SU966062A1 - Method for roasting cement clinker in rotary kiln - Google Patents

Description

The invention relates to the building materials industry, j mainly to cement production, where it can be used to burn cement clinker in rotary kilns.

There is a known method for firing prtlandland cement clinker in a rotary kiln by burning gas fuel in the presence of air entering the kiln directly from the cooler l.

The closest to the proposed technical essence and the achieved effect is a method of burning cement clinker in a rotary kiln, by supplying electrical materials - fishing from the cold end of the kiln, introducing fuel and air necessary for burning from the hot end of YG}. Low intensification of firing processes and the presence of clinker dusting, which impedes the operation of the refrigerator and worsens the operation of the kiln.

The purpose of the invention is to reduce clinker dust and fuel consumption.

The goal is achieved by the fact that according to the firing method

Cement clinker in a rotary kiln, by feeding raw materials from the cold end of the kiln, introducing the fuel and air necessary for burning from the hot end, a portion of air is supplied to the boundary between the sintering zones and the cooling jet with an opening angle of 30-120 and pressure . 150-350 kg / mch

ten

FIG. 1 is a diagram of a rotary kiln; a longitudinal section in FIG. 2 is the same cross section. . , :

Receiving fuel

15 in a clinker kiln with a flame temperature of 1600-1700 ° C; mine for a complete completion in a relatively short time of the chemical processes of clinker-forming

20 calls, are introduced into the rotary kiln I through 1 nozzle 2 with or without a part of air, depending on the type of fuel and the burners used to burn it.

25

Simultaneously, from the gbr of the end of the furnace, a separate nozzle 3, installed below the fuel one, at the boundary between the sintering and cooling zones, serves a portion of the air collected

30 directly from the refrigerator and having a temperature of ZOO-HEO C, and the air is supplied with a jet 4 with an opening angle oi- equal to 30-120 and ensuring its penetration, 1 / 3-1 of the chord length of materials - AB catch and under pressure 150 - 350 kg / m The opening angle of the air stream and the amount of pressure under which air is supplied depend on the particle size distribution of the calcined material 5. The lower limits of their values correspond to the minimum, and the upper ones to the maximum content in the clinker of granules with particle sizes of 0.01 -5 mm. The remainder of the air required for combustion; fuel enters the furnace from the refrigerator due to the vacuum in the furnace. When in contact with clinker, the air supplied by the air is heated up and ensures complete combustion of fuel in the sintering zone. Small clinker particles are returned with an air stream to the sintering zone and again participate in the process of forming clinker granules. As a result, clinker dust and small clinker particles are full of granules and into the cooling zone, and then a clinker with a size and mass of granules that prevents their return from the air from the refrigerator to the rotary kiln enters the refrigerator. . The proposed method of burning cement clinker is illustrated by the following example. When burning clinker in a rotary kiln furnace, for example, dimensions 5x185 m, having a capacity of 72 t / h and specific heat consumption for clinker burning -1500 kcal / kg, according to approximate calculations, for burning 1 kg of equivalent fuel, it is necessary to introduce 8.5 nm into the furnace air. On average, 14.5 thousand kilograms of fuel equivalent per hour is burned in such a furnace, which requires the introduction of 123.5 thousand nanometers of air into the furnace. A part of this air, for example 10%, which corresponds to 12.35 thousand nm, is introduced into the furnace through a nozzle with a slit-like outlet, and is fed to the boundary between the sintering and cooling zones with a spread angle & under pressure of 20.0 kg / mf. When a jet of air comes into contact with the material to be calcined, clinker particles with granule sizes of 0.01-5 mm are returned by the air flow to the sintering zone, where they are completely granulated and thus clinker pyenia is reduced. Comparative figures The known and proposed methods for burning cement clinker on a rotary kiln 5x185 m are presented in the table.

Analysis presented in the table. the spirit depends on the content of small clindungs suggests that the kerosene granules in the clinker, the output T is the magnitude of the opening angle of the air stream from the rotary kiln. So, with MinN. pressure, under which the possibility of supplying .65 to the ground is given: the clinker core

Claims (1)

Claim 10 A method of firing cement clinker in a rotary kiln by supplying raw materials from the cold end of the kiln, introducing fuel and air necessary for burning from the hot 15th end, heating That is, in order to reduce clinker dusting and fuel consumption, part of the air is supplied to the interface between the sintering and cooling zones by the jet, with an angle 20 disclosure 30-120 ° under a pressure of 150 350 kg / m ² .