Gravimetric method and device for measurement of moist content in moisture-containing organic material, particularly, in timber
FIELD: measurement engineering.
SUBSTANCE: moisture is extracted from moisture-containing organic material, for example, from timber. Device is used which has pressure-tight chambers for removing moisture, carriages for loading organic materials, moisture collectors and heat lines. Weight of removed moisture in relation to weight of organic material is calculated.
EFFECT: reduced time of procedure; increased precision of testing.
3 cl, 5 dwg
The invention relates to the field of determining moisture content and other thermally extractable substances in organic materials having a capillary structure, including wood, including materials of synthetic origin.
Known indirect methods for determining moisture content in organic materials and sell their devices, based on the measurement of parameters that depend on moisture content, such as conductivity, dielectric constant, etc. the Main disadvantage of indirect methods is the need for prior calibration of measurement systems for each type of the investigated material with the use of direct methods for the determination of moisture content.
To well-known direct methods of determining moisture content are dried at 105°C to constant mass, distillation of water with a nonpolar organic solvent, subtitling reagent Fisher (G. Kononov. Chemistry of wood and its main components. - M.: 1999, 247 S.), of which the most common and close in fact present invention is a standard drying method according to GOST 11014-81 (with subsequent amendments). This method is repeated determination of the mass of the test sample moisture-containing material in the drying process when the temperature is 105° C. drying and weighing continue up until the mass of the sampled material will not cease to decrease. The resulting drying substance is considered "absolutely dry", and relative (WREL) or absolute (Wabs) the moisture content of the source material in a percentage determined by the formula
where mW- initial sample mass of material, mabsthe mass of absolutely dry substance obtained from the initial sample of the material in the drying at a temperature of about 105°to stabilize the mass.
The most significant disadvantage of the standard method is that the drying process at a temperature of 105°and multiple weighing samples long. In addition, the accuracy of determination of moisture by this method is low because not all the moisture held in the capillaries of the plant tissue may be removed at the same temperature drying. The selection of bound moisture from organic material in significant (up to 300...400° (C) increase in temperature would lead to the fact that due to thermal degradation of the organic matter together with the moisture of the solids are removed and degradation products.
The aim of the invention is the reduction product is littelest procedures for determining the amount of moisture, contained in the organic materials of plant origin and increase the accuracy of determining the amount of moisture due to its more complete separation from the studied material, as well as the opportunity to determine the content of different types of moisture released from the studied organic material at different temperatures.
This technical result is achieved by the gravimetric method of determining the moisture content of the sample crushed investigated moisture-containing organic material is quickly heated to a temperature in the range of 105...375°over time, which in the studied organic matter do not have time to occur chemical processes, in particular with the participation of the contained moisture by thermal contact with the heated surface of the heat transfer material in concurrent mechanical pressure is applied to this surface. Selection and determination of the mass of moisture removed from the organic material at different temperatures, are produced at different temperatures a few cameras. After determining the mass of extracted moisture carry out an analysis of its composition.
The invention is disclosed using figure 1-5. Figure 1 presents the design of a device for separating moisture from one sample alternately in multiple to the measures and figure 2 shows a device for separating moisture out of several sub-samples of organic material. Figure 3-5 shows the three main phases of operation of the device separating moisture for one camera Department moisture on the proposed method of determination of its content in organic material.
The device in figure 1 includes several sealed chambers remove moisture 1 (the number of chambers of moisture removal is determined by the amount of moisture content, the content of which you want to analyze), boot the carriage 2 with the cavity 3 bounded from below by a thin partition 4 from a material with high thermal conductivity, and a few (by number of cameras remove moisture) drives moisture 6. Each of the drives moisture 6 communicates with one of the chambers of moisture removal 1. To ensure the collection of moisture released from the organic matter, the drive moisture 6 is equipped with a refrigerator and / or regenerated adsorption element 7, and may simultaneously be working chamber chromatograph. To prevent condensation from moisture in the walls of the chamber to remove moisture and drive their heated by the heater 14. The device operates as follows.
