Six-section solvent for the preparation of sugar syrup.
The solvent (fig. 7) is the main apparatus of the syringe station SSC (the diagram and description of the station see below). It consists of a 3 body, covered with a layer of thermal insulation, an 1 pedestal, an 4 shaft with a 5 paddle stirrer and 9 drum filter, an 2 drive, piping and an outer casing.
Fig. 7. Six section Cooking solvent for sugar syrup.
The 3 solvent housing is made of stainless steel and is a horizontal semi-cylindrical container divided by vertical 8 partitions into six interconnected sections. The sections communicate with each other by holes in the partitions, covered with 7 grooved guides, welded to the partitions to lengthen the route of the mixture through the solvent (in order to obtain a syrup of uniform concentration). Thus, the continuous movement of the solution from section to section is carried out according to the principle of communicating vessels.
In the sixth section, a rotating drum screen filter 9 is attached to the shaft. Filter screen mesh, collapsible - for easy cleaning.
The heating of the solvent is carried out with steam supplied to the 11 steam jacket, which is divided into three parts, covering two sections of solvent, so that the heating process can be controlled. Each part is covered with a heat insulation layer, over which a metal casing is put on. Condensate is removed through 12 steam traps.
To remove syrup residue from the solvent after work in the first, second and third sections of the bottom of the vertical partitions are provided holes, overlapping flaps with handles 6. During operation, valve opening overlap. From the fourth, fifth and sixth sections of the syrup after the work removed through drain valves. The sixth section provides the syrup level control 13.
The solvent is equipped with instrumentation: a thermostat for automatically controlling the temperature of the syrup, a pressure gauge, a manometric thermometer and stationary thermometers.
The granulated sugar sifted and purified from metal impurities from the sifter-dosing unit continuously flows into the first section of the solvent, and at the same time, heated water flows from the tank of the dosing-heater. Here, the mixing of granulated sugar and hot water takes place and during the passage of the solution through the first four sections, heated by heating steam through a steam jacket, the granulated sugar dissolves. In the fifth section, the sugar syrup is mixed with molasses and invert syrup. Then the sugar syrup enters the sixth section of the solvent and, after passing the filter, goes through the 10 drain valve into an intermediate collection, from where it is pumped to the places of consumption.
Technical characteristics of six section of the solvent
Syrup capacity, kg / h 2000
Solvent heating surface area, m2 4,1
Mixer rotation frequency, rpm 24
Working capacity of sections (approximately), l
second, third, fourth, fifth 200 each
Heating steam pressure, MPa 0,4-0,5
Electric motor power, kW 5,5
Rotation frequency, rpm 950
Dimensions, mm 3690x2620x1910
Weight, kg 1900
Coil vacuum pans. Continuous coil vacuum apparatuses are mainly designed for preparing caramel mass by evaporating excess moisture from caramel syrup.
Recently, coil devices are also widely used in syrup stations in preparing syrup, in boiling units for boiling fruit and berry fillings, in universal stations for boiling various candy masses, for boiling toffee, jelly, marmalade and other masses.
The confectionery industry was equipped with various types of coil apparatus. At present they are being replaced by unified devices produced by the mechanical plant "Pishchemash". In addition, the industry uses VVA-4 vacuum evaporation units of the Polimex association (PNR).
Fig. 8. Unified coiled vacuum apparatus 33-A with manual discharge masses.
Unified coil vacuum apparatus 33-A with manual unloading of mass. The unified coil vacuum apparatus 33-A (fig. 8) consists of three parts: heating /, evaporator II and separator-trap III. The heating and evaporation parts are interconnected by a pipeline. The trap is installed on the pipeline connecting the evaporation chamber with a mixing condenser and a vacuum pump.
The heating part I is a cylindrical steel case 1 with a stamped steel bottom welded to it at the bottom and a removable 2 cover. Inside the case is mounted copper coil 3, having two rows of coils connected in series. The lower end of the coil is connected to the pipeline from the syrup plunger pump supplying the vacuum apparatus, and the upper end to the connecting pipeline 4, which goes to the evaporation part of the vacuum apparatus, which in turn is connected to the mixing condenser of a piston air-cooled vacuum pump.
