RU2079459C1 - Method of controlling process of producing cement - Google Patents

Abstract

FIELD: manufacture of building materials. SUBSTANCE: process including feeding and grinding raw materials, firing and grinding obtained clinker with additives, measuring and stabilizing process parameters in each stage, grinding of raw materials is conducted in discrete- continuous mode. In this case, components are fed successively in accordance with calculated time, outgoing parameters of obtained sludge are measured and, when any is deviated from predetermined one, amount of component feed and/or its grinding time are varied. Obtained sludge is agitated and fired also in discrete-continuous mode. Thereafter, parameters of obtained clinker are measured and, when deviated from predetermined ones, amount of sludge and/or sludge feeding time are adjusted until required parameters are obtained. Clinker simultaneously with additives enters discrete-continuous-type cement grinder, outgoing parameters of obtained cement are determined and adjusted to required ones by varying amount of fed clinker or additives and/or grinding time. EFFECT: enhanced efficiency of process. 1 dwg

Description

 The invention relates to the construction materials industry and can be used in cement and other industries.

A known method of producing cement, including grinding raw materials, firing and grinding the resulting clinker [1]
The disadvantages of this method include significant energy costs.

The closest in its technical essence is a method of controlling the process of obtaining cement, including the supply and grinding of raw materials, firing and grinding of the resulting clinker with additives in a cement mill, measuring and stabilizing technological parameters at a certain stage of cement production [2]
The disadvantage of this method is the lack of stability and controllability of the production of materials and high specific energy consumption.

 The objective of the invention is to reduce specific energy consumption, stabilize the properties of the final product, increase the stability and controllability of the technology.

 The problem is solved in that in a method for controlling the process of producing cement, including the supply and grinding of raw materials, firing and grinding of the obtained clinker with additives, measuring technological parameters at each stage of processing and measuring them to specified parameters, grinding of raw materials is carried out in discrete-continuous mode while the supply of components is carried out sequentially in accordance with a certain calculation time, the output parameters of the resulting slurry are measured and if any value deviates from the amount of the supplied component and / or the time of its grinding is measured, the resulting slurry is sent to mixing and subsequent firing, which is also carried out in discrete-continuous mode, then the parameters of the clinker obtained are measured and, when they deviate from the set ones, the quantity and / or time of the supplied slurry is adjusted to obtaining the specified parameters of the clinker, which simultaneously with the additives enters the cement mill of discrete-continuous action, the output parameters of the obtained cement are measured and changed for setpoint quantity supplied to the grinding of clinker or additives and / or time of grinding.

 In the method under consideration, discretely-continuously means that the supply and unloading of material is interrupted while the process is continuous, i.e. combines a batch process when the supply and discharge are closed, and continuous when the supply and discharge are open, etc. Adjustable parameters can be the activity of the finished product, saturation coefficient, grinding fineness, material composition, ratio of the hard-to-grind component.

 In FIG. 1 shows a diagram of an installation that implements a method for controlling the process of producing cement.

 The scheme includes storage bins for crushed raw materials 1, clay baler 2, ten gates 3, measuring containers for raw materials (limestone, cinder and clay sludge) 4, a discrete-continuous continuous feed mill 5, a rotary kiln 6 with a discrete feed through a feed 11 sludge, clinker refrigerator 7, storage bins for clinker and gypsum 8, measuring tanks for clinker and gypsum 9 and cement mill 10 are also discrete-continuous.

 The method is as follows.

 The quantity of materials supplied to the raw material mill and the grinding time are determined on the basis of preliminary control and analysis of the materials taken at the inlet to the storage bins 1 and the clay bale 2. Measured containers are filled after the gates 3 are opened at their inlet, and the amount of materials is determined by the level sensors of these containers (on not shown). The grinding time of raw materials in discrete-continuous mode, determined in advance, is controlled by the order of opening by the shutter 3 at the output of the measuring tanks.

 The furnace 6 is fed with slurry in a discrete-continuous mode with the ability to control the quantity and discreteness of the supplied material through feeders 11, after monitoring and analysis of the sludge at the inlet to the furnace.

 The clinker after the refrigerator 7 and gypsum are fed into the storage bins 8, and the clinker is subjected to control and analysis to determine the grinding time, the amount of material supplied and the discrete characteristics of its supply to the cement mill 10. The feed is carried out from the measuring tanks 9 after opening the shutters 3 at their outlet .

 Example 1 of the implementation of the method for producing cement.

On the basis of preliminary control and analysis of the raw materials fed to the storage bins 1 and the clay baler 2, the ratio and quantity of materials fed to the measuring tanks 4 are determined in such a way as to ensure the required saturation coefficient of the KH and its maximum deviations from the nominal value of the sludge entering the furnace. This coefficient is experimentally determined from samples of sludge, which are taken at the entrance to the furnace. If it is revealed that the SC decreases and falls outside the specified limits, then filling the next portion of the raw materials is performed with some increase, for example, the amount of limestone in the measuring tank 4, which is determined by the operation of the level sensor located above the nominal. In this case, the KN coefficient returns to normal. So, if with a design value of KH 0.92 and a maximum maximum value of KH 0.85, the coefficient values are outside the established limits, then the amount of limestone supplied in the next portion should be increased by 5%
In the process of sludge firing in the furnace, clinker is regularly monitored at the outlet of the clinker refrigerator 7 and, when the KH value deviates beyond the permissible limits up or down, they increase the discreteness of the feed to the furnace 6, i.e. feed material at large time intervals.

 In this case, the selective dust removal from the furnace decreases and the deviation of the SC from the norm decreases, i.e. the firing process is stabilized.

 When grinding the clinker, the fineness of cement grinding is controlled, and if the value of this indicator deviates from the set value, for example, when the cement residue on the sieve No. 008 increases to a value of more than 15%, the time spent by the material in the mill is increased by changing the time for emptying the measuring tanks with clinker and gypsum.

 Example 2

Raw materials are supplied through a measuring tank to a raw mill, the ratios of clay and carbonate material, grinding time are determined in advance to ensure fineness of grinding, i.e. the ratio of clay to carbonate is equal to G K, the grinding time τ _ISM specified fineness of grinding - R ₀₀₈ . Material feeding and unloading is not carried out, after the grinding time τ _ISM , the supply and unloading is opened and the grinding fineness is measured, it has increased and is equal to R ₀₀₈ , the grinding time τ _{ISM is} increased and the process continues with these parameters.

При помоле клинкера за регулируемый параметр выбирают соотношение твердоразмалываемого компонента (Т) к легкоразмалываемому (Л) и задают его равным на выходе, т.е. Т Л А, время помола при этом равно τ_пом Если после измерения на выходе это соотношение (твердоразмалываемого к легкоразмалываемому) изменилось увеличилось, то увеличивают

и подачу легкоразмалываемого компонента (Л) для получения заданных параметров.After mixing, the sludge from the mill enters the rotary kiln, and the granulometric composition (granule size) of the clinker is selected as an adjustable parameter, the