surface-active agent is a sorbitol ester, taken in an amount of 0.5 - 1.5% of the total volume of the activator.12. The method according to p. 9, characterized in that the volumetric amount of water and the volumetric amount of acetic acid in the dispersed phase of the emulsion in the same way.13. The method according to p. 9, characterized in that the aliphatic hydrocarbon, which is part of the dispersing phase of the emulsion water-in-oil, is pentane, hexane or heptane.14. The method according to p. 9, characterized in that the dispersing phase of the emulsion water-in-oil is a petroleum fraction such as diesel fuel.15. The method according to PP.9, 12 and 13, characterized in that the volume number oxynoe respectively.16. The method according to p. 15, characterized in that the preferred volumetric amount of acetic acid/water/ diesel emulsion water-in-oil is 20/20/60 respectively.