Method of determining freezing point of paraffins in oil
SUBSTANCE: oil sample is heated with one-time temperature control, the sample is continuously cooled with simultaneous measurement of shear stress. Chilling point is determined from temperature corresponding to the first abrupt increase in shear stress, and bulk freezing point is determined from temperature corresponding to the second abrupt increase in shear stress. The sample is heated to temperature of 60-80°C. Heating and temperature control of the sample is carried out while revolving the viscometer cylinder and the sample is cooled at a rate of 1-2°C per minute.
EFFECT: high information value and reliability of the analysis method.
The invention relates to the oil industry and is designed to determine the physical parameters of reservoir fluids can be used in industrial and research laboratories for determining the temperature of crystallization of the paraffin in the oil.
There is a method of determining the temperature of crystallization of the paraffin in the oil, which consists in the visual observation of the sample oil in transmitted polarized light using a microscope with continuous temperature control of the sample. For the crystallization temperature of the paraffin in the oil take the temperature corresponding to the appearance of bright dots on a black field of the considered sample of Mavlyanov CENTURIES, Markhasin I.L., Babalian G.A. Optical methods of monitoring the development of oil fields. - M.: Nedra, 1970. - 160 S.]. The disadvantage of this method is high subjective measurement error.
There is a method of determining the temperature of crystallization of paraffins, which consists in observing the change in transparency of a layer of the test sample when it is uniform cooling using solar cells with high sensitivity to red spectrum. The temperature of crystallization of the wax in the oil, take the temperature changes the transparency of the transparent layer [Mazepa B.P. the precipitation of paraffin oil gathering systems the field equipment. - M.: Nedra, 1986. - P.8].
The disadvantage of this method is the insistence to clean oil, for example, the content of mechanical impurities.
There is a method of determining the temperature of crystallization of the paraffin in the oil, which consists in observing the change in temperature of the cooled sample of the wax separated from the oil in time. For the crystallization temperature of the paraffin take the temperature value, which is fixed over a longer period of time on the background of the uniform reduction. [GOST 18995.5-73 chemical Products organic. Methods for the determination of the crystallization temperature. - P.15].
The disadvantage of this method is that for measurements requires the allocation of a sample of paraffin from the sample under test oil, which is time consuming and involves the use of hazardous and harmful substances, such as benzene, toluene, carbon tetrachloride.
There is a method of determining the temperature of crystallization of paraffins to change the attenuation coefficient of ultrasound in the sample oil, [Lusin SF, Stories, VA, Sheikh-Ali, D.M., and others Struggle with the deposition of paraffin in oil production. - M: COSTOPTIMIZED, 1961. - C.11].
The disadvantage of this method is the low reliability of the received data, as in the measurement process is the influence of ultrasonic vibrations on the sample itself, which distorts the received results.
There is a method of determining the temperature of crystallization of the paraffin in the oil using a rotational viscometer, taken as a prototype, including the placement of a petroleum sample in the measuring cylinder, step-by-step change of the sample temperature (usually at least 8 steps), the temperature of the sample at each step for 0.5 hour, the definition of the tangent shear stress at each measurement temperature for 0.5 hours, the calculation of the plastic viscosity, the construction schedule based plastic viscosity on temperature in semi-logarithmic coordinates, determine the temperature of crystallization of paraffins on the salient point of the graph [RD 39-0147103-329-86. The method of determining rheological parameters of the thickening of the oil. - Ufa: Vniisptneft, 1986. - P.12-13].
The disadvantages of the method include:
- the duration of the measurement (about 10 hours for one sample of oil);
the method allows to detect the beginning of crystallization, but does not determine the temperature of the mass crystallization of paraffins.
Object of the invention is to provide a method for determining the temperature of crystallization of the paraffin in the oil, which can eliminate the above-mentioned disadvantages of technical solutions.
The technical result of the invention is to reduce the time for the measuring, raising awareness and truth is the beginning of the method.