A portion of the crushed moisture-containing organic material 5, the mass of which is taken for mWplaced in the cavity 3 of the carriage 2. Then slide the RAM is moved into the first chamber to remove moisture where at the temperature T1 is separated moisture, temperature extraction from organic matter less than or equal to T1. After that, the carriage with the sample is transferred into the second chamber to remove moisture and released from the sample moisture is completely distilled to drive moisture 6 which is connected with the first chamber to remove moisture and weighed; the weight of this moisture is taken for mWW1. In the second chamber to remove moisture sample is heated at a temperature T2 and produce the removal of her moisture, temperature selection, which lies in the range T1...T2, after which the carriage with the sample moved into the next chamber to remove moisture and released from the sample in the second chamber to remove moisture in distilled communicated with her drive moisture and weighed; the weight of this moisture is taken for mWW2. The above procedure for removal, distillation and weighing moisture repeat for all cameras remove moisture at temperatures, respectively, T1, T2, ...Tn, where T1<T2<T3<...<Tn, T1=105°S, Tn≤375°C. the Mass of moisture removed from the organic material at temperatures T1, T2, ...Tn-1, take mWW1, mWW1, ...mWWnrespectively. Then, determine the mass of a sample after separation from it of moisture in the last chamber at the temperature Tn, take it for mabs. Then calculate the relative (WkREL) or absolute (Wkabs) the content is of different types of moisture, released at the temperature Tk by formulas
where k is a positive integer and 1<k<n.
After weighing the moisture released from the organic material at different temperatures, produce chromatographic or other analysis of its composition.
The device in figure 2, is designed to separate the moisture on the "parallel" scheme, includes several sealed chambers remove moisture 1 (the number of chambers of moisture removal is determined by the amount of moisture content, the content of which you want to analyze), and the same number of boot carriage 2 with the cavity 3 bounded from below by a thin partition 4 from a material with high thermal conductivity. The device operates as follows.
First, cook N (the number of types of moisture content which you want to analyze) hanging investigated chopped moisture-containing organic material 5. A lot of the first, second, etc. hanging accept, respectively, for mW1, ..., mW2, ..., mWk, ..., mWn. Each of the hanging moisture-containing organic material is placed in one of the boot of the carriage 2, then each carriage 2 is introduced into one of the chambers of moisture removal 1. Each of the cells 1 to produce the removal of moisture from placed in her sample of organic the ski material at a temperature T1, T2, ..., Tk ... or Tk, where T1<T2<T3<...<Tn, T1=105°S, Tn≤375°C. After removal of moisture from hanging the moisture-containing organic material they weighed again and take their mass, respectively: mWM1, mWM2...mWMk, ...mWMn. Then calculate the relative (WkREL) or absolute (Wkabscontents of various types of moisture released during the temperature Tk by the formulas:
where k is a positive integer and 1<k<N.
Figure 3-5 shows three stages in the process of removing moisture in one of the cells 1. The camera 1 includes the heat pipes 8 and 11 with the heating elements 9. In the lower part of the upper heat pipe 8, provided with the clamping device 13, there is a system of channels 10 for withdrawal of moisture vapour from the lower surface of the heat pipe 12 into the internal cavity of the chamber 1. Figure 3 shows the initial phase of the process of moisture removal, when the cavity 3 of the boot of the carriage 2 is located outside of the gap between the heat pipes 8 and 11, the temperature of which is maintained constant and equal to the desired value Tk in the range of 105...375°C. Hitch 5 investigated slurry of organic material placed in the cavity 3 of the boot of the carriage 2. Then boot the carriage side quickly move in a horizontal plane so that it Polo is th 3 was between the working surfaces 12 of the heat pipes 8 and 11, as shown in figure 4. After that, the upper heat 8 quickly lowered and with the help of the clamping device 13 is tightly compress the portion 5 of the investigated material with thermally conductive wall 4 between heated to the required temperature of the working surface 12 of the heat pipes 8 and 11. This phase of the process is presented in figure 5. Due to constant thermal contact and mechanical pressure applied perpendicular to the surface of contact of organic material with heat pipes, carry out rapid heating of the entire volume of the sample to the desired temperature Tk for the time (less than 1), which does not occur chemical modification of the investigated organic material. The process of moisture removal is in the nature of "microexplosion", in which there is intensive emission of moisture from the amount of organic material, as it formed a closed microregions, filled with pairs of boiling moisture, which due to internal pressure to break through the layer of organic material on its surface. The channel system 10 of the upper heat pipe provides a more rapid withdrawal of moisture from the heating zone into the internal cavity of the camera 1.
