104 results about "Liquid density" patented technology

The invention relates to the technical field of industrial automation control, in particular to a container liquid level measurement method, system and equipment of a pressure sensor and a medium, and provides a method for eliminating gas phase pressure influence based on a double-sensor differential measurement mechanism and dynamically correcting liquid density and sensor drift errors in combination with a temperature compensation model. The temperature data are linked in real time through a three-dimensional compensation function, density calculation and drift correction are synchronously adjusted, and multi-parameter dynamic decoupling and self-adaptive compensation are achieved; a collaborative measurement mechanism is adopted to integrate bottom and top sensor data, and a built-in temperature probe and a preset threshold are combined to complete multi-source signal fusion and compensation calculation; a dynamic calibration method is designed, and system errors are eliminated through reference pressure point calibration and structure coefficient correction; constructing a closed-loop signal processing flow, and integrating high-precision analog-to-digital conversion, digital filtering and real-time algorithm to output a compensated liquid level value; the method improves the measurement precision and stability, and is suitable for temperature change, gas phase pressure fluctuation and multi-medium scenes.

The invention discloses a single-ultrasonic-head sensor for measuring liquid density and liquid level height, which relates to the technical field of liquid level measurement and comprises a floater component, a reflection cavity component and an ultrasonic sensor component. The floater assembly is assembled on the reflection cavity assembly, the reflection cavity assembly is connected with the ultrasonic sensor assembly, and the ultrasonic sensor assembly is connected with the floater assembly through the reflection cavity assembly. High-frequency ultrasonic waves are transmitted and received through a single point, the sound velocity (density) and the ultrasonic wave return time difference (liquid level) are synchronously analyzed, the density and the liquid level of the urea solution are calculated, the problems of mechanical interference and data splitting are avoided, and the trepanning and cable cost is reduced; the shared high-precision temperature compensation module directly eliminates compensation deviation of the split system, and maintenance only needs single-point anti-crystallization treatment; and in combination with a cross validation algorithm (density liquid level logic mutual verification), the operation and maintenance cost is reduced while the data reliability is improved, and the method is particularly suitable for space-limited and highly-corrosive urea solution detection scenes.

The invention discloses a liquid density measuring device and method and electronic equipment, and relates to the field of density measurement, the device comprises a metal base, a metal vibration platform, a measuring pool and a driving sensor, the measuring pool comprises a glass sealing shell, a U-shaped tube, a reference oscillation tube, a vibration acquisition sensor and a temperature acquisition device, and the U-shaped tube is used for filling measured liquid; the reference oscillation tube is not filled with liquid; the U-shaped tube, the reference oscillation tube, the vibration acquisition sensor and the temperature acquisition device are all arranged in the glass sealing shell; the measuring cell is arranged on the metal vibration platform, and the metal vibration platform is arranged on the metal base; the driving sensor is arranged in the metal base and located below the metal vibration platform, so that the metal vibration platform is conveniently driven to generate mechanical oscillation. Through the glass sealing shell, the influence of the external environment is reduced, the density is calculated at a proper temperature, synchronous oscillation of the U-shaped tube and the reference oscillation tube is ensured, density compensation is ensured, and the liquid density measurement precision is effectively improved.

The application belongs to the technical field of liquid density detection, and discloses a base liquor density detection method for an automatic blending system and related equipment. The method comprises the following steps: acquiring a solvent capacity identifier of current base liquor to be delivered and a residual risk identifier of the last batch of delivered base liquor, judging whether a preset pollution risk time sequence combination exists in a delivery sequence; if the pollution risk time sequence combination exists, delivering the current base liquor to be delivered at a preset flow rate, and collecting a first density measurement value in a first measurement period; then, making the liquid in the delivery pipeline stand still for a preset length of time; then, delivering the current base liquor to be delivered at the preset flow rate again, and collecting a second density measurement value in a second measurement period; calculating a density difference value according to the first density measurement value and the second density measurement value; according to a comparison result of the density difference value and a preset dissolution effect determination threshold, confirming the true intrinsic density of the current base liquor to be delivered; and thus the accuracy and reliability of density detection are improved.