In the upper part of the 1 case, the heating part of the apparatus has a fitting for supplying heating steam; On the cover are mounted pressure gauge 6, safety valve 5 and valve 7 for air release. At the bottom of the apparatus there are a fitting 9 for supplying syrup, a fitting 8 for draining condensate and a tap 10 for blowing out the apparatus.
The evaporator part II of the vacuum apparatus consists of two steel shells - the upper 11 and the lower 12 - and the lower steel cone (digger) 16, interconnected by flanges and hinged bolts. Between the shell is placed cone copper bowl 13, the neck of which is covered with a valve 15. The conical bowl, the cavity of the upper shell and the spherical steel lid form the upper vacuum chamber with a capacity of 140 l. Volume of the lower conical digger 90 l. To prevent solidification of the weld mass on the walls of the 13 conical bowl, an 14 coil is mounted on the outside, in which heating steam is circulated through the 22 tube.
The top inner flap 15, openable and closable via 19 handle serves to ensure the continuity of the process of boiling (when unloading the finished weight of it is covered) and for release from the upper chamber into the lower collection cone caramel mass that accumulates during unloading apparatus.
On the upper side of the vacuum chamber on the workplace side, a 23 vacuum gauge is mounted to monitor the vacuum.
The lower cone of the vacuum chamber to prevent the height prepared by unloading the caramel mass on the 3 / 4 from hardening is washed by the heating steam supplied to the 17 steam jacket through the 22 tube. For the release of air from the 17 shirt, an 26 air valve is provided, and for periodic unloading of the finished caramel mass - an external 18 valve with a handle. The mass is monitored through the 25 viewing windows in the lower receiving part of the vacuum chamber. For the communication of the upper vacuum chamber with the lower receiver and the lower receiver with the atmosphere, a connecting tube with 21 and 20 taps is provided.
Evaporation of the vacuum device is mounted on rods 24 the ceiling or on the wall brackets.
Coil vacuum apparatus of this type are convenient for installation in production lines for the production of caramel and do not require the construction of special sites for the installation of the heating part of the apparatus. In addition, the heating part of the vacuum unit together with the plunger syrup pump and the vacuum pump can be installed at some distance from the evaporating part of the vacuum apparatus or in another room, which ensures the best sanitary condition of the workshop.
Separator-trap III, designed to trap caramel particles carried away by secondary steam, is a cylindrical steel vessel with a flat lid and a partition inside, located opposite the inlet nozzle. The delayed particles of the caramel mass are discharged through the lower branch pipe of the trap for further processing.
Caramel syrup from the syrup tank Consumables plunger pump is continuously pumped into the coil unit pressure 0,4 MPa. At the same time the housing of the heating unit through the upper fitting is supplied heating steam. The vapor space of the machine washes heating steam coil and condenses 3. The condensate is continuously removed through 8 fitting into the trap.
The pressure of the heating steam is controlled by the 6 pressure gauge; in the case of an increase in the vapor pressure above the allowable, the safety valve 5 is activated.
The caramel syrup entering the dual coil rises first along the turns of the inner coil, then passes along the vertical connecting pipe to the lower turn of the outside coil and moves further upwards along its turns; From the upper coil of the outer coil, the caramel mass passes through the 4 connecting pipe into the vacuum chamber of the apparatus, in which a vacuum is created with the help of a mixing condenser, supported by a piston-type wet-air vacuum pump connected to the vacuum chamber. Caramel mass obtained as a result of boiling caramel syrup in a coil continuously enters the vacuum chamber, while the process of boiling the mass to the final moisture 1,5 — 2,5% continues due to intensive self-evaporation of moisture in a rarefied space.
The secondary steam and the air released from the syrup during its boiling down and drawn in during the period of unloading of the vacuum chamber rush out of the vacuum chamber along a branch pipe into the mixing condenser, to which cooling water is continuously supplied; the secondary vapor, when cooled, condenses and turns into water.
