Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
  • F17D—PIPE-LINE SYSTEMS; PIPE-LINES
  • F17D1/00—Pipe-line systems
  • F17D1/08—Pipe-line systems for liquids or viscous products
  • F17D1/16—Facilitating the conveyance of liquids or effecting the conveyance of viscous products by modification of their viscosity
• • C—CHEMISTRY; METALLURGY
  • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
  • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G OR C10K; LIQUIFIED PETROLEUM GAS; USE OF ADDITIVES TO FUELS OR FIRES; FIRE-LIGHTERS
  • C10L1/00—Liquid carbonaceous fuels
  • C10L1/32—Liquid carbonaceous fuels consisting of coal-oil suspensions or aqueous emulsions or oil emulsions
  • C10L1/328—Oil emulsions containing water or any other hydrophilic phase
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T137/00—Fluid handling
  • Y10T137/0318—Processes
  • Y10T137/0391—Affecting flow by the addition of material or energy

Definitions

• Heavy oils are difficult to transport in pipelines under conditions of usual outside temperatures due to their very high viscosity. In order to increase their mobility, they are therefore often ohölen with low-R or mixed refinery sections; such a procedure requires relatively high additives in order to achieve a noticeable improvement in flow. In addition, such a process is only possible where light oil fields exist at the same location or where a nearby refinery can supply low-viscosity gasoline fractions.
• Another method also used is to add heat to the heavy oil in order to lower its viscosity and accordingly improve its fluidity, which requires considerable amounts of heat. So it is z. B. necessary, a heavy oil of 10.3 ° API, its viscosity at 20 ° C 40 000 mPa. s is to heat to a temperature of approx. 95 C in order to achieve a viscosity of approx. 100 mPa. s to achieve a threshold value frequently required for oil transportation in pipelines (ML Chirinos et al, Rev. Tec. Intevep 3 (2), 103 (1983). This means an extreme cost for the equipment and the supply of the pipelines and a loss from 15 to 20% of crude oil, since the necessary amount of heat is usually obtained by burning crude oil.
• Another method of heavy oil transport consists in pumping the oil through the pipes in the form of a more or less easily liquid emulsion. Since the viscosity of emulsions is largely determined by that of the dispersing agent, this is an oil-in-water emulsion.
• the oil-in-water Emulsion is obtained by adding water and emulsifier to the oil using shear forces and then pumping this mixture into the pipeline. In a settling tank, e.g. B. prior to entering the refinery, the emulsion is again separated into oil and water and the separated oil, the R Affinerie supplied.
• the lowest possible concentration of the emulsifier should lead to a stable, slightly liquid oil-in-water emulsion with a very high oil content, which naturally places high demands on the emulsifiers to be used. High shear forces must also be avoided during emulsification, since there is a risk of inversion to a water-in-oil emulsion that is extremely highly viscous in heavy oils.
• the emulsions are also said to be stable both to higher salinities such as occur in many deposit systems and to higher temperatures. Despite the stability of the emulsions as they flow through the pipeline, they should be able to be separated again without any problems. Sulfur-containing emulsifiers are undesirable if they fail to be kept in the aqueous phase during the cleavage.
• carboxymethylated oxethylates of the formula are used as emulsifiers in which R is a linear or branched aliphatic radical having 6 to 20 carbon atoms, an alkyl or dialkyl aromatic radical having 5 to 16 carbon atoms per alkyl group, n is 1 to 40 and M is an alkali metal or alkaline earth metal ion or ammonium.
• the carboxymethylated oxethylates according to DE-PS 24 18 444 are advantageously prepared by reacting oxethylates of the formula with chloroacetic acid or a salt of chloroacetic acid in the presence of alkali hydroxide or alkaline earth hydroxide.
• R is preferably a saturated or unsaturated, straight-chain or branched alkyl radical having E to 18 C atoms or an alkylaryl radical having 5 to 16 C atoms in the alkyl group or a dialkyl radical having 3 to 16 C atoms per alkyl group.
• alcohols whose oxethylates are carboxymethylated, z. B.
• hexyl alcohol hexyl alcohol, octyl alcohol, 2-ethylhexyl alcohol, nonyl alcohol, isononyl alcohol, decyl and undecyl alcohol, lauryl, tridecyl, myristile, palmityl and stearyl alcohol, but also unsaturated, such as B. oleyl alcohol.
• alkylphenols such as B. Insert: P entylphenol, hexylphenol, octylphenol, nonylphenol, dodecylphenol, hexadecylphenol, and the corresponding D ialkylphenole.
• Alkyl cresols and xylenols are also suitable.
• the oxethylation can be carried out in the presence of catalytic amounts of alkali metal hydroxide, but it is known that other processes are also possible.
• the degree of oxyethylation can assume values between 1 and 40, preferably between 3 and 20.
• the cation in carboxymethylated oxyethylate with the formula can be sodium, potassium, lithium, ammonium, calcium, magnesium or hydrogen.
• the emulsifiers used are predominantly anionic, so that an unproblematic cleavage of the emulsion stabilized by them can be assumed.
• the compounds are thermally stable and, within extremely wide limits, are compatible with salt water (US Pat. No. 4,457,373).
