SU968560A1 - Unit for heat treating of mineral suspenions - Google Patents

Description

(5) INSTALLATION FOR HEAT TREATMENT OF MINERAL

suspension

Claims (2)

The invention relates to the technique of heat treatment of mineral suspensions and to be used in the building materials industry, chemical and food industries, for example, in the regeneration of lime from a filter cake of dry-sourced production. Installations for the heat treatment of mineral suspensions are known, which contain in the upper part a spray drying chamber with a dispersant and a C1 3 fluidized bed chamber underneath it. However, these installations are characterized by low productivity and the inability to use a high-temperature heat transfer fluid, closer to the technical essence and achieve a reasonable result To the proposed is a device for) 6pa6oTKH mineral suspensions containing dispersants for spraying sprays, a cylindrical drying chamber, matic coupler and the high-temperature chamber with the established. tangential nozzles of coolant inlet t2. However, the known installation does not allow working with different performance at a constant content of carbon dioxide in the exhaust gases, for example, with a capacity of 5-10 times less than the nominal one. The need to maintain a constant CO content in waste gases is caused by using them, for example, in the process of cleaning the diffusion juice of sugar production. In this case, the minimum allowable CO content in the exhaust gases should be 30%. At the same time, fuel consumption is limited, since an increase in the consumption of fuel burned in a high-temperature chamber leads to a decrease in the CO2 content. in exhaust gases. If it is necessary to reduce the capacity of the installation, the nominal heat carrier burned in the high-temperature chamber is reduced by a factor of a smaller than nominal. In this case, the aerodynamic mode of operation of the chamber is disturbed, as the flow swirl is reduced and heat treatment becomes impossible. Increasing the amount of coolant to maintain a normal aerodynamic regime is impossible, since it leads to a decrease in the content of CO2 in the exhaust gases. The installation of two heat treatment chambers of different cross-sections coaxially, successively one after another, leads to a significant increase in the overall installation height. The construction of two plants of different capacity leads to an increase in production space. The aim of the invention is to enable the operation of the plant with different capacities at a constant content of carbon dioxide in the exhaust gases. The goal is achieved by the fact that the high-temperature chamber has a horizontal connector, and the lower part of the chamber below it is movable and mounted on a platform with the possibility of reciprocating movement, the platform being additionally equipped with at least one lower part of the high-temperature chamber of another size. The drawing shows schematically the proposed installation. The installation contains dispersants 1 for spraying a heat-treatable mineral suspension supplied through pipes 2, a cylindrical drying chamber 1 3, a conical adapter k, an upper part 5 of the high-temperature chamber connected to it. The installation contains two interchangeable lower parts 6 and 7 of a high-temperature chamber of different cross section, connected by a common unloading device 8 and installed on a mobile platform 9- The heat carrier enters the high-temperature chamber through a tangential nozzle 10. The exhaust gases are removed from the drying chamber 3 through pipe P. Parts 6 and 7 of the high-temperature chamber have a different cross section, for example, the cross-sectional area of part 7 is 10 times smaller than the cross-sectional area Section 6. Installation works as follows. Thermoablative mineral suspension, for example, a slurry of a filter cake from sugar production, which has the following chemical composition, wt .: CaCO 8f, organic additives 15, moisture: (5–50, supplied under pressure (20–25) –1 O n / M to dispersants 1 and is sprayed in a cylindrical drying chamber 3 into a stream of gaseous heat transfer fluid coming from a high-temperature chamber with a temperature of 500900 C. At that, the temperature in the drying chamber 3 is 150-250 C. The dried fine granulated material is under the influence of its own the weight falls on the surface of the conical adapter 4 and falls over it into the upper part 5 of the high-temperature chamber. Depending on the desired performance, part 6 or part 7 of the chamber can be installed under the top part 5. The installation of these parts 6 and 7 is provided by the reciprocating movement of the platform 9 in the direction perpendicular to the axis of the chambers. For example, in the drawing, under the upper part 5 is installed, part 6, the cross section of which has a large section of part 7 10 times (the nominal installation capacity). Through tangential nozzles 10, a heat carrier with a temperature of 800–1200 ° C is introduced into the high-temperature chamber. In this case, an upward vortex flow of the coolant is generated in this chamber, moving at a tangential speed of 30-50 m / s. Microgranules of the material, moving from top to bottom, are heated in countercurrent with heat-transfer agent to 950-1 and decarbonated to form calcium oxide and carbon dioxide. At the same time, the consumption of fuel supplied to the high-temperature chamber is 0.09-0.15 kg cond. per 1 kg of lime (.CaO) with an activity of 90. With this fuel consumption, the percentage of carbon dioxide in the exhaust gases discharged from the drying chamber 3 is 3032%. Reducing the C01 content in the exhaust gases below 30 is unacceptable, as it makes them unsuitable for cleaning the diffusion juice of sugar production. In this connection, it is unacceptable to increase the consumption of heat supplied to the heat treatment above the given values. The finished product (lime) is discharged from the bottom of 6 or 7 of the high-temperature chamber by means of a discharge device 8. Exhaust gases from the drying chamber 3 are sucked off by a fan (10) (not shown) through pipe 11. In case of a need to convert the plant to capacity , 5-10 times smaller than the nominal, by moving the platform 9 15 to the left, the part 6 is quickly replaced by part 7. The coolant is fed through nozzles 10 into part 7. The specific flow of the coolant remains the same, and the total flow 20 decreases in proportion to the amount of product (lime) produced. As a result, an optimal aerodynamic operation of the high-temperature chamber is maintained. The pro-2s percent carbon dioxide content of LS02.} In exhaust gases, due to constant specific fuel consumption, remains constant. Parts 6 and 7 of the high-temperature chamber are connected by 30 common discharge device 8, which simplifies the process of their replacement and ensures the continuity of the production cycle. The implementation of the high temperature chamber as two separate parts, the upper part of which is rigidly connected to the conical adapter, and the lower part is movable and can move back and forth in the direction of the scientific research institute, perpendicular to the axis of the upper part of the high temperature chamber, allows to carry out a rapid change in the design of the installation in the event of the need to work with different performance (if it is changed in RPZ). At the same time, the specific fuel consumption remains unchanged, which makes it possible to maintain a constant content of carbon dioxide in the exhaust gases. To achieve such goals with the help of well-known constructions, two autonomous installations would be required. Therefore, when using the proposed plant, the production area is reduced,. The invention The apparatus for the heat treatment of mineral suspensions, comprising a cylindrical drying chamber with dispersants for spraying the suspension and connected to it by means of a conical adapter, a high-temperature chamber with tangential nozzles for introducing a heat carrier, which is different in that Constant carbon dioxide content in exhaust gases; the high-temperature chamber has a horizontal connector and is located below it the lower part of the chamber is movable and mounted on a Platform with the possibility of reciprocating movement, and the platform is additionally equipped with at least one lower part of a high-temperature chamber of another size, Information sources taken into account during the examination 1. M. Lykov, B. Leonchik. . Spray dryers M., Mashinostroy, 1966, p. 229. 2. USSR author's certificate -Y ° 613176, cl. F 2b 3/12, 1976.