Method and system for determining a mass of a liquid in a container and / or a conduit, in particular a fuel in a tank of an aircraft. One aspect of the invention relates to a method for determining a mass of a liquid in a container and / or a conduit (1), for example a tank, at least one sensor (11), the mass of the liquid being determined from the density of the liquid and the level of the liquid in the container and / or the conduit, the density being determined from an estimation of the temperature of the wall (2), the propagation speed of a second propagation mode of a guided elastic wave propagating in the wall of the container or conduit below the level of the liquid and a dispersion curve of this second propagation mode. Figure to be published with the abstract: Figure 1

The utility model relates to the technical field of liquid medicine measuring equipment, and discloses a novel liquid medicine density measuring device which comprises a metering scale, a bearing plate and a bracket, one side of the metering scale is connected with a plurality of fixing blocks, a pressure sensor is arranged between the fixing blocks, one end of the support is connected with the pressure sensor, one side of the bearing plate is connected with the fixing blocks, one side of the bearing plate is connected with a plurality of side plates, the side plates are transversely connected with first screws, and the first screws are connected with second screws. A measuring cylinder is arranged between the first screw rods, one end of each first screw rod is connected with a clamping plate, and one side of each clamping plate is attached to the measuring cylinder; one end of the support is transversely connected with a transverse rod, the transverse rod is sleeved with a hook, one end of the hook is connected with a densimeter, the side, away from the hook, of the densimeter corresponds to the measuring cylinder, second screw rods are arranged on the two sides of the transverse rod, the second screw rods are transversely connected to the support, and the second screw rods correspond to the hook.

The application discloses a method for measuring liquid density by using optical active solution, which comprises a laser, a polarizer, a liquid to be measured, an optical active solution, a transparent water tank, an electronic balance, an analyzer and a light screen. γ The optical active solution is filled in the transparent water tank with a length of l, and the mass of the optical active solution is γ, the mass of the solute is γ1, and the density is ρ X A certain mass (X) of the liquid to be measured is added, and after being uniformly stirred, the optical activity α of the mixed solution is measured by rotating the analyzer and the light screen; the relationship between X and α is obtained, that is, the data are linearly fitted by using a graphing method, and the density ρ X of the liquid to be measured is calculated by the slope of the straight line. The application is a method for measuring liquid density, and has clear physical principle, simple measurement process, high measurement accuracy and high repeatability.

The utility model discloses a simple liquid density proportioning instrument which comprises a working table, three placing grooves are formed in the upper surface of the working table at equal intervals, first beakers are placed in the placing grooves respectively, a mixing mechanism and a rotating disc are sequentially installed at the upper end of the working table, a second beaker is placed in the mixing mechanism, and the rotating disc is installed on the working table. An automatic pipetting work station is arranged above the workbench, a first electric guide rail is installed in the middle of the side, away from the automatic pipetting work station, of a second electric guide rail, an air cylinder is fixedly connected to the upper end of the workbench, a third electric guide rail is fixedly connected to the upper end of the air cylinder, and a connecting rod is installed on the surface of the third electric guide rail. Liquid needed by density matching is stored through the first beaker, the second beaker is used for matching the liquid, the automatic pipetting work station sucks the liquid in the first beaker and the liquid in the second beaker, the mixing structure enables the liquid in the second beaker to be mixed, and automatic matching is achieved.