• hydrophobic residue and the degree of oxyethylation they allow the emulsifier to be optimally adapted to the oil to be transported and the given salinity of the water conveyed from the deposit in most cases, which advantageously forms the aqueous phase of the emulsion to be transported.
• the carboxymethylated oxethylates can contain unreacted oxethylate. Accordingly, a degree of carboxymethylation can be defined.
• Mixtures with a degree of carboxymethylation between 85 and 100% are particularly effective. Such mixtures accordingly consist of anionic and nonionic surfactant and are considered as carboxymethylated oxethylates according to the invention.
• mixtures of anionic and nonionic surfactant described or the purely anionic compounds (emulsifier) are soluble or at least easily dispersible in conventional reservoir waters.
• the emulsifier to be used can be optimally adjusted to the existing heavy oil-water system according to its chemical structure.
• the surfactants (emulsifiers) of a homologous series (cf.Table A) are dissolved in the water in question and mixed with the heavy oil in question and, after briefly stirring with a paddle stirrer without using high shear forces, they are tested for their emulsifying action and the stability of the emulsion is determined. This assessment of the emulsion is repeated about 24 hours later and then the viscosity is measured as a function of the shear rate, if necessary. Since heavy oil emulsions are somewhat structurally viscous, a range between 1 0 and 100 sec 1 is selected for the shear rate, which corresponds approximately to the transport through pipelines.
• a surfactant is an optimal emulsifier if the amount necessary for emulsification is as small as possible.
• the amount is generally from 0.01 to 0.5, in particular from 0.03 to 0.2,% by weight, based on the amount of oil, which corresponds to 100 to 5000, preferably 300 to 2000, ppm.
• the emulsifier is either metered in as a melt or as an aqueous solution or as a dispersion of the oil-water mixture, or else it is added to the water, which is then mixed with the oil.
• Water here is understood to mean either a more or less saline water that is produced together with the heavy oil, or it can be a cheaply available surface water or, finally, a mixture of both waters. Since heavy oil fields are often exploited by steam flooding, the salinity of the water produced can fluctuate somewhat, which is not critical for the claimed process.
• the emulsifier can also be added to the heavy oil itself, especially since the surfactant class claimed here shows good oil solubility. It may be advantageous to use a small amount of a light hydrocarbon mixture as a solubilizer.
• the mixing of the three components to form the emulsion, namely oil, water and emulsifier, can take place either directly at the borehole or in or near a collection tank or at any other point in the piping system.
• the mixture ratio of oil to water can vary within wide limits between 10:90 and 90:10. For economic reasons, high oil contents should be aimed at, although it must be taken into account that very high oil contents usually also lead to relatively highly viscous oil / water emulsions.
• the economic optimum is between 70 and 85% oil.
• the emulsification is favored by mixing devices such as agitators, centrifugal pumps, static mixers, etc., which are used when necessary.
• the E multi- sion thus formed is conveyed through the pipe system, the which can contain intermediate stations and intermediate storage containers.
• the emulsion is split in a separator, it being advantageous to add one or more desmulsifiers.
• the crude oil dewatered in this way is drawn off and then either to the refinery or a possible further transport, e.g. B. supplied by ship.
• the effectiveness of the surfactant can be optimized by varying the chemical structure (change in the degree of EO).
• Carboxymethylated nonylphenol oxethylates with an EO degree of approx. 3.3 have the highest effectiveness here.
• the viscosity is around 100 mPa. s at 20 ° C - 100 mPa are required. s at 37.7 ° C - very low.
• Table B examines the effect of the same surfactants in the presence of high saline water (50,000 ppm NaCl).
• the EO grade of the most effective surfactants is between 5.5 and 6.0.
• the significantly increased effectiveness compared to the lower salinar conditions in Table A is surprising
• Table E shows the dependence of the emulsifying activity in the case of a carboxymethylated nonylphenol oxethylate on the degree of carboxymethylation.
• the influence of alkaline earth ions is also examined. The effectiveness increases with increasing degree of carboxymethylation. This also applies in the presence of alkaline earth metal ions, which otherwise have a high emulsifying effect Reduce basic salinity more than additional alkali halides in the same concentration.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Health & Medical Sciences (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Public Health (AREA)
• Water Supply & Treatment (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Emulsifying, Dispersing, Foam-Producing Or Wetting Agents (AREA)
• Liquid Carbonaceous Fuels (AREA)
• Colloid Chemistry (AREA)

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• 1984
  • 1984-09-27 DE DE19843435430 patent/DE3435430A1/de not_active Withdrawn
• 1985
  • 1985-07-27 EP EP19850109481 patent/EP0175879B1/fr not_active Expired
  • 1985-07-27 DE DE8585109481T patent/DE3568346D1/de not_active Expired
  • 1985-09-25 CA CA000491508A patent/CA1242952A/fr not_active Expired
  • 1985-09-27 US US06/780,877 patent/US4736764A/en not_active Expired - Fee Related

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