SU743973A1 - Method of cooling claydite gravel - Google Patents

Description

The invention relates to the field of building materials, namely the production of expanded clay.

A known method of cooling expanded clay gravel by irrigation with sprayed water or cold air [1].

However, with excessively intensive cooling of expanded clay, some of the granules are destroyed. 10

The closest technical solution to the invention is a method for cooling expanded clay gravel, which includes cooling with water and water vapor, in which the expanded clay is cooled to a temperature of 300-500 ° C by air, after which the expanded clay is cooled with water vapor obtained from water cooling [2] .

A disadvantage of the known method is the mandatory cooling of expanded clay 20 with air in the first stage, which leads to an increase in the volume of cooling equipment and a cooling agent, therefore, the complexity of the process, as well as the partial destruction of keramsite 25.

The purpose of the invention is to reduce the volume of the cooling agent, simplifying production and increasing the strength of expanded clay gravel. thirty

This is achieved by the fact that in the proposed method for cooling expanded clay gravel, including cooling it with water and water vapor obtained from cooling gravel with water, water vapor is cooled from 1100-900 to 550-500 ° C at a rate of 20-40 ° C / mpy, then cooled with water to 40-50 ° C.

The technology of the method is as follows. Expanded clay grains after firing from a temperature of 1100–900 ° С are cooled with water vapor to a temperature of 550–500 ° С at a rate of 20–40 ° С / mnn.

Water vapor for cooling expanded clay gravel in the first stage (from 1100-900 to 500-550 ° C) is obtained from water cooling expanded clay in the second stage (up to 40-50 ° C). In the process of cooling, expanded clay gravel is fed from top to bottom: first, into a stream of water vapor, then into water. An excess of the high-temperature water vapor generated in this process is also sent to the heat treatment zone of the furnace to intensify the heat treatment process and utilize its heat.

To maintain a given temperature and humidity regime c. The amount of water in it is kept constant and equal to 0.18-0.20 t / t expanded clay gravel.

This method of continuous two-stage cooling ensures the creation of a soft regime in the first stage, which promotes crystallization of the glass phase and the formation of a solid gravel structure, and in the second stage creates an intensive cooling regime in water and water vapor.

Example p. Expanded clay grains 16 × 6 mm in size are formed on a press from clays of the Malo-Babchik deposit in Kerch at a moisture content of 29%, dried at 105 ° C and calcined at 1100 ° C for 7 minutes. Heat treatment time - 28 minutes. These parameters simulate the conditions for firing expanded clay gravel in a rotary kiln.

Cool the granules as follows.

In the first stage, from the swelling temperature (1100 ° С) to 500 ° С - water vapor at a speed of 40 ° С / min. The cooling time at the first stage is 15 minutes with a steam flow of 0.2 t / t expanded clay gravel. The temperature of the steam after cooling is 900-1000 ° C.

In the second stage (from 500 to 50 ° C), the granules are immersed in water for 3 s. Water consumption is 0.2 t / t expanded clay gravel. The average compressive strength at a bulk density of 450 ± 10 kg / m ³ is 32 kg / cm ² , which is 3 kg / cm ² (10%) more than by the known method. High-temperature 15 pairs are fed into the heat treatment zone, which intensifies the process.

The table shows the comparative characteristics of the known and this methods of cooling expanded clay gravel.

Indicators

The method of cooling expanded clay gravel

Famous

Proposed

The minimum amount of cooling agent upon cooling from 1100 to 500 ° C expanded clay gravel, t / t

The maximum temperature obtained by cooling water vapor, ° C

The volume of the cooling space of the layer refrigerator, m ³

Coolant heat recovery

Average strength at Y = 450 ± 10 kg / m ³

0.24 0.20 300-400 800-1000 thirty 25 For heating To the heat treatment zone 29th 32

Using this method of cooling expanded clay gravel can significantly reduce the volume of the cooling agent and equipment by eliminating air cooling and, thus, simplify the production of expanded clay, to obtain high-temperature steam with a temperature of 2.5-2.7 times higher than in the known method, intensify heat treatment by 15-20% and ensure complete utilization of heat. The strength of expanded clay gravel in this case increases by 10%. The economic effect of using this method for a plant with a productivity of 100 thousand m ³ / year is 24 thousand rubles.

Claims (2)

Claim A method for cooling expanded clay gravel, including cooling it with water and water vapor obtained from cooling gravel with water, characterized in that, in order to reduce the volume of the cooling agent, simplify the production process and increase the strength of expanded clay gravel, water vapor is cooled from 1100–900 to 550— 500 ° C at a rate of 20-40 ° C / min, then cooled with water to 40-50 ° C. 30 Sources of information taken into account in the examination 1. Goryainov K. E. Technology of mineral heat-insulating materials and light- 35 concrete. M .., "Stroyizdat", 1976, p. 408-409. 2. Copyright certificate of the USSR on application No. 2488176, cl. C 04B 31/02, 1977 (prototype).