After the moisture to be removed at a given temperature Tk, will be displayed in the internal cavity of the chamber 1, the upper heat pipe 9 is raised, and loading the loading carriage 2 with organic material is displayed and the camera 1.
To ensure rapid and uniform heating of the sample moisture-containing organic material to its initial (before you put it in the camera 1) mass mWkmust meet at least one of the two following conditions:
where M is the total mass of the heat pipes 8 and 11,
cmand cm- specific heat capacity, respectively, of the investigated material and the material of the heat,
mWWkis the mass of the moisture released from the sample mWkin the chamber to remove moisture at a temperature Tk,
λk- heat of vaporization at temperature Tk,
k - coefficient of heat losses in heat transfer through
the heat pipes 8 and 11 and the partition wall 4 to the hinge of the studied material;
2) the power of the heaters 9 should be sufficient to maintain a constant heat flux, providing heating of the sample to the desired temperature Tk in the range of 105...375°for the time at which the removal of moisture is in the nature of "microexplosion" (<1). For the limiting case, when the relative humidity of organic material is close to 100%, and at temperatures below the critical temperature of water (about 374°C)the flow of heat to the sample of organic material must be above 4 kW per one gram sample of organic material.
1. Gravimetricheskie determine the moisture content in the moisture-containing organic material, in particular in the wood, by calculating the ratio of the mass of moisture to the mass of organic material, characterized in that the extraction of moisture from the at least one hinge moisture-containing organic material and determining the moisture content of exercise due to thermal contact with the heat pipes in several chambers of moisture removal at different temperatures in the range 105...375°by heating the moisture-containing organic material over time, which does not occur chemical modification of organic material, simultaneously exerting mechanical pressure on the moisture-containing organic material perpendicular to the surface of its contact with the heat pipes, the heat flow energy to the sample moisture-containing organic material should be not less than 4 kW per gram of sample released moisture is collected in separate enclosures are equipped with refrigerators or sorption elements weighed.
2. Device for collecting moisture in the determination of the moisture content in the moisture-containing organic material, in particular wood, containing a sealed chamber to remove moisture and installed in her carriage to load the moisture-containing organic material, characterized in that it further comprises a sealed chamber removed what I moisture, which number corresponds to the number of drives moisture, equipped with a fridge or sorption element, each airtight chamber to remove moisture contains two located one above the other of the heat from a material with high thermal conductivity, equipped with heaters with a total capacity of not less than 4 kW per gram of the investigated aqueous organic material, and lower the heat fixed, and the upper heat pipe having in the lower part of the channel system for the pair, can move reciprocating in a vertical plane and provided with a clamping device for maintaining constant thermal contact between the heat pipes with moisture-containing organic material, and the number of carriages moving in the horizontal plane corresponds to the number of cameras remove moisture.
FIELD: atomic power engineering; registration systems of leaks of the heating carrier of the 1-st loops of the reactor facilities of nuclear electric power plants.