An acoustic wave sensor (1) for waves propagating in a liquid is optically sensitive to variations in the liquid's density caused by pressure changes associated with the passage of an acoustic wave. The sensor is designed to be threaded through a wall (102) of a pipe, for example, in a water distribution network. The sensor is useful for detecting liquid leaks at a distance from its installation location, or for adjusting the intensity of an acoustic wave used to unclog a deposit on a surface in contact with the liquid. (Abstract figure: Figure 2)

The application discloses a kind of water bottom waste liquid self-adaptive collection device and waste liquid collection method, belong to environmental protection technical field.The application includes with the cover opening device and cover closing device of waste liquid recovery barrel cover connection;Utilize the pressure and density variation of water to start cover opening device and cover closing device, realize the automatic opening and closing of waste liquid recovery barrel cover.The application is realized automatic control by spring mechanism and float action in working box.The application utilizes the pressure and waste liquid density variation of water, automatically adjusts spring pressure, to drive gear system to perform cover opening and closing operation, the design of eccentric hole ensures the unidirectionality and stability of gear movement, avoids the possibility of reverse movement or misoperation, enhances the reliability of device in complex underwater environment.

The present invention relates to the technical field of coal mine gangue slurry filling, and provides a device and method for monitoring the diffusion range of slurry inside a goaf during the slurry filling process. Inside the goaf, the slurry seeps into the liquid collection cylinder body, and the change in the liquid density inside the cylinder body is monitored in real time through a liquid density monitoring device, and the monitoring data is transmitted to the ground data monitoring system in real time through an armored cable. The permeable slurry plate is installed on the top of the liquid collection cylinder body, effectively isolating the caving gangue in the goaf, and at the same time ensuring that the slurry enters the liquid collection cylinder body. The structure of the present invention is simple, easy to install, has a small engineering quantity, and high data information accuracy, avoiding the cumbersome work of drilling construction and sampling, and being able to master the diffusion range of the slurry in the goaf in real time while the slurry is being filled. The device is pre-buried behind the support in advance according to a certain row and column spacing along with the mining of the working face, and the armored cable for transmitting data is connected to the ground data monitoring system in advance by using the roadway of the working face, forming a slurry diffusion monitoring system.

Methods, apparatus, and systems for determining a level of a liquid in a liquid-containing vessel are disclosed. The liquid-containing vessel may be fluidically connected to a displacer cage. The method may include obtaining, with a load measurement device, a weight force of a displacer suspended from the load measurement device and disposed within the displacer cage. The method may also include submerging the displacer into the liquid and obtaining, with the load measurement device, a net force acting on the displacer. The method may further include obtaining, with a liquid density measurement sensor disposed within the displacer cage, a liquid density at a first location of the liquid. The method may still further include determining, using, at least, the net force and the liquid density at the first location of the liquid, the level of the liquid in the vessel.

The utility model discloses a pressure type on-line liquid densimeter, which relates to the field of perchloric acid densimeters and comprises a densimeter body, a tank body is arranged on the top surface of the densimeter body, a second connecting pipe is fixed and communicated with the bottom of the tank body, and the bottom end of the second connecting pipe is fixed and communicated with the top of the densimeter body. According to the utility model, the first valve body is arranged, different pressures can be preset through the arrangement of the first valve body, density measurement can be carried out in a stable pressure environment, the stability and repeatability of a measurement result can be ensured, and the quality and reliability of data can be improved; the working pressure of equipment can be effectively stabilized through the arrangement of the first valve body, a sensor and a measuring element in the densimeter body are prevented from being damaged due to too high or too low pressure, the opening or closing state can be automatically adjusted according to the actual pressure condition in a pipeline through the automatic adjusting function of the first valve body, the stability and reliability of the system are ensured, and the practicability is high. And problems caused by manual misoperation or system faults are reduced.