The secondary steam entering the condenser occupies a significant volume - 1 kg of steam reaches a volume up to 10 м3; when turning steam into water, 1 kg of water will take about 1,0 l. Due to such a sharp reduction in volume, a vacuum is created in the condenser and in the vacuum chamber. The water-air mixture formed in the condenser is pumped out of it by a vacuum pump, due to which the vacuum in the condenser and in the vacuum chamber is constantly maintained.
A damper located at the spherical cover of the vacuum chamber prevents the caramel mass from being carried to the condenser.
With the accumulation of the final mass in a vacuum chamber it periodically,
Technical characteristics of unified coils vacuum pans 33-A
|Indicators||Performance caramel mass, kg / h|
|The heating portion|
|The surface area of the coil heating, m2||4,2||7,5|
|The diameter of the copper tube coil, mm||55X2||55X2|
|Syrup in the coil pressure, MPa||Until 0,4||Until 0,4|
|Working steam pressure, MPa||Until 0,6||Until 0,6|
|Hydraulic test pressure, MPa||Until 0,9||Until 0,9|
|Approximate steam consumption, kg / h||175||220|
|The volume of the vapor space, L||330||570|
|evaporation of the|
|Recommended residual pressure, MPa||
|The volume of the top vacuum chamber l||140|
|The volume of the lower forehearth, l||90|
|The frequency of the discharge weight, min||
|Same machine with a vacuum-discharging, kg||243|
|Recommended residual pressure, MPa||Until 0,01|
|Residual test pressure, kPa||Until 7|
every 2 min, unload, without disrupting the continuity of the process of boiling.
To unload the accumulated finished caramel mass from the bottom cone 16 of the vacuum chamber, with the top valve 15 closed, open the bottom valve 18 and simultaneously connect the bottom cone to the atmosphere, opening the 20 air cock. After unloading the mass, close the lower valve 18 and the 20 valve, then before opening the upper 15 valve equalize the pressure in both parts of the vacuum chamber, for which, with the lower 18 valve closed, open the 21 valve connecting the upper and lower parts of the chamber. After that, the 21 valve is closed, the upper 15 valve is opened, and the boiling process is continued using the full volume of both parts of the vacuum chamber.
The unified 33-A unit is available in two sizes, differing only in the size of the heat exchange surface of the coils and the height of the heating part. The performance of these devices is 500 and 1000 kg / h of caramel mass.
Unified coil vacuum apparatus 29-A with a mechanical device for unloading mass. The purpose and design of these vacuum apparatus are the same as the vacuum apparatus with manual unloading; they differ only in the presence of a mechanical device for the automatic unloading of mass.
Apparatus (. Figure 9) consists of four parts: the heating I, evaporator II, III and trap cam-lever unit IV for automatic unloading of weight.
Fig. 9. Unified coil vacuum apparatus 29-A with a mechanical device for unloading mass.
The finished caramel mass, boiled down to the desired concentration, is automatically discharged every 2 min into the funnel of the cooling machine.
A device for automatic unloading of mass periodically opens alternately the upper and lower valves of the vacuum chamber. Valves are closed by counterweights. Three cams, which are driven by means of levers and upper valve, lower valve and crane, are mounted on a single shaft, which makes a half-turn per minute. The cam block drive consists of an electric motor, a two-stage worm gearbox and a gear transmission.
Fig. 10 shows the kinematic scheme unloading machine.
The sequence of the process of automatic unloading of the mass is the same as for vacuum machines with manual unloading. Automatic mass unloading frequency - 2 min. The electric motor of the automatic unloading machine of the AOL21-4 type has the power 0,27 kW, the rotation speed 1400 r / min. The remaining data of the technical characteristics are given in table. 6.
Unified coil vacuum apparatus with a vacuum device for unloading mass. The purpose and design of these devices are similar to those described above, they differ only in the presence of a vacuum device for automatic unloading of mass.