The task in the method of determining the temperature of crystallization of paraffins in crude oil, including the placement of a petroleum sample in the measuring cylinder rotational viscometer, the temperature change of the sample, thermo staterevenue sample, the definition of the tangent shear stress, is solved by the fact that they perform heating of the sample of oil with a single temperature control, continuous cooling of the sample with simultaneous measurement of the tangent shear stress, determination of the temperature of crystallization temperature of the first abrupt increase of the tangential shear stress, temperature determination of mass crystallization temperature corresponding to the second abrupt increase of the tangential shear stress, while the sample is heated to a temperature of 60-80°C, heating and temperature control sample perform with the rotation of the cylinder viscometer, and the cooling of the sample perform with the speed of 1-2°C per minute.
The claimed invention is illustrated in the drawing, which shows the dependence of the tangential shear stress from the temperature of the sample.
As explanations for the claimed method here is the following.
When the temperature control of the sample after heating to a temperature of 60-80°C is the destruction of supramolecular structures paraffins and translation paraffin is brazza in the liquid state. Upon further smooth decrease of temperature with constant speed and the temperature of crystallization of paraffin oil, there is a resistance to rotation of the cylinder rotational viscometer that is displayed by the registration device as a sharp increase of the tangential shear stress. In future work viscometer and the rotation of the rotor structure crystallized paraffins are destroyed to small, no resistance to rotation, and the recording instrument readings stabilize. The second abrupt increase of the tangential shear stress is indicative of a mass crystallization of paraffin oil. Thus, the first spike of values of the device corresponds to the formation of the first crystals, i.e. the temperature of crystallization of paraffins, and the second jump of the value - loss of a greater part of paraffin crystals in the sample, i.e. the temperature of mass crystallization.
It is necessary to set the temperature of the beginning and bulk crystallization of waxes petroleum sample, selected on acceptance point system pipeline JSC "Northern MN".
To determine the values of the temperature of the beginning and bulk crystallization of the sample was placed 25 ml of it into the cylinder 81 viscometer Rheotest RV 2.0. Then using a thermostat produce naked the EB samples to 80°C when the rotating cylinder viscometer. Upon reaching 80°C thermostatic sample of oil for 30 minutes. After the temperature is cooled sample at the rate of 1-2°C per minute with a constant rotation of the cylinder and the dimension of the tangent shear stress. Build a dependency graph of the tangent shear stress from the temperature of the sample. Determines that the temperature of crystallization of paraffins for the selected sample of oil is 48.8°C and the temperature of the mass crystallization of 39.7°C.
The method of determining the temperature of crystallization of paraffins in crude oil, including the placement of a petroleum sample in the measuring cylinder rotational viscometer, the temperature change of the sample temperature control of the sample, the definition of the tangent shear stress, wherein performing the heating of the sample of oil with a single temperature control, continuous cooling of the sample with simultaneous measurement of the tangent shear stress, determination of the temperature of crystallization temperature of the first abrupt increase of the tangential shear stress, temperature determination of mass crystallization temperature corresponding to the second abrupt increase of the tangential shear stress, while the sample is heated to a temperature of 60-80°C, heating and temperature control of the sample perform with the rotation of Zilin the RA viscometer, and the cooling of the sample perform with the speed of 1-2°C per minute.
FIELD: test engineering.
SUBSTANCE: body under study is brought into thermal contact with the reference body in the plane in which the local circular heater is located. At regular intervals of time the difference of values of the temperature between the heater and the point of plane of contact of the body under study and reference body is measured. The tests end up in excess of the specified value by the controlled dynamic parameter. The dependence of the current value of thermal activity on the temperature of the body under study is made. The structural transitions in polymeric materials are determined by the presence of peaks on dependence of the current value of the thermal activity on the temperature of the body under study.
EFFECT: improved method.
SUBSTANCE: method of determining volatility and heat of vaporisation of a mixture of liquid substances from the rate of evaporation from a flat surface involves establishing a correlation relationship between volatility values, calculated using known reference data, for individual liquid substances selected as calibration liquids, and the rate of evaporation thereof, determined based on data from thermogravimetric analysis carried out in isothermic conditions when an equilibrium state is achieved. The rate of evaporation of the analysed mixture is determined and the volatility value is found from the correlation relationship. The heat of vaporisation of the mixture of liquid substances in the analysed temperature range is determined using the relationship between the found volatility values and temperature. The value of the heat of vaporisation is determined from the value of the slope of a linear graph, the abscissa of which is the value of the inverse absolute temperature and the ordinate is the logarithm of the product of the experimentally determined volatility value and the absolute temperature value.
