RU2194027C2 - Device for preparation of slaked lime - Google Patents

Abstract

FIELD: construction engineering; devices for preparation of slaked lime. SUBSTANCE: device has feeder and reactor with unit for supply of water from water reservoir. It is provided with loading bin, funnel for finished product, hermetic chamber located near reactor and additional reservoir for supply of water located in hermetic chamber and connected with water supply unit and water reservoir. EFFECT: intensification of lime slaking process. 1 dwg

Description

 The invention relates to the production of building materials and can be used to obtain slaked lime.

 Known devices for the production of slaked lime, including a reactor in which a hydration reaction occurs, devices for supplying the starting products — quicklime and water and / or steam, devices for unloading the finished product, underflow, vaporous hydration waste [1-7].

 All known devices are aimed at reducing energy consumption to obtain slaked lime and / or increasing the percentage of yield of slaked lime.

 To reduce energy losses, to eliminate or simplify the drying operation, they reduce the moisture content of the obtained product, using steam [4] for hydration instead of water, dosing the water supply through nozzles, nozzles [1, 2, 3, 4, 6] or the highly moistened final product is not dried, and kept in a closed container, as a result of which free moisture passes into hydration [7].

 To increase the yield rate of the finished product, the reactive surface of the quicklime pieces with water and / or steam is increased by crushing the feedstock in crushers [6, 7], mixing it with water and / or steam by means of mixers of various designs [6], by rotating the reactor itself [ 4], shaking on vibration gratings [1, 3], rubbing water into the surface using nozzles of various designs associated with drives [2], conducting a multi-stage reaction, when unreacted pieces are subjected to additional processing [1, 3 , 4], increasing the reaction time [2, 7]. In addition, to further increase the yield percentage, reduce losses of the finished product, it is separated from unreacted lime [1,3,4,5,6] and vapor extinguishing waste by constructing reactors with discharge devices, exhaust devices, ducts, etc. [1 , 3, 5, 6].

 The best of the considered solutions and the closest analogue is the device for the patent application "Method for the production of slaked lime and a device for its implementation" by the authors Aksenova VI, Koroleva TS, Khozina V.G. ref. 7 of March 10, 2000 [8].

 This device, comprising a housing - a reactor with a water supply device, a feed hopper of the initial product with a feeder, a discharge funnel for the finished product, is equipped with a sealed chamber connected to the reactor by means of a discharge pipe, or the reactor itself is placed in a sealed chamber, which is a more preferred embodiment of the device moreover, the sealed chamber is made with a condensate collector with hydrated lime in its lower part, connected with a reservoir with water for feeding it into the reactor - a sump.

 The disadvantages of the closest analogue is the insufficiently intense quenching process due to the supply of cold water to the reactor. Water can be heated with a heater, but this requires additional energy costs, complicating the process of producing slaked lime. Another disadvantage is the insufficient adjustment of the vapor pressure in the sealed chamber during a sharp change in the composition of the initial product, for example, when supplying raw materials with a high content of active CaO and MgO or more finer, when the quenching process in the reactor goes more intensively, more steam will be formed, and its pressure in a sealed chamber will increase sharply, since the pipe connecting the sealed chamber with the sump will not cope with the increased pressure.

 The objective of the invention is to intensify the quenching process by supplying hot water without additional energy costs, heating the water by utilizing the heat generated by hydration, and also additional pressure relief in the sealed chamber with a sharp change in the quality of the feedstock being loaded.

 The problem is solved in the known device for extinguishing lime, including a housing - a reactor with a device for supplying water, a hopper for loading the initial product, a funnel for unloading the finished product, an airtight chamber associated with the reactor and a water tank, in which the sealed chamber is equipped with an additional water tank connected with water dispenser and sump. The volume of the indicated capacity and the surface of the water mirror depend on the volume of the reactor load and the amount of liquid supplied to the reactor, the ratio of the volume of the sealed chamber and the reactor, which are calculated empirically using conventional engineering calculations.

 The device shown in the drawing.

 The lime extinguishing device comprises a reactor 1, a loading hopper 2 with a feeder 3, a finished product funnel 4 with a dividing net 5, a finished product nozzle 6 and an underflow nozzle 7, a water supply device 8. The device also includes a sealed chamber 10. The reactor 1 can be connected with a sealed chamber 10, for example, by means of a branch pipe either in another way (not shown) or placed inside the chamber 10. The sealed chamber 10 is provided with a pit 11 or is made with any volume in its lower part (condensate collector with slaked lime Tew) for collecting condensate with dissolved particles of slaked lime. The sump 11 is connected with the sump (water tank) 9 directly, if the sump is below the sump, or by means of a pumping device (not shown). The sealed chamber 10 is equipped with an additional tank with water 13, placed in its inner part, and is connected with the sump 9 by the pipe 12, and the tank 13 with the sump 9 - pipe 14.

