Combined feeder and mixing
(57) Abstract:The invention relates to the combined feeder and mixing for introducing the first fluid into gas and sent in the channel flow in the direction of flow of the second fluid medium and for mixing fluid. The device comprises at least one pipe, directing the first fluid environment. The pipe includes at least one feed opening and the mixing box located after the feed holes relative to the direction of flow. The mixing insert contains mixing elements, which are relatively small in comparison with the hydraulic diameter dhydrchannel flow. The mixing elements are arranged parallel to each other in rows in a plane which is angled to the flow direction. Mixing elements of each row are inclined relative to the plane in the same direction relative to each other and in the opposite direction relative to each adjacent row. In the calculation of the cross-sectional area and hydraulic diameter dhydrchannel flow provided by 0.05 to 10 feed holes per square meter of area of the cross is well, between 0.05 and 3 dhydr. The invention provides for introducing the first fluid into the second fluid medium at low pressure loss and low costs of equipment and commissioning, as well as homogeneous throughout the cross section of the channel current distribution of the first fluid. 7 C.p. f-crystals, 4 Il. The invention relates to the combined feeder and mixing for introducing the first fluid into gas and sent in the channel flow in the direction of flow of the second fluid medium and for mixing the fluid with at least one first guide the fluid pipe with at least one feed opening and located relative to the direction of flow after the feed openings to the mixing box, and in the calculation of the cross-sectional area A and the hydraulic diameter dhydr.channel flow provided by 0.05 to 10 feed holes on m2cross-sectional area and the distance between the feed orifice and the mixing insert is a value between 0.05 and 3 dhydr..Such a combined feeder and mixing follows from FR 2341040 A1.In many industrial applications trebuet asnau the flow of the substance to achieve high efficiency of the process. So, for example, catalytic reduction contained in the exhaust or flue gas nitrogen oxides by the method of selective catalytic reduction (SCR) requires the addition of a reducing agent in gaseous form to be cleaned from the nitrogen to the flow of exhaust or flue gas, namely before the catalytic Converter. As the reducing agent is usually in the flue gas inject the ammonia-air mixture, and the dosing flow rate of the ammonia-air mixture in comparison with the flow of exhaust or flue gas is very small. This dosing flow rate of the ammonia-air mixture is usually about 2 to 5 volume percent of the exhaust or flue gas.So you can choose the desired removal of nitrogen amount of the catalyst may small, strive for uniform use of the catalyst throughout the cross section of the channel of the exhaust gas. This fact makes it necessary to inject the ammonia-air mixture may uniformly throughout the cross section of the channel of the exhaust gas and mixed with the exhaust gas.Even adding a relatively small flow of liquid or gas to a relatively large flow Slonim from the point of view of hydrodynamics and therefore technically associated with very high costs. Currently, this problem is solved due to the fact that in the channel of the exhaust gas post many separately controlled injection pipes with multiple nozzles, to obtain uniform distribution of the nozzles over the entire cross section of the channel of the exhaust gas and thus places the entrance of the ammonia-air mixture in the flue gas. The disadvantage of this solution is due to introducing pipe pressure loss in the flue gas. In addition, this solution requires a very high cost of equipment, relatively piping, nozzles, control valves and control or regulation of dosing. In addition, adjustment of such a system when commissioning is very tense from the point of view of time and expense.The basis of the invention therefore have the task of creating a device with which at negligible pressure loss, low costs of equipment, as well as with low costs of commissioning is achieved by introducing the first fluid into the second fluid environment and homogeneous throughout the cross section of the channel current distribution of the first fluid.This task in the combined feeder and mixing for wwe environment and for mixing the fluid, containing at least one first guide the fluid pipe with at least one feed opening and located after the feed holes relative to the direction of flow of the mixing insert, according to the