The vacuum unloading device (fig. 11) consists of a 8 slide valve with 11 — 17 channels, 1 and 3 pneumatic cylinders, an 10 electromagnet, and electrical equipment mounted in the cabinet.
The principle of the system is as follows. Pneumatic time switches are set to the desired discharge cycle - 2 min, of which 8 s - to open the bottom valve, 20 s - to unload the mass. Depending on the requirements of the process, the time of digestion and the time of discharge can be adjusted up to 3 min. When the time relay is triggered, an electrical impulse is applied to the winding of the 10 electromagnet, the core of which, being drawn in, with a system of levers 9 turns the valve of the slide valve 8 through an angle 45 °. When the electromagnet is turned off, the spring retracts the core, returning the valve plug to its original position.
Thus, after a specified period of time, the tap of the tap rotates at an angle of 45 ° and back.
When the 13 holes are aligned, as shown in fig. 11 (section a — a, position A), the upper part of the 5 vacuum chamber is connected to the cavity of the 2 digger, while (see section b - b, position L) the channels 12 — 16 connect the cavity above the piston of the upper 3 cylinder with the upper part 5 vacuum chambers, and 11 — 17 channels connect the cavity under the top cylinder piston with? and the cavity above the piston of the lower cylinder 1 with the atmosphere.
The pistons in the cylinders move toward the vacuum side, while the 4 lever system closes the digger's 7 valve and opens the inner 6 valve to release the mass from the top of the vacuum chamber into the digger. Taxa channel location corresponds to the position of the electromagnet in the off state.
When the electromagnet is turned on, the valve of the spool valve turns at an angle of 45 ° and the channel arrangement will be as shown in fig. 11 at position B, i.e., the 15 opening (section a — a) connects the 14 chamber to the atmosphere through the 2 channel, the section XB of the 11 channel — 12 connects the cavity under the piston of the upper 3 cylinder and above the piston of the lower 1 cylinder the upper part of the vacuum chamber 5, and the channel 16 — 17 connects the cavities above the piston of the upper 3 cylinder and below the piston of the lower 1 cylinder to the atmosphere.
When the piston moves, the internal valve 6 closes and the lower valve 7 opens to unload the mass.
Bases for coiled devices are at the end of the chapter.
Fig. 10. Kinematic mechanism for unloading a caramel mass apparatus 29-A.
Fig. 11. Schematic diagram of a vacuum device for unloading the masses.
The foreign trade association Polimeks (PNR) supplies vacuum evaporators for boiling caramel mass of the type USA-3 and others, which include a boiling kettle and a coil vacuum apparatus. The productivity of the device is 350 — 400 kg / h, dimensions: 4300 X 1650 x X 2600 mm, the device is heated by steam with an overpressure of 0,6 MPa. By design, this device is similar to the coil apparatus described above. The evaporation chamber here is separated from the heating one, but both of them are mounted on the same bed.
Basic rules for servicing coil apparatus. The launch of the apparatus into the work at the end of the installation is permitted only after its registration with the organs of the State Committee under the USSR Council of Ministers on the supervision of the safe conduct of work in industry and mining supervision (Gosgortekhnadzor of the USSR).
Before starting, the device must be heated; to do this, open the common steam valve and valves for purging the coil and heating the vacuum chamber; the excess vapor pressure in this case should be no more than 0,2 MPa. After the apparatus is warming up, close the coil purge valve, and then the valves of the vacuum chamber and the lower receiving cone, turn on the wet-air vacuum pump, open the valve on the syrup pipeline, turn on the food pump (if the device is equipped with automatic unloading, turn on the automatic unloading machine) and open the valve on steam line to gradually obtain the working pressure specified in the passport.
In order to avoid sugaring the coil, at least 2 should be washed once a shift with hot water at a temperature of approximately 90 ° C, passing it through the syrup feed tank, syrup pump and apparatus. At the same time, the flush sweet waters are diverted through special pipelines to the collection and after filtration are disposed of when preparing syrups and fillings.