EFFECT: high reliability and objectivity of estimating volatility of not only individual liquids, but also mixtures thereof at different temperatures, broader functional capabilities of the method of determining volatility.
2 cl, 6 dwg
SUBSTANCE: method involves separate temperature control of cylindrical samples which make up a eutectic system, one of which has the analysed composition and the other is homogeneous, for example, consists of a pure substance. The samples are brought into contact at analysis temperature which is higher than the eutectic point, and the position of imaging point of the analysed alloy relative the solidus curve is determined from the state of the liquid layer formed between the samples.
EFFECT: invention enables more accurate plotting of a solidus curve on a phase diagram.
3 dwg, 1 tbl, 1 ex
SUBSTANCE: method of determining thermo-oxidative stability of lubricating materials involves heating the lubricating material in the presence of air and mixing. Oxidised lubricating material is then collected. Oxidation process parameters are then photometered and determined using graphical curves. Two samples of the lubricating material of constant weight are tested separately with and without a catalyst. While heating, the two samples of lubricating material of constant weight are tested successively with and without a catalyst, stirred while periodically varying testing temperature from temperature at the onset of oxidation and maximum temperature. Temperature is the lowered from maximum temperature to temperature at the onset of oxidation over a constant period of time. After each testing temperature, with and without a catalyst, the samples are weighed, the weight of the evaporated sample and evaporation number are then determined as a ratio of the weight of the evaporated sample to the weight of the remaining sample. By photometering, the light flux absorption factor with and without catalyst is determined, the thermo-oxidative stability factor is determined as a sum of light flux absorption factor and evaporation number. Further, the influence coefficient of the catalyst KVK on oxidative processes is determined using the formula KVK=KK/K, where KK and K are thermo-oxidative stability factors of samples of the lubricating material with and without catalyst, respectively. A curve of the influence coefficient of the catalyst on the oxidative processes versus the testing time is then plotted, and thermo-oxidative stability of the lubricating materials is then determined from values of the influence coefficent of the catalyst on the curve. If KVK>1, thermo-oxidative stability is falling, and if KVK<1 thermo-oxidative stability is increasing.
EFFECT: high information content of the method of determining thermo-oxidative stability of oxidation and evaporation processes during periodic variation of the testing temperature.
3 dwg, 1 tbl
SUBSTANCE: proposed method consists in measuring activity of acoustic emission signals emitted by tested specimen in heating. Polymorphic transformation temperature is defined as temperature corresponding to the moment of stepwise decrease in aforesaid activity.
EFFECT: higher accuracy and efficiency.
FIELD: instrument making.
SUBSTANCE: device for determining thermal stability of substances consists of cylindrical casing filled with warmth-keeping material, in which there coaxially placed is temperature-controlled metal cylinder with cavities made along its perimetre for arrangement of tightened reaction shells each of which is connected to pressure measurement and recording system. At that, each reaction shell is equipped with flame arrester and pneumatic drive connecting the reaction shell volume to pneumatic protector and precision temperature-compensated bipolar "pressure-voltage" converter which in its turn through multi-channel analogue-to-digital converter one of the inputs of which is connected to output of "atmospheric pressure-voltage" converter, is connected to pressure display and recording system. At that, in each pneumatic drive the provision is made for the tap which is equipped with valve connected to vacuum pump with automatic valve at the inlet, inert gas source and in-series connected pneumatic resistance and valve.
EFFECT: invention allows shortening the time and measurement period, calibration intervals, improves reliability at reducing overall dimensions and electric power consumption.
2 cl, 1 dwg
FIELD: instrument making.
SUBSTANCE: to investigate heat transfer in process of fluid metals cooling, a heat pipe is used, in which a heater of a heating zone is equipped with a controller and is arranged outside the pipe heating area. The heat pipe cooling area is made with a filling nozzle and a thermocouple arranged in it, and with cooling air. The cooling medium flow controller and the thermocouple for measurement of medium temperature are connected into the system of automatic control of the model operation. The device model is made with the scale M1=2÷5, where M1=la/lM, la - size of as-built heat pipe, lM - model size.