invention is solved in that the mixing insert contains mixing elements, which are relatively small in comparison with the hydraulic diameter dhydr.channel flow and are parallel to each other in rows in a plane which is angled to the flow direction, while mixing elements of each row are inclined relative to the plane in the same direction relative to each adjacent row, and in the calculation of the cross-sectional area A and the hydraulic diameter dhydr.provided of 0.05-10 feed holes per square meter of cross-sectional area of channel flow, and the distance between the feed holes and the mixing insert is the largest, consisting of between 0.05 and 3 dhydr.the hydraulic diameter.The hydraulic diameter is thus defined as four times the cross-sectional area of A channel flow divided by its perimeter.Tselesoobrazen">Preferably, if the distance between the feed orifice and the mixing insert is 0.1-1 hydraulic diameter.May provide 0.05 to 5 tubes per square meter of cross-sectional area of the channel flow.This is the preferred placement of 0.1-1 pipe per square meter of cross-sectional area of the channel flow.In the direction of flow of the second fluid before the feed holes and the mixing insert is provided by means of flow direction.Such funds flow direction are, for example, shields, etc.The mixing insert contains 0.5-50 mixing elements per square meter of cross-sectional area of the channel flow.It is expedient to provide at least one insert to separate the channel flow at the partial channels, and in each partial channel provides one input hole and one of the mixing box.Particularly preferred use of the claimed combined feeder and mixing is the introduction of gaseous ammonia, for example, ammonia-air mixture, containing nitric oxide gas see the truck, and the mixing of ammonia and containing nitric oxide gas mixture. An alternative to the ammonia-air mixture in principle, be any form of ammonia substance, in particular an aqueous urea solution.Examples of carrying out the invention are explained in more detail using the drawings on which is shown:
Fig.1 - basic system for injection, and simultaneously, a uniform distribution of ammonia in the flue gas;
Fig. 2 - corresponding to the invention combined feeder and mixing for the introduction of ammonia into the flue gas directed into the flue gas;
Fig.3 - the location of the combined feeder and mixing according to figure 2 in the pipeline flue gas fossil fuel 600-megawatt power plant; and
Fig. 4 is another corresponding to the invention combined feeder and mixing with the paste for separation channel flow.In Fig. 1 - 4 - identical parts have the same reference position.Fig. 1 shows in top view in cross-section of the flue gas channel or a 4 channel conventional system 2 for the introduction of ammonia into the current here is perpendicular to plosone evenly distributed in the flue gas 4 and have as feeding holes nozzle heads 8. Injection pipe 6 on the input side are connected each through an adjustable valve 10 with a supply line 12 for the ammonia-air mixture.Due to the many located in the flue gas 4 injection pipe 6 is called the head loss, which cannot be neglected, which, for example, degrades the electrical power of the power plant. In addition, the costs of equipment are very high. They can be, for example, for a 600-megawatt power plant to approximately 30 - 50 injection tubes 6, each with an adjustable valve 10 and the number of nozzles of the order of 1600 nozzle heads 8. For commissioning and maintenance of such system 2 requires high costs in time and other expenses.In Fig.2 shows the corresponding invention combined feeder and mixing 14. As presented here above you can see eight respectively provided with each control valve 16 of the injection pipe 18, which on the input side is connected to the inlet piping 20 for the ammonia-air mixture M1, and on the output side into provided as the feed holes of the nozzle head 22.For Neporozhniy, conventional injection system 2 identified known from Fig.1 channel currents 4. In the exemplary embodiment the cross-section A of this channel flow 4 is about 8 m2what if specified here, the cross-sectional shape 2 x 4 m, we get hydraulic diameter of the order to 2.67 m Hydraulic diameter dhydr.when this is defined as four times the cross-sectional area A divided by the perimeter of the U channel flow 4.In the graphical representation after the nozzle heads 22 are arranged in a staggered manner in two rows of eight mixing elements 24a - 24h. These are related to the mixing box 26 of the mixing elements 24a - 24h are keystone shape and inclined downwards out of the plane of