To remove a vacuum apparatus that is formed during the operation of a scale or scale inside the coil, it is subjected to a thorough etching of 2 — 3% solution of caustic soda (or to accelerate the pickling — 5% solution) for 30 — 40 min. passing the solution through the syrup tank, plunger pump, coil, vacuum chamber and back. After etching, thoroughly flush the apparatus with hot water.
When using coil vacuum apparatus for boiling fruit filling from the initial humidity 40 — 50% to the final 17 — 20%, the heating steam overpressure is maintained within 0,3 — 0,4 MPa, and the volume of the vacuum chamber to prevent the entrainment of the mass into the secondary condenser steam increase 5 — 7 times; in addition, a trap is set, the residual pressure in the vacuum chamber is maintained up to 45 kPa.
Non-vacuum boiling of fillings in the coil heating part of such devices is also practiced. In this case, instead of a vacuum chamber for suction of the secondary steam, a steam trap with a fan is installed. The heating part of the coil apparatus with steam trap is also used for continuous boiling candy, toffee, marmalade and other confectionery masses.
Film heat exchangers. Effective by intensifying heat exchange processes is boiling or cooling syrups flowing down a vertical surface with a thin layer, and a promising device design is vertical rotary film apparatuses.
The main advantages of film machines are: high intensity of heat and mass transfer, short residence time of the solution in the zone of high temperatures, lack of hydrostatic pressure. Liquid film in these devices is created in various ways. According to the method of creating a film, film devices can be divided into the following types: 1) devices with a creeping film; 2) falling film apparatuses; 3) centrifugal devices; 4) devices with rotary device.
The study of the possibility of using rotary type film apparatuses for boiling the confectionery masses was conducted at the All-Union Scientific Research Institute of the Confectionery Industry. It was found that obtaining caramel mass in a film apparatus can reduce the duration of boiling syrup from 3 — 4 min to 10 — 15 with while improving the quality of the caramel mass. In addition, on the basis of the work carried out, the possibility of obtaining a caramel mass directly from sugar and molasses was proved, bypassing the stage of preparing the syrup.
The research results allowed to substantiate the new method of melting crystalline sugar by heating it in a thin layer. In order to accelerate the process, improve the quality of the melt and protect the heat transfer surface from the formation of soot, heating is performed with simultaneous forced movement, grinding substances to a powdery mass and mixing it to a uniform state. Duration of melting by this method 15 — 30
Production tests of an industrial apparatus for preparing roasted mass with a capacity of up to 80 kg / h of sugar gave positive results.
Structurally, rotor-type film apparatus is distinguished by a vertical or horizontal arrangement of the rotor shaft with scrapers fixed on it.
Currently, two types of vertical rotary apparatuses are most widely used: the apparatus with radial rigid blades and the apparatus with sliding scrapers.
In the apparatus of the first type, the blades are rigidly fixed on the rotor with a gap in 1 — 2 mm between the heat exchange surface and the working edge of the scraper.
In a film apparatus with sliding scrapers, the latter, when the rotor rotates under the action of centrifugal forces, are pressed against the wall and slide along the internal surface of heat exchange, forming a thin film of liquid on it.
In fig. 12 shows the vertical film apparatus VNIIKPa. for lipstick. The device is a cylindrical body with sectional jackets 6 for the passage of coolant. The rotor shaft 3 rotates in the outboard bearings 1 and 8. In the upper part of the body there is a steam trap 2. The 4 distribution disc is attached to the shaft. Syrup, getting on this disk, under the influence of centrifugal forces is sprayed on an internal surface of the case and flows down on it in the form of a film. In addition to the disk, 7 blades and vertical 5 scrapers are inserted into their grooves.
Scrapers promote leveling of the layer of flowing liquid, and the blades create a ventilation effect inside the apparatus. The rotor speed is 400 rpm. The total surface area of heat exchange is about 0,54 m2 with a capacity of up to 150 kg / h. The case of the device has a diameter of 200 mm. The height of the working area of the device is 1000 mm. Dimensions of the device 950 X 550 X 2300 mm.