EFFECT: possibility to model cooling process.
SUBSTANCE: proposed vibro viscosimetric transducer reduces instability of amplitude and frequency of probe mechanical vibrations in analysing constant-viscosity fluids. Proposed transducer comprises probe mechanical current position pickup. Besides, it comprises mechanical vibration system rigidly coupled via rod with measuring spherical probe provided with thermocouple thermometre, and arranged on rigid base supporting electric exciter of mechanical oscillations of vibration system. Note here that said base is located inside outer temperature-controlled pickup casing and isolated thereof. Note also that mechanical vibration system is made up of two high-Q-factor vibration circuits rigidly fitted on the base to vibrate thereon, mainly, collinearly and linearly at close or equal resonance frequencies. Note here that exciter is arranged to interact only with vibrator provided with rod with measuring probe. Besides, mechanical vibration system represents a tuning fork with parallel operating and compensating vibrators.
EFFECT: reduced instability of amplitude and frequency of probe mechanical vibrations in analysing constant-viscosity fluids.
6 cl, 6 dwg
SUBSTANCE: signal simulator used is in form of at least micro-weighing chemically pure substances inside sealed cavities of a thermoacoustic waveguide rod (TAWR) with acoustic emission (AE) and temperature sensors, where the mass of said substances is determined with maximum accuracy and said substances have reversible anhysteretic temperature and energy of phase transitions (PT) of the first type (crystallisation/melting, evaporation/condensation), from which, in each cycle for heating and (or) cooling a sample in contact with the TAWR, by receiving AE signals of said PT and by simultaneously measuring contact temperature of the TAWR with the sample at PT points, temperature measurement channels and AE (sensors-amplifiers-converters) as a whole are checked and calibrated from temperature and energy characteristics of the PT of the first type of built-in thermodynamic acoustic-emission (TDAE) standards, by changing amplification coefficients or (and) threshold of sensitivity of measurement channels, or (and) amplitude-frequency characteristics (AFC) of temperature, electric and acoustic signal converters or (and) corresponding corrections when converting digital data to physical parameters. Possibility of TDAE standardisation is provided, which enables metrological support for thermal and (or) acoustic-emission analysis installations through dynamic and static inspection of their temperature and acoustic measurement channels.
EFFECT: increased reliability and accuracy of determining temperature and energy characteristics, stages for destruction of materials.
4 cl, 4 dwg
FIELD: power industry.
SUBSTANCE: method for determining slagging characteristics of ash for power station coals at flame combustion involves low-temperature ashing of the tested coal, manufacture of test sample from ash for investigation of physical ash properties at heating within temperature of 800°-1300°C with simultaneous fixture of deformation characteristics of the sample by means of measuring tool. Heating of sample in the above temperature interval is performed at constant heating rate of not less than 1.1 deg/sec, during which there determined is dependence of deformation speed of the sample on temperature of its heating; at that, temperature of beginning of ash slagging corresponds to maximum speed of sample deformation, and temperature of load-carrying flue gases at the furnace outlet corresponds to minimum deformation speed. Two to four test samples are subject to tests, and temperatures of the beginning of slagging and load-carrying flue gases at the furnace outlet are determined as arithmetic average of the appropriate values.
EFFECT: improving accuracy of determination of slagging characteristics of ash.
2 cl, 4 dwg
FIELD: measurement equipment.
SUBSTANCE: method is proposed to measure temperature using magnetisation of single-domain ferromagnetic nanoparticles as thermometric property from thermomagnetic materials with Curie temperatures in the range of varied temperature variation. Determination of temperature values and localisation of a point of its measurement are identified by position and form of a sensitive element image on a NMR tomogram.
EFFECT: expansion of functional capabilities.
FIELD: measurement equipment.
