RU67240U1 - DEVICE FOR DRYING AND THERMAL PROCESSING OF BULK MATERIALS - Google Patents

Abstract

The utility model relates to devices for drying and heat treatment of bulk materials and can be used in energy, chemistry, petrochemicals, food industry, in the production of building materials and mineral fertilizers. Improving the quality of the dried bulk material, in particular its moisture uniformity, and increasing fuel efficiency is achieved by eliminating the direct contact of the dried material and hot exhaust gases generated during fuel combustion during the drying process, as well as by increasing the surface area heated by the exhaust gases, which is in contact with the material with constant mixing of the drained material, due to the introduction of coaxially arranged pipes inside the rotating cylinder, Without which the exhaust gases pass from the furnace to the exhaust manifold and then to the exhaust pipe. 1 Ill., 3 C.p. f.

Description

The utility model relates to devices for drying and heat treatment of bulk materials and can be used in energy, chemistry, petrochemicals, food industry, in the production of building materials and mineral fertilizers.

Known dryer for bulk materials (SU 1252630), containing a rotating drum with nozzles for supplying and discharging coolant, a distribution box made along the entire line of the drum and fixedly connected to the nozzles for supplying and discharging coolant. A disadvantage of the known device is the difficult drainage of water from the bulk material due to the formation of a dense layer on the surface.

A device is known for drying bulk materials with flue gases (RU 2015466), where drying is carried out with flue gases in an upward flow of a gas suspension with a preliminary decrease in the temperature of the flue gases before they are fed to the material to be dried by means of a heat pipe. The disadvantage of this method is the low economic efficiency of the method and the pollution of the material by flue gases.

A known method of drying bulk building material (RU 2133643), selected as a prototype, providing heating and drying of building materials, including the supply of raw material to a drum dryer, where the flow of hot gases in countercurrent to the movement of the dried and / or calcined material. However, the main disadvantage of this method is the contamination of the drained material with incompletely burned fuel and solid or liquid combustion products.

The technical result obtained by the implementation of the proposed utility model is to improve the quality of the dried bulk material, in particular its uniformity in humidity, and increase fuel efficiency.

The specified technical effect is ensured by eliminating during the drying process direct contact of the drained material and hot exhaust gases generated during fuel combustion, as well as by increasing the surface area heated by the exhaust gases, which contacts the material with constant mixing of the drained material. This is achieved by introducing into the rotating cylinder several coaxially arranged pipes through which the exhaust gases pass from the furnace to the exhaust manifold and then to the exhaust pipe.

The design of the proposed device is shown in figure 1, which shows:

1 - filling neck;

2 - an exhaust collector;

3 - the bottom of the drainage heating chamber;

4 - drainage and heating chamber;

5 - roller bearings;

6 - a restrictive ring;

7 - persistent rollers;

8 - drive drainage heating chamber;

9, 10 - cylindrical parts of the drying and heating chamber;

11 - adapter;

12 - heating tubes;

13 - thermal insulation;

14 - a furnace with a combustion chamber;

15 - lodgement of the furnace;

16 - support lodgement;

17 - a ring;

18 - burner;

19, 20 - gas-dynamic labyrinth seals;

21 - an exhaust pipe;

22 - blower;

23, 24 - temperature sensors;

25 - damper drainage heating chamber.

The utility model device has the following design:

The filling neck 1 passes through a stationary exhaust manifold 2 and has an open exit through an opening in the bottom 3 into a rotating drying and heating chamber 4 mounted on roller bearings 5 with the possibility of adjusting its inclination to the horizon. The camera 4 is equipped with a restrictive ring 6 fixed on it, which, together with the thrust rollers 7, mounted on the supports 5, eliminates the axial displacement of the camera rotating by means of a drive 8 having a speed control function. The chamber 4 consists of two cylindrical parts 9 and 10, interconnected by a truncated conical adapter 11. Inside the cylinder 10, heating tubes 12 are placed coaxially in several rows, fixed in the corresponding holes on the conical adapter 11 and the bottom 3 of the cylinder 10. All high-temperature parts of the installation are exhaust manifold 2, cylinders 9 and 10, adapter 11, shutter 25 - have thermal insulation 13, which reduces heat energy loss, increases the temperature inside the unit and protects the operating personnel from thermal burns. The cylinder 9 passes through the combustion chamber of the furnace 14. The furnace 14 is mounted and mounted on a lodgement 15 with supports 16. The open end of the furnace 14 is closed by a ring 17 with a burner 18 mounted on it for liquid or gaseous fuel. The rotating chamber 4 is connected to the stationary firebox 14 and the exhaust manifold 2 through labyrinth seals 19 and 2, respectively. A blower 22 is inserted into the exhaust pipe 21 connected to the collector 2, which together with the nozzle 18 controls the temperature distribution inside the chamber 4, and together with the gas-dynamic labyrinth seals 19 and 20 eliminates the leakage of exhaust gases through them. To control the temperature in the combustion chamber of the furnace 4 and the exhaust pipe 21, temperature sensors 23 and 24 are installed, respectively. The damper 25 at the open end of the pipe 9 increases the completeness of the use of fuel energy, regulates the extraction from the chamber 4 of moisture removed from the material, as well as the yield of the finished product.