the image according to the narrow edge of the trapezoid. The angle of inclination relative to the image plane could be between 10 and 60opreferably between 30 and 45o. Sent in the channel flow 4 fluid preferably flows when it is perpendicular to the image plane, namely entering the image plane from the top down. Using these mixing elements 24a-24h are achieved as local turbulence of the fluid with the introduction of Teco mixing. For uniform distribution introduced in introduced in the fluid ammonia-air mixture throughout the cross section of the channel flow 4 is advantageous if it is provided 0,5-50 mixing elements 24 on m2cross section of the channel flow, preferably this amount is between 0.5 and 10 mixing elements on m2.For schematically shown in Fig.3 the cut pipe flue gas 4 is not presented here in more detail fossil fuel power plants combined feeder and mixing 14 according to Fig. 2 is located in the direction of flow of the existing fluid medium M2, namely containing nitrogen oxide flue gas 28, between the steam generator 30 and DeNOxreactor 32.When working power plant containing nitrogen oxide flue gas 28 from the steam generator 30 through located in the flue gas guide flow flaps 34 flows to the combined feeder and mixing 14. Directing the flow plates 34 serve to homogenize the velocity profile of the flue gas 28, so that the flue gas 28 is almost equal velocity throughout the cross section of the flue gas 4 to the new gas 28, entered the order of 2 to 5 volume percent directed to the inlet pipe 20 and metered by a valve 16 of the ammonia-air mixture M1. Located in the stream of flue gas 28 after the feed pipe 18 of the mixing insert 26 is achieved by mixing the ammonia-air mixture from the flue gas 28, so that by DeNOxthe reactor 32 is supplied uniformly mixed with ammonia flue gas 28'.On located in DeNOxthe reactor 32 planes one above the other catalysts 34a - 34e, the so-called DeNOx-rolled - jams contained in the flue gas 28' nitrogen oxides with ammonia catalytically converted by bringing into contact the catalysts 34a - 34e into nitrogen and water. DeNOxreactor 32 so leaves free from nitrogen oxides and ammonia flue gas 28". Due to uniform distribution of ammonia in the flue gas 28 catalysts 34a - 34e are used uniformly throughout the cross section.The distance a mixing insert 26 from the feed pipe 18 should, in General, to lie between 0.05 and 3 dhydr.. Preferably this distance a is between 0.1-1 dhydr..Fig. 4 shows another example implementation of a combined feeder and mixing 36. C is s 18, the supply line 20 for the ammonia-air mixture M1 and nozzle head 22. Additionally, the insert 38, which divides the channel flow 4 for a length of about 3 dhydr.eight partial channels 4a - 4h. In addition, each partial channel 4a - 4h given in compliance provided as a feed hole jet head 22 and in principle the same design, but reduced compared to Fig.2 mixing insert 26a - 26h. Each of these mixing inserts 26a - 26h covers 24 arranged in rows in staggered keystone mixing elements 24'. For clarity, the mixing elements 24' are shown only in the mixing insert 26a. It goes without saying that also other mixing insert 26b - 26h have the same number and configuration of the mixing elements 24', as the mixing insert 26a.With the help provided here insert 38 is possible more complete and intensive mixing entered here the ammonia-air mixture M1 is sent in the channel flow 4 fluid medium M2, for example, containing nitrogen oxide flue gas 28 according to Fig.3. Alignment concentration in the large space of possible existing NOx- NH
FIELD: method for producing gas mixtures for testing gas analyzers.
SUBSTANCE: method for producing checking gas mixtures includes desorption of dosed component from adsorbent into carrier gas flow, let at excessive pressure through a vessel filled with adsorbent, wherein preliminarily adsorbed under excessive pressure is a given amount of dosed component. Further, carrier gas flow is let through turbulent throttle mounted serially with vessel, forming at outlet of device the starting flow of checking gas mixture with maximal concentration of component for current filling of adsorbent and gas-carrier pressure set in the vessel. Concentration of component in the flow of checking gas mixture at device outlet is controlled by changing pressure of carrier gas in the vessel and diluting starting flow of checking gas mixture by flow of carrier gas from the source of compressed gas, let through alternating turbulent throttle connected in parallel to vessel and first throttle. Both throttles operate in above-critical mode of gas stream ejection.