SUBSTANCE: sensitive element consists of substrate layer 4 made on the basis of gadolinium-gallium garnet, material layer 3 epitaxially grown on it, in which magnetostatic waves are spread, for example yttrium-iron garnet, converter 1 of electric signals to magnetostatic wave, constant magnet 5 located under substrate layer 4. A gap is formed between constant magnet 5 and substrate layer 4. Reflecting structures 2 are formed on both sides of converter 1 so that an envelope of pulse characteristic of converter 1 and reflecting structure 2 has, on one side of converter 1, maxima at the time moments corresponding to minima of the envelope of pulse characteristic of converter 1 and reflecting structures 2 on the other side of the converter of electric signals.
EFFECT: increasing sensitivity; reducing losses and enlarging the range of working frequencies above 3 GHz.
SUBSTANCE: method involves measuring heat production by variation of heat rate consumed by maintenance of the isothermal mode of a fermentation vessel with intermitted fluid and gas flows through the fermentation vessel with adjusted heat power consumption by mixing the culture fluid. It is combined with eliminating heat power consumption by heat production in the fermentation vessel of the culture fluid mass due to maintaining its initial value at the pre-set accuracy in the environment of the conducted continuous and periodic cultivation processes by equation of energy gain, consumed for each heating cycle of the fermentation vessel, the energy gain value derived by calibration heating of the fermentation vessel filled with the initial culture fluid mass with the heat production value and the maintenance of the culture fluid mass during the microorganism cultivation process are spread out over a period of time.
EFFECT: increased measurement accuracy of continuous and periodic microorganism heat production in the fermentation vessel.
2 cl, 3 dwg
SUBSTANCE: thermal detector has an illuminating and a receiving light guide, the first ends of which are connected to a light source and a photodetector, and second ends to a guided Y fibre-optic splitter, the common input/output of which is fitted with a heat-sensitive element, having a mirror surface and made in form of an opaque blind made from material with shape memory effect, attached by one end to the butt-end of a measuring light guide. The blind is given reversible shape memory at flexure. In the initial state, below the direct martensitic transformation temperature, the free end of the blind is tightly pressed by the mirror side to the butt-end of the measuring light guide, thereby completely covering the aperture of the light guide. In a state higher than the inverse martensitic transformation temperature, the free end of the blind deviates by an acute angle from the plane of the butt-end of the measuring light guide.
EFFECT: faster operation owing to reduction of the size and weight of the heat-sensitive element, simplification, reduced loss when transmitting reflected light flux to the receiving light guide and high sensitivity owing to significant change in intensity for small temperature changes.
FIELD: machine building.
SUBSTANCE: overheating indicator is made from alloy with shape memory effect and shaped to round washer of diameter Dw with screw hole of diameter D0. Initially, washer features flat shape with eight segments made by shaped radial and annular cutouts. Lp-long radial cutouts are made through 90 angular degrees running from water outer edges to change into annular cutouts diverging in both sides from radial cutouts. Reverse side of said indicator is coated with bright heat resistant elastic film. Alloy in region of segments is assigned a phase transition at design temperature into tubes of cylindrical geometry. Indicator geometrical characteristics are calculated from the following relationships: Lp=LK=D0=Dw/2π, Dc=LK/2π, where Dc is cylindrical tube diameter after phase transition. With significant thermal load acting on overheating indicator, washer reverse side coated with elastic heat resistant side becomes visible to facilitate perception. Note here that revolving, thus shaped, washer creates acoustic effect, that is, a peculiar whistle.
EFFECT: perfected design, higher safety.
FIELD: chemistry; biochemistry.
SUBSTANCE: proposed method can primarily be used in biotechnology, biochemistry and industrial microbiology. Fermentation apparatus are used to study growth and metabolism of microorganisms and for solving several other tasks. Proposed solution involves measurement within given time intervals of flow of liquid and gaseous media through a fermentation vessel at the beginning of the fermentation process and during the said process after selected time intervals necessary for measuring heat production of microorganisms and evaluating destabilising inputs of heat power from operation of apparatus for moving the culture fluid. Heat production is calculated as the increment of current values of heat power to the initial value of the measured heat power while making corrections for the effect of the said destabilising inputs. The method is realised in a fermentation apparatus in which a fermentation vessel is placed inside a controlled thermostating screen and is fitted with an additional mixing device for controlling temperature of the fermentation vessel. Pipes running to the fermentation vessel are in thermal contact with the controlled thermostating screen.