A device for drying and heat treatment of bulk materials works as follows:

Liquid or gaseous fuel is supplied to the nozzle 18 and ignited. The rotation of the chamber 4 begins with the help of the drive 8. Thermometers 23, 24, the blower 22 and the shutter 25 controls the achievement of the required temperature values in different parts of the installation. The processed material is fed into the filling neck 1 and through it into the chamber 4, where it contacts the tubes heated by the exhaust gases and is mixed with them. Due to the speed of rotation and tilt to the horizon of the chamber 4, the residence time of the processed material in the installation is regulated. The material that is deprived of water becomes crumbly and is subjected to the highest temperature treatment when it is in the pipe 9, which passes through the combustion chamber of the furnace 14. Moisture removed from the material in the form of water vapor exits the chamber 4 through the annular gap between the filling neck 1, collector 2 and bottom 3.

A device for drying and heat treatment of bulk materials can be made of ordinary or stainless steel, depending on the nature of the dried and heat-treated material, as well as taking into account the requirements for the purity of the finished product. So, when drying quartz sand for its subsequent fractionation, a device made of ordinary steel can be used, since relatively little moisture is released, it does not contain alkali and acid, and high temperature in the drying-heating chamber is not required - more than 300-400 ° FROM. For drying and heat treatment of calcium hydrosilicate after its hydrothermal synthesis in order to turn into calcium silicate (wollastonite), especially taking into account the purity requirements of synthetic wollastonite, the device will need to be made of stainless heat-resistant steel. In this case, the steel parts of the device will withstand temperatures up to 1400 ° C, which can be achieved in the furnace chamber during the combustion of fuel oil, heating oil, diesel fuel or gas.

The diameters of the cylindrical parts of the device and their lengths are calculated based on the required plant performance, the initial and final humidity of the processed product, as well as the heat treatment temperature and its duration. The same parameters affect the choice of nozzle type and its performance.

Examples of device implementation.

1. For drying sand, the installation of the proposed design was made of steel with a length of cylindrical parts of 3 m each and their diameters of 270 mm and 630 mm, respectively. The nozzle with a thermal capacity of (70-100) kW provided the temperature of the drying and heating chamber in the range of 300-400 ° C.

The productivity of the installation allowed the drying process of 2 tons of quartz sand with an initial moisture content (4-6)% to a final moisture content (0.1-0.2)% in one hour.

2. For the heat treatment of calcium hydrosilicate, the installation of the proposed design was made of stainless heat-resistant steel with a length of cylindrical parts of 3 m each and their diameters of 270 mm and 630 mm, respectively. When burning fuel oil, heating oil, diesel fuel or gas in the combustion chamber in the drying chamber, a temperature of up to 1400 ° C was ensured.

The plant’s performance allowed heat treatment of 150 kg of calcium hydrosilicate, having an initial moisture content of (40-50)%, at a temperature of 700 ° C for 15 minutes until it was completely converted to calcium silicate.

Claims (2)

1. A device for drying and heat treatment of bulk materials, including a filler neck passing through a fixed exhaust manifold and connected through a hole in the bottom with a rotating drying and heating chamber, a drying and heating chamber mounted on roller bearings with the possibility of adjusting its inclination to the horizon, and consisting sequentially of two cylindrical parts interconnected by a truncated conical adapter, rows of heating tubes coaxially located in the first qi of the indric part and fixed in the corresponding holes on the conical adapter and its bottom, the combustion chamber with the combustion chamber, mounted on the lodgement and supports so that the second cylindrical part is located inside the combustion chamber of the furnace, the open end of the furnace being closed by a ring with a burner mounted on it for liquid or gaseous fuel, and a rotating drying and heating chamber is connected to the furnace and the exhaust manifold through the corresponding labyrinth seals, respectively, in addition, in the exhaust pipe, Connections to the exhaust manifold is disposed a blower, temperature sensors are installed in the combustion chamber of the furnace and, respectively in the exhaust pipe and the open end of the second cylindrical part located damper regulating the yield of the finished product and exhaustion of the chamber remote from the moisture in the material. 2. The device according to claim 1, where the drying and heating chamber, rotating by means of a drive with an adjustable speed, is equipped with a restrictive ring fixed on it and thrust rollers resting on a roller support.