SUBSTANCE: the invention is pertaining to the field of atomic power engineering and may be used in at the reactor installations with the water-to-water and water-graphite reactors, in particular, at a decompression of the 1-st loop. The registration system of leaks of the heating carrier of the 1-st loops of the reactor facilities of a nuclear electric power plant contains a block of the controlled rooms with equipment of the 1-st loop of the reactor installation connected through air ducts of exhaust ventilation with a block of the channels intended for measuring of relative humidity of the air in the controlled rooms, that includes a reference channel intended for measuring of relative humidity of outdoor air in the rooms with the measuring channels. Sensor units of measuring channels are connected to a control unit for recording and matching of the parameters of the relative humidity of the air in the controlled rooms and in the room with the measuring channels, each of which is made in the form of an expander, on one butt of which there is a branch pipe with a filtering tool connected with the air duct, and on the other butt there is a flange intended for mounting of a sensor. At that outside of the expander there is a cooling chamber. The invention allows to simplify the process of the control over the indications of the relative humidity of the air in the controlled rooms and to improve reliability of operation of the reactor installation by well-timed detection of a location and intensity of the leakage of the heating carrier.
EFFECT: the invention ensure simplified control over the indications of the relative humidity of the air in the controlled rooms, improved reliability of the reactor installation operation by well-timed detection of a location and intensity of the heating carrier leakage.
6 cl, 9 dwg
FIELD: hygrometers with bolometric heat sensitive member, stove or furnace using such hygrometer and method for controlling stove or furnace.
SUBSTANCE: hygrometer includes two static bolometric heat sensitive members for accurate detection of humidity value. Stove or furnace includes bolometric hygrometer secured to one side of bracket in air discharge opening for deflecting direction of air flow in order to detect humidity value at high accuracy in cooking chamber. Method for controlling operation mode of stove or furnace provides different periods of heat treatment of food products in package or without it.
EFFECT: enhanced accuracy of humidity measuring.
13 cl, 15 dwg
FIELD: measurement technology.
SUBSTANCE: electric insulating base, electric insulating substrate onto which moisture-sensitive coating is applied on the base of gelatin which has its external layer tanned, two plated electrodes which have contact surface to contact with moisture-sensitive coating on base of gelatin and measuring device connected to outputs of plated electrodes. Two clamping units are introduced into the device additionally. Any clamping unit intends for creating permanent pressure of corresponding plated electrode onto working surface of moisture-sensitive coating on base of gelatin. Layer of gelatin coating has uniform thickness. Contact surface of plated electrodes adjacent the moisture-sensitive gelatin-based coating is made to be oxidized and flat.
EFFECT: prolonged service life; higher stability of operation; increased moisture resistance.
5 cl, 1 dwg
FIELD: agricultural engineering.
SUBSTANCE: drier has heat supply channel with heat generator connected thereto, said channel consisting of sequentially connected modules, and containers with perforated bottoms positioned on modules and tightly adhering thereto. Planar adjusting valve disposed within each module consists of two parts interconnected through cylindrical pivot hinge. One of parts is immovably attached to upper module carcass end rib maximally distant from module heat carrier inlet and to its side walls in downwardly inclined position toward heat carrier flow delivered therein. Other part of valve is shorter than said one part and is connected with lever-arm arranged at the outside of module.
EFFECT: increased efficiency by providing smooth, easy and adjustable feeding of heat carrier to container bottom and performing simultaneous drying of various crops or single crop having different moisture content by removing containers with dried heap and replacing them with newly fed containers without switching off of heat generator.
8 cl, 2 dwg
FIELD: the invention refers to the field of water extraction technologies out of drying materials and may be used in different branches of industry such as wood-manufacturing, chemical, biological, pharmaceutical, textile and also in agriculture.