EFFECT: more accurate measurement of heat production of microorganisms in a fermentation vessel in continuous or periodic processes.
4 cl, 5 dwg, 1 tbl
FIELD: physics, control.
SUBSTANCE: invention is related to methods of automatic control of technological processes, in particular to system of nickel tetracarbonyl decay process control in hollow cylindrical device. Statistic adaptive model of 2nd order is used for control, which makes it possible to predict these parametres with sufficient metrological characteristics. Generated adaptive statistic model of the 1st order is used to calculate settings for temperature mode stabilisation circuits in device. Calculation is carried out as solution of optimisation task of mathematical programming with limitations in the form of inequalities. Obtained solutions are used as settings for temperature stabilisation controllers by zones of furnace that vary supply of electric energy and maintenance of specified values, besides special algorithmic solutions make operation of control circuits mutually independent on each other and invariant to external disturbances: flow and temperature of return gas CO and air temperature in workshop.
EFFECT: improved parametres of produced nickel powder quality.
FIELD: physics, measurement.
SUBSTANCE: thermal fuse (thermal indicator) refers to pyrometric technics for peak temperature testing of objects, hard-to-reach and actuated machine elements and can be applied in propulsion engineering where temperature of single structure components is to be measured. Technical result is reached by that thermal indicator is represented with crystalline chemical - phthalic anhydride with melting temperature +130.8°C and percentage in thermal indicator 100%.
EFFECT: design of thermal fuse (thermal indicator) allowing for ICE temperature overriding testing.
FIELD: measuring technique.
SUBSTANCE: method comprises using a contact pickup that is introduced into the substrate in the zone of incidence of the laser beam inducing the thermo-capillary convection in the liquid layer.
EFFECT: enhanced reliability.
FIELD: aids for protection against noise.
SUBSTANCE: anti-noise head phone can be used as aid for protection ears of human working under conditions of high acoustic noises and as aid being component of protection helmets etc. Anti-noise head phone has internal case provided with opening being size-adjusted and external case. Both cases are connected by connecting link. Device also has sealing shaft, onto different of which shaft the internal and external cases are connected correspondingly. Space between cases s filled with sound-absorbing facing. As facing the plates made of mineral cotton, like "Rockwool", on basalt basis can be used, or mineral cotton "URSA", either basalt cotton P-75, or glass cotton provided with facing made of glass felt, or foamed polymer like polyethylene or polypropylene. Sound-absorbing element has its total surface faced by acoustic transparent material, for example, with glass tissue of EZ-100 type or "Povyden" polymer for the first version. Plates on base of aluminum-containing alloys are used filled with titanium hydride or with air at density within 0,5-0,9 kg/m3 to have the following properties: compression strength is within 5-10 MPa, bent strength is within 10-20 MPa for second version. For the third version, members made of solid porous noise-absorbing material are used as noise-absorbing facing, which is namely foamed aluminum or metal ceramics, either metal plastics, or shell rocks with degree of porosity being within 30-45% range. According to fourth version, members with layer-by-layer reeling of porous threads, reeled upon acoustic transparent frame, like wire frame, are used. According to fifth version, crunches of solid vibration damping materials are used, for example, elastomer, polyurethane, or "Agat", "Antivibrit", "Shwim" type flexible PVC. Size of fractions of crunch is 0,3-2,5 mm.
EFFECT: higher noise protection.
5 cl, 3 dwg
FIELD: ferrous metallurgy; steel making process.
SUBSTANCE: pipe is made from doubled bushes closed at one end and open at other end. Both bushes are made from heat-resistant material possessing stability. Outer bush is provided with oxidation-resistance coat. Closed end of pipe is introduced into molten steel in such way that ratio of length of pipe below surface of molten steel to inner diameter of inner bush is equal to or exceeds 15 and ratio of said length to outer diameter of outer bush exceeds 3. Open end of pipe is connected with infra-red radiation detector. Temperature of molten steel is calculated by estimation of radiation emitted by inner bush at the end introduced into molten steel.
EFFECT: enhanced accuracy of measurements.
13 cl, 2 dwg