The invention discloses a chemical liquid density measuring and preparing device and method. The device comprises a measuring assembly and a liquid feeding assembly. The measuring assembly comprises a density measuring container and a weighing sensor, the weighing sensor is configured to be capable of measuring the weight of the density measuring bottle, and a lowest liquid level sensor is arranged on the density measuring container; the liquid feeding assembly comprises a first rotary valve and at least two kinds of chemical liquid, the first rotary valve is connected with the density measuring container through a connecting pipeline, the first rotary valve comprises a first closing valve port and at least two liquid feeding valve ports, and the chemical liquid is connected to the corresponding liquid feeding valve ports through respective pipelines; a liquid flowmeter and a switch valve are arranged on the connecting pipeline, and at least one end, close to the density measuring container, of the connecting pipeline is fixedly arranged, so that the weight measurement of the density measuring container is not influenced by the connecting pipeline. According to the scheme, mixed liquid preparation and density measurement are integrated, high efficiency and convenience are achieved, and potential safety hazards do not exist.

The invention relates to a liquid level metering method of a liquid level meter, which comprises the following steps: receiving pressure data detected by a first pressure sensor and a second pressure sensor, and judging the position of an oil liquid level; calculating the inclination angle of the probe according to the pressure data; the distance between the first pressure sensors is corrected according to the calculated inclination angle, and the actual height is obtained; the liquid density between the first pressure sensors is calculated according to the received pressure data and the actual height, and the position of an oil-water interface is judged according to the calculated liquid density; according to the liquid density and pressure data, the distance between the first pressure sensor and the oil liquid level is calculated, and the height of the oil liquid level is obtained; the sum of the pressure intensity of the water and the pressure intensity of the oil is the detection result of the first pressure sensor at the tail end of the detection rod, the sum of the water layer height and the oil layer height is the liquid level height, the water layer height and the oil layer height are obtained, and the oil volume is obtained by comparing the tank capacity meter of the oil storage tank. The metering method is accurate in metering, high in precision and high in reliability.

The application discloses a kind of single ultrasonic head measuring liquid density and liquid level sensor, it is related to the technical field of liquid level measurement, including: float assembly, reflection cavity assembly and ultrasonic sensor assembly;Float assembly is assembled on reflection cavity assembly, reflection cavity assembly and ultrasonic sensor assembly are connected, and ultrasonic sensor assembly is connected with float assembly by reflection cavity assembly.The application transmits and receives high-frequency ultrasonic wave by single point, synchronously analyzes sound velocity (density) and back ultrasonic wave time difference (liquid level), and calculates the density and liquid level of urea solution, avoids mechanical interference and data fragmentation problem, reduces the cost of opening and cable;High-precision temperature compensation module is shared to directly eliminate the compensation deviation of split system, maintenance only needs single-point anti-crystallization treatment;Combined with cross-validation algorithm (density liquid level logic mutual inspection), while improving data reliability, reduce operation and maintenance cost, especially suitable for space limited, strong corrosion urea solution detection scene.

The utility model discloses a well fluid collecting device of a well logging standard well, which comprises an annular mounting cover connected to the end part of the well logging standard well, one side of the annular mounting cover is connected with a liquid density sensor and a U-shaped transmission pipe, and the U-shaped transmission pipe is connected with a first control valve and a cyclone hydraulic separator used for separating liquids with different densities. The high-density liquid output end of the cyclone hydraulic separator is connected with a well killing fluid transfer box through a first pipeline, the low-density liquid output end of the cyclone hydraulic separator is connected with a shaft outlet liquid collecting box through a second pipeline, the well killing fluid transfer box is provided with a power pump which is connected with an output pipe, the output pipe is connected with an extension pipe, and the first pipeline is connected with a second control valve. The extension pipe is connected with a third control valve.

An apparatus and method are provided for optimizing the use of gas hydrate inhibitors by combining real-time "dew point" measurement with quantum-chemical phase-change analysis. A gas hydrate inhibitor reduces gas moisture; by measuring gas humidity and identifying the "dew type" using two chilled-mirror sensors each equipped with an imaging camera, a "dew coefficient" (0–1) is calculated via quantum chemistry analysis of inhibitor solvation. This mesoscale coefficient is used to monitor fluid phase changes. A general relationship for the water / hydrocarbon "dew coefficient" is derived as a function of changes in Gibbs free energy of dew evaporation (inhibitor solvation), gas temperature and pressure, and gas / liquid density. By combining measured "dew point" and "dew type" with quantum chemistry data of phase transformations "dew coefficient", the optimal inhibitor injection rate is determined, minimizing inhibitor consumption while preventing hydrate formation.

The invention discloses a liquid density monitoring method and device, electronic equipment and a storage medium, and relates to the technical field of control, slurry differential pressure signals are collected by means of a preset differential pressure measurement assembly, the density is calculated, and meanwhile measurement, flushing and pollution discharge execution assemblies are connected into an automatic control system to form a closed-loop control process. Sediment accumulation caused by slurry solid content change in long-term operation can be reduced through flushing and pollution discharge, and differential pressure signal fluctuation is avoided; the density value can be dynamically corrected based on historical data and working condition parameters to improve the measurement accuracy, fault self-diagnosis and alarm prompting are achieved by setting fault judgment conditions, manual inspection and experience judgment are replaced, the response speed is increased, and the measurement accuracy is improved. The technical effects of reducing slurry sediments, stabilizing differential pressure signals, reducing the maintenance cost, improving the desulfurization efficiency, avoiding the non-planned shutdown of the system and enhancing the operation stability of the desulfurization absorption tower are achieved.

1. The name of the design product: table type density meter. 2. The use of the design product: for measuring liquid density, alcohol content, sugar content, salinity. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

The application provides a method for measuring the saturated surface dry water absorption rate of concrete coarse aggregate, which mainly uses an oven, a metal mesh basket, a beaker, an electronic balance and other tools, constructs a quantitative relationship model of relevant parameters according to the mass change of the coarse aggregate before and after being soaked in different liquids, and calculates the saturated surface dry water absorption rate of the concrete coarse aggregate. The application is based on the pore structure characteristics and capillary adsorption characteristics of the coarse aggregate, uses the difference in the absorption capacity of the coarse aggregate for different liquids, and the difference in the density and the viscous coefficient of different liquids, and designs the method for measuring the saturated surface dry water absorption rate of the concrete coarse aggregate. The method has the characteristics of simple steps, low cost, reliable test, stable data, easy popularization and the like, overcomes the defects of the traditional method, such as large human operation error and serious subjective experience influence, and can be used for the research and development of automatic equipment and the design of software algorithm, and has good popularization and application value.

The invention provides a float type liquid level monitoring method and device, a medium and a product. According to the method, a control processing unit firstly obtains preset parameters of a floater, initial liquid density and a real-time height value of a height sensor, and a basic data system is constructed for subsequent calculation. And the control processing unit generates a reaction rate curve by using the initial liquid density and the chemical reaction rate equation, and deduces a curve of the mixed liquid density along with the time change through the reaction rate curve, so that the pre-judgment of the dynamic change of the liquid density is realized. Then, the control processing unit calculates the immersion depth in combination with the current density and floater parameters, the liquid level distance is obtained through the distance difference between the height sensor and the bottom of a floater, and finally the actual liquid level is calculated based on the real-time height of the sensor and the liquid level distance. According to the method, the density change is dynamically tracked, errors caused by the immersion depth of the floater are corrected in a targeted mode, the problem of monitoring deviation caused by the density dynamic change is effectively solved, and the accuracy of liquid level monitoring is improved.

The invention relates to a liquid level metering method of a liquid level meter, which comprises the following steps of: receiving pressure data detected by first pressure sensors at different heights on a probe and a second pressure sensor arranged at the top end of the probe, and judging the position of an oil liquid level according to the received pressure data; the liquid density between the first pressure sensors is calculated according to the received pressure data detected by the first pressure sensors, and the position of an oil-water interface is judged according to the calculated liquid density; the distances between the first pressure sensors and the oil liquid level are calculated according to the liquid density between the first pressure sensors and pressure data detected by the first pressure sensors; the height of the oil liquid level is determined according to the distance between the first pressure sensor and the oil liquid level and the height of the first sensor on the probe; the water layer height and the oil layer height are obtained by solving the liquid pressure calculation formula and the liquid level height calculation formula, and the oil volume is obtained by comparing the tank capacity table of the oil storage tank. According to the metering method, the metering accuracy can be improved.

The invention belongs to the technical field of floating and sinking, and discloses a floating and sinking multi-density-level heavy liquid density adjusting and preparing device which comprises a first liquid barrel. The first liquid barrel is used for preparing heavy liquid with target density; a first pipeline is connected to the outer side of the first liquid barrel, a liquid inlet and a liquid outlet of the first pipeline are communicated with the interior of the first liquid barrel, and a solution in the first liquid barrel enters the first pipeline from the liquid inlet; a first pump part and a density monitoring part are connected in series in the first pipeline; the first pump part is used for pumping the solution in the first pipeline to the liquid outlet and enabling the solution to flow back into the first liquid barrel; the density monitoring part is used for monitoring the density of the solution in the first pipeline; the first liquid barrel is connected with a first liquid conveying unit and a second liquid conveying unit; the density monitoring part continuously monitors the solution flowing in the circulation loop, online, real-time and global measurement of the heavy liquid in the first liquid barrel is achieved, the accuracy and reliability of density modulation or preparation are remarkably improved, and modulation or preparation of heavy liquid of various density levels can be achieved according to actual needs.

The invention relates to the field of ship engineering, in particular to a method for designing the mounting position of an underwater bubble generating device. Comprising a bubble scale determination process, a bubble rising speed determination process and a spray pipe installation distance determination process. According to the method, collaborative optimization of the bubble scale, the rising speed and the spray pipe layout is realized through multi-parameter coupling modeling. Establishing a static water bubble volume dynamic model based on liquid density, gas flow and nozzle diameter, and accurately calculating bubble diameter in combination with a transverse water flow correction factor; quantifying a bubble rising speed by adopting an empirical formula; and a nozzle interval dynamic adjustment model with the proportionality coefficient as the core is constructed, and the coverage rate is determined through displacement of bubbles in water flow, so that accurate design of the installation position is achieved. The innovation point lies in a multi-field decoupling modeling technology and a coverage rate quantification regulation and control mechanism, the limitation of the prior art is broken through, and the method is suitable for the fields of ship drag reduction, noise reduction, ocean engineering and the like.

Fluid product dispensing device comprising a metering valve mounted on a reservoir (1) containing at least one active ingredient suspended in a pressurized propellant gas whose liquid density at 21°C is less than or equal to 1.20 g / cm3, said valve comprising a valve body (10) containing a metering chamber (20), and a valve (30) sliding axially in said valve body (10) between a rest position and a dispensing position, to dispense the contents of said metering chamber (20), said metering chamber (20) being, in the rest position of the valve (30), connected to said reservoir (1), to allow the filling of the metering chamber (20) by gravity when, in the rest position of the valve (30), the valve is in an inverted position with the metering chamber (20) arranged below the reservoir, and to allow the emptying of said metering chamber (20) by gravity when, in the rest position of the valve (30),the valve is in an upright position with the metering chamber (20) arranged above the reservoir, said valve body (10) comprising at least one fluid passage opening (11), defining a passage surface S1 connecting said reservoir (1) to the interior of said valve body (10), said passage surface S1 being greater than or equal to 20 mm² and less than or equal to 100 mm². "figure for the abstract: figure 1",