SUBSTANCE: in the mode of drying materials with the aid of thermal, acoustic and convective impacting on drying material is heated air is supplied into the chamber of the sound source and acoustic field and convective flow directed in a common acoustic duct are simultaneously made in it. The flow is given into each drying chamber separately or into all simultaneously before receiving given moisture of material. An average convective speed of the air for all drying chambers for example for gas-dynamic generator is defined according to a calculating formula. The arrangement has several drying chambers located in the flatness of the chamber of sound source in radial direction relatively to its vertical axle and forming with it a common acoustic duct. The chambers are prolongation of common acoustic duct and are provided at the entrance with dampers for possibility of alternate or simultaneous impacting of air flow on material, and at the exit- openings.
EFFECT: the invention must provide increasing effectiveness of using acoustic energy.
3 cl, 2 dwg
FIELD: heat engineering, in particular, methods for control of heat condition of aerodynamic heating installations, applicable in installations for drying of long-sized products.
SUBSTANCE: the method consists in heat-up of the space of the working space to the preset temperature and upkeep of it within the preset range during the preset time by supplying electric current to the electric motor of the rotor heater, rotation of the impeller of the rotor heater an increasing of the speed of its rotation with adjustment of the consumption of heated gas heat-transfer agent fed to the working passage due to variation of the speed of motion of the gas heat-transfer agent, the speed of motion of the heat-transfer agent is varied by variation of the frequency of the electric motor supply voltage, in the stage of heat-up the frequency of the electric motor supply voltage is increased so that the value of the electric motor current would remain constant and equal to the preset value, and in the stage of temperature upkeep within the preset range the requirement of current constancy is neglected, and the voltage frequency is varied within the fixed range.
EFFECT: reduced time of warm-up of the working space.
FIELD: machines or apparatus for drying solid materials by removing water from the materials.
SUBSTANCE: press-dryer comprises sealed vacuum chamber composed of two semi-housings connected by flexible connection means along perimeters thereof. Two cavities for limber receiving are defined inside the chamber. Axis of chamber rotation extends between the cavities and is directed along longitudinal limber axes. The chamber is provided with retainer to fix angular chamber position in vertical plane. The cavities may be alternately arranged from above and from below of above axis of chamber rotation. Space is created between inner surfaces of semi-housings and the cavities. Gas-permeable and heat-conductive filler is arranged inside the chamber so that the space is fully filled with the filler. The chamber has heating means to heat the filler and semi-housings, vacuum pump to evacuate chamber interior and air supply means. The press-dryer also comprises releasing means to disconnect semi-housings one from another.
EFFECT: increased quality of limber heating.
7 cl, 1 dwg
FIELD: SHF drying f woods.
SUBSTANCE: packages of woods are put into cassette with longitudinal recesses in side walls through which recesses the packages are treated with HF energy pulse flux. Inside the flux the packs of woods are formed on top branch of transporter. The pack is introduced into cassette and the pack is treated from its middle to its ends with SHF pulses during three steps. During first step the packs are warmed till 35-65°, during the second step - till 60-90° and during third step - till 75-105°. Circulation of vapor-air mixture is carried out which mixtures washes warmed packs about and after it the mixture is sucked away. Device for SHF-drying of woods has frame onto which cassette with woods is mounted. Longitudinal recesses of the cassette join magnetrons. Cassette is made in form of side, lower and top walls limiting its volume. Cassette's ends are closed with shutters. Any magnetron is provided with fan for supplying air into chamber for washing woods' packs about.
EFFECT: improved quality of drying.
6 cl, 3 dwg
FIELD: drying solid materials.
SUBSTANCE: method comprises evacuating volume up to 2·10-3 mm Hg, supplying dry air with simultaneous evacuation up to the pre-break down pressure, and switching on the microwave heating. During drying, the pressure inside the chamber is controlled thus providing continuous evacuation. The device comprises drying chamber made of the multi-mode resonator. The side of the resonator opposite to the microwave bus is provided with vacuum-tight detachable flange with the lid. The resonator receives pads arranged in rows and made of radioparent material the height of the side of which is equal to the double depth of penetration of the microwave energy at its working frequency for given material and initial humidity. The distance between the pads does not exceed 0.1 of the microwave wavelength for maximum coefficient of charging of the resonator which is connected with the vacuum system.