 The device operates as follows.

 Quicklime in the form of pieces is continuously or periodically fed from the loading hopper 2 through the feeder 3 to the reactor 1, depending on their size and the rate of the hydration reaction. In this case, the pieces self-grind, forming dust from finely divided particles of quicklime, which, rising up, enters the sealed chamber 10. The rotation of the reactor intensifies the process of self-grinding of lime and the formation of dust from quicklime. Through a nozzle 8, connected with a capacity of 9, water is fed in a thin stream continuously or in portions into the reactor 1 and, irrigating pieces of quicklime, begins to react with it, extinguishing it. The rotation of the reactor contributes to a better contact of water with quicklime, intensifying the quenching process. In this case, a large amount of heat is released and water is converted into steam, which is also involved in the process of extinguishing lime. Steam treatment of lime is accompanied by fluidization - a combination of finely dispersed extinct lime particles with particles of steam. The resulting fluidized composition rises up as a lighter fraction to the outlet of the reactor and is "poured" out of it into the funnel of the finished product 4 and delivered through the net 5 to the finished product warehouse 6. The rotation of the reactor contributes not only to grinding pieces of lime, but also mixing them , moving the reacted particles up, and the unreacted particles down, i.e. separation of the finished product from unreacted residues.

 The operation of extinguishing in the reactor occurs with the release of the smallest slowly quenching particles of unreacted lime, which also rise up and, leaving the reactor, increase the concentration of suspended particles of unreacted lime in the volume of the hermetic chamber 10. When water is supplied to the reactor from the nozzle 8, there is constant heat generation and continuous the formation of steam, which is sufficient for steam saturation of the reactor; the quenching process occurs quite intensively and in this case, excess steam leaves the reactor, enters the sealed chamber, forming an additional reserve of steam; while the water in the additional tank is heated and then fed into the reactor already heated, without requiring its special heating; in a sealed chamber there is a sufficiently large number of non-extinguished particles of lime, which enter into a hydration reaction with steam. The resulting slaked lime, condensing, is collected in the lower part of the pressurized chamber (condensate collector 11) in the form of milk of lime, which is pumped into a container of water 9. In this case, the vapor pressure in the pressurized chamber 10 decreases and its new portions are filled with small particles of quicklime lime and steam. The process of vaporization is regulated by changing the amount of water supplied for the reaction.

 The milk of lime 9, which has got into the tank with water, settles, and highly hydrated slaked lime accumulates in the lower part of the tank, which is sent to the consumer in the form of lime test.

 By changing the loading mode (for example, by reducing the size of the pieces of the initial product, reducing the concentration of impurities), the conditions of the hydration reaction in the reactor change, as a result of which the steam in the reactor can become much more than the optimal amount, and it is impossible to track it instantly by conventional means. In this case, the vapor concentration in the sealed container increases sharply and can exceed the critical one. When this occurs, the interaction of steam and steam with particles of reacted lime with water in the additional tank 13, and their condensation; the larger the surface of the water mirror, the more effective the condensation. As a result of condensation, the container 13 is filled with milk of lime, the vapor pressure in the sealed chamber decreases, which favorably affects the maintenance of the optimal mode of vaporization in the device and the general process of steam exchange. When exceeding in the tank 13 of the milk of lime of a certain level, the excess is drained through the pipe 14 into the sump 9.

 Thus, the presence of a container of water in the sealed chamber provides heating of the water and the supply of hot water to the hydration reactor, which intensifies the quenching process, increasing the productivity of the device and the percentage of slaked lime output, and also allows relieving excess pressure in the sealed chamber in extreme situations. Additionally, there is a collection of milk of lime in the tank 13, which also increases the percentage of output of the finished product.

Sources of information
1. Copyright certificate 311877, IPC C 04 B 1/06, Bull. 1971, 25.

 2. Copyright certificate 317630, IPC C 04 B 1/06, Bull. 1971, 31.

 3. Copyright certificate 857037, IPC C 04 B 1/08, Bull. 1981, 31.

 4. Copyright certificate 933646, IPC C 04 B 1/08, Bull. 1982, 21.

 5. Copyright certificate 1463724, IPC C 04 B 2/08, Bull. 1989, 9.

 6. Copyright certificate 1521721, IPC C 04 B 2/08, Bull. 1989, 42.

 7. Patent 1811514, IPC C 04 B 2/04, Bull. 1993, 15.

 8. Application for a patent for the invention "Method for the production of slaked lime and a device for its implementation" by the authors Aksenova VI, Koroleva TS, Khozina V.G. ref. March 7, 2000 - prototype.

Claims (1)

 A device for producing hydrated lime containing a feeder, a reactor with a device for supplying water from a water tank, characterized in that it is equipped with a hopper for loading, a funnel for the finished product, a sealed chamber at the reactor and an additional water supply tank located in a sealed a chamber and associated with a water supply device and a water tank.