The invention discloses an MVR evaporator system which comprises an evaporator, a compressor, a liquid separation unit and a control unit. Wherein the bottom of a liquid separation cylinder of the liquid separation unit is provided with a liquid separation cylinder conveying port, the liquid separation cylinder conveying port is communicated with a bottom discharge port of the evaporator through a first branch, and the first branch is provided with a first bottom valve; the delivery port of the liquid separation cylinder is further connected with a second branch communicated with the outside of the system, and a second bottom valve is arranged on the second branch; the first density sensor is used for measuring the liquid density rho 2b at the bottom of the liquid separation cylinder in real time; the control unit is configured to control the opening and closing states of the first bottom valve and the second bottom valve at least based on rho 2b after liquid in the liquid separation cylinder is subjected to standing layering, so that heavy-component pollutants located on the lower layer and light-component pollutants located on the upper layer after standing layering are discharged to the outside of the system through the second branch, and the heavy-component pollutants located on the lower layer and the light-component pollutants located on the upper layer are discharged to the outside of the system through the third branch. And the liquid in the middle layer is conveyed back to the evaporator through the first branch. According to the evaporator system, the evaporator can still continuously evaporate under the condition of high concentration of wastewater, and the treatment efficiency of the system is greatly improved.

The present application relates to the technical field of ore pulp processing, and particularly relates to a kind of ore pulp and reagent mixing and settling device and working method thereof, device includes mixing reaction mechanism, screen mechanism, settling mechanism and mud outlet mechanism, mixing reaction mechanism includes reaction bucket and vortex guide plate in it, bucket cover and reaction bucket side wall are respectively provided with medicine inlet and feed inlet;Reaction bucket bottom is communicated with settling barrel by spiral discharge pipe;Settling mechanism includes settling barrel and water suction port, and water suction port inlet is arranged in settling barrel, and located above screen;Mud outlet mechanism includes spiral blade, mud outlet and mud pump.The present application is provided with spiral vortex guide plate and staggered side baffle, combined with spiral discharge pipe and discharge baffle, so that ore pulp and reagent complete sufficient mixing, stirring and reaction in conveying process;By setting multiple densitometers, the liquid density at each position in the settling barrel is monitored in real time, so as to automatically adjust according to the actual settling condition, thereby improving the settling efficiency and effect.

The invention discloses a crystal elutriation leg system and a crystal elutriation process. The crystal elutriation leg system comprises an elutriation water distribution section, a crystal mush elutriation discharging section and an elutriation settling separation section which are connected in sequence. And the elutriation water distribution section is provided with a distribution disc with special pore diameter distribution, so that elutriation water is uniformly distributed. The ascending velocity of elutriation water is designed to be larger than the maximum free settling velocity of crystals, so that the distribution disc is prevented from being blocked. In the elutriation settling separation section, the upward flow velocity of clear liquid is controlled to be smaller than the minimum free settling velocity of crystals, so that fine crystals and impurity mother liquor are elutriated, replaced and floated, and target large-particle crystals are settled and enriched in the discharging section. Through cooperative control of the three-section type structure and the key flow velocity, mother liquor impurity entrainment in a crystal product is greatly reduced, the crystal purity and granularity uniformity are improved, and the device is suitable for various crystal separation and purification systems with the solid density larger than the liquid density and has the advantages of being scientific in design, low in cost and high in automation degree.

A fluid product dispensing device comprising a metering valve mounted on a reservoir (1) containing at least one active ingredient suspended in a pressurized propellant gas having a liquid density at 21°C less than or equal to 1.20 g / cm3, said metering valve comprising a valve body (10) containing a metering chamber (20), and a valve (30) sliding axially in said valve body (10) between a rest position and a dispensing position, to dispense the contents of said metering chamber (20), said metering chamber (20) being, in the rest position of the valve (30), substantially isolated from said reservoir (1), said valve body (10) comprising at least one fluid passage opening (11), said metering valve defining a sedimentation volume V disposed below said at least one passage opening (11) in the inverted operating position, with said metering chamber (20) disposed below said reservoir (1),said sedimentation volume V being greater than or equal to 500 mm3 and less than or equal to 1000 mm3. "Figure for the abbreviation: Figure 2",