EFFECT: enhanced efficiency of drying.
2 cl, 1 dwg
FIELD: equipment of food industry in production of frozen food products.
SUBSTANCE: in the extrusion vacuum-freeze ultra-high frequency freeze dryer including a freeze chamber with sources of super-high frequency energy, device in the form of an extruder for delivery of the product in it, adapter in the form of the Laval nozzle for production of a steam gate, divider device installed directly after the zone of action of the sources of super-high frequency energy, remote desublimator and a locking gate for unloading of the ready-made product from the installation, the novelty is in the fact that rollers-stackers are placed under the adapter on the horizontal apron conveyer made of radiotransparent material positioned above which in the direction of its motion are the main waveguide with the high-velocity waveguides at the input and output, consisting of separate perforated sections with own independent sources of super-high frequency energy and dielectric lenses, line for connection of absorbing matched load and rollers.
EFFECT: enhanced accuracy of control of the process parameter, reduced loss of power and enhanced reliability of the installation.
FIELD: devices for drying grains.
SUBSTANCE: device can be also used for drying loose materials. Rectangular-shaped drier for loose materials is provided with supply of heat carrier disposed under layer of material performed through false bottom and with output disposed above layer of material. Dry material is unloaded from drying area to bunker by means of frame provided with raking up battens, which frame reciprocates at adjusted frequency between two horizontal rows of perforated U-shaped profiles which form false bottom. Drier also has loading unit and conveyer (or cellular wheel) for unloading dry material out of bunker.
EFFECT: improved quality of drying; précised adjustment of unloaded material.
2 cl, 3 dwg
FIELD: drying solid materials.
SUBSTANCE: vacuum press-dryer comprises pressure-tight chamber which is defined by the housing and lid interconnected over the periphery of the butt, heating stoves for heating and pressing boards and limbers mounted inside the chamber, vacuum pump connected with the space of the vacuum chamber, and water vapor condenser. Between the stoves is a space for receiving boards and limbers. The top stove is connected with the lid, and the bottom stove is connected with the housing. The top stove has bearing plate connected with the lid and heated sections interposed between the bearing plate and the space for arranging one layer of boards and limbers. The heated sections are flexibly connected with the bearing plate. The lateral sizes of the heated sections are equal to these of the boards and limbers.
EFFECT: reduced power consumption and improved quality of drying.
4 cl, 2 dwg
FIELD: the invention refers to wood working particularly to constructions of vacuum installations for drying carving wood.
SUBSTANCE: the installation has along the length of a drying chamber a row formed by ventilators, heaters and airways mounted on the external side of the chambers. At that airways are connected for each sections separately. The distribution of the priming flow of direct steam and hot-air mixture is made out of a number of distributors between ventilators and heaters and directly in the drying chamber along the side walls in several tiers. The installation must provide even effective blowing , heating of carving wood with direct steam and formed saturated hot-air mixture of wood's liquid according to the height and the length of a stack of carving wood or tree-trunks without forming in them zones that were not heated and blown.
EFFECT: contributes to receiving of quality dried carving wood without forming cracks and hogs.
3 cl,3 dwg
FIELD: building materials production.
SUBSTANCE: invention relates to production of ceramic brick. Proposed method of green brick drying includes delivery of heat carrier, for instance, hot air into chamber opposite to object of drying and removal of used heat carrier, and also recirculation of used heat carrier into definite zone of chamber or into mixing chamber and delivery of steam to heat carrier to regulate pressure of steam in heat carrier. Green brick drying device contains chamber with inlet and outlet doors, cars moving along chamber, heat carrier delivery and removal channels with gates and recirculation channel and mixing chamber. Channel is provided to delivery steam with control shutoff valve. Said channel can be laid both to heat carrier delivery channel and to mixing chamber to control steam pressure in heat carrier.
EFFECT: prevention of brick cracking in drying.
3 cl, 1 dwg