EFFECT: possible production of checking gas mixtures with continuous row of values of concentration of dosed component in broad range.
2 cl, 1 dwg
FIELD: methods for preparing steam-gas mixtures of substances in mass concentration units, possible use for metrological provision (attestation, verification and graduation) of gas analyzers.
SUBSTANCE: in the method for preparation of steam-gas mixture for calibrating gas-analyzers in mass units of concentration of the component being analyzed, comprising injection of given amount of the component being analyzed into preliminarily vacuumized hermetic vessel, mixing thereof with diluting gas and forcing resulting mixture towards the gas analyzer being calibrated, a bottle of known capacity is connected to hermetic vessel with possible isolation from it, which bottle is preliminarily vacuumized and its mass is measured, value of pressure is computed, which ensures achievement of given mass concentration of the component being analyzed at a temperature which equals environment temperature in accordance to the formula: where Pn - pressure, ensuring achievement of given mass concentration of the component being analyzed, kPa; - given mass concentration of the component being analyzed, g/m; T - environment temperature, °K; M - molecular mass of the component being analyzed; K - coefficient, which includes the universal gas constant and a numeric value which leads to required dimension of pressure (K=8,3·10-3m3·kPa/°K·grammolecule), resulting combined volume of vessel and bottle is vacuumized, component being analyzed is injected into it until achievement of computed pressure at temperature which equals temperature of environment, after that the bottle is isolated and disconnected from hermetic vessel, bottle mass is measured and effective value of mass concentration CM is derived from formula where CM - mass concentration of the substance being analyzed, g/m3; Mk - mass of bottle with the substance being analyzed, g; M0 - mass of vacuumized bottle, g; V - bottle capacity, m3.
EFFECT: increased precision of preparation of steam-gas mixture in mass units of substance concentration during calibration of gas analyzers, expanded range of concentrations of mixture components.
FIELD: quantum electronics; supersonic gas-mixing lasers including gas-dynamic and chemical lasers.
SUBSTANCE: proposed method includes supply of energy-carrying gas to supersonic nozzle and injection of radiating gas in the form of supersonic wakes into supersonic region of nozzle. Outer surfaces of wakes are screwed. Proposed device for mixing gases within supersonic laser has supersonic nozzle and injector connected to energy-carrying and radiating-gas sources, respectively. Injection holes receive pipes whose outlet openings are uniformly disposed on cross-section of nozzle supersonic region and are arranged along nozzle longitudinal axis. Outlet ends of injector pipes are made in the form of screw-shaped lugs disposed along outer surface of wakes being injected. Lugs can be made in the form of separate headpieces mounted on outlet ends of injector pipes.
EFFECT: enhanced efficiency of transferring laser energy stored by energy-carrying and radiating gas molecules which enhances laser efficiency.
2 cl, 4 dwg
FIELD: process engineering.
SUBSTANCE: invention relates to gas industry and may be used for feeding odorant into gas flow to add to safety of gas transport in pipeline. Proposed method consists in gas bubbling, determination of thermobaric parametres in bubbling process, and determination of quantitative properties of gas saturation by odorant vapors. Depending upon obtained data and measured current gas flow arte in the main pipeline, ACS computes required amount of odorised gas and inputs its into pipeline gas. Proposed device comprises liquid odorant tank, babbling tank, ACS comprising transducers bubbling thermobaric parametres, gas counter to determined has flow rate after bubbling and control unit to process received data and generate control signals to odorisation process control elements. Gas analyser and temperature controller may be incorporated with proposed device.
EFFECT: expanded range of odorised gas, possibility to be used in low-capacity gas pipelines.
4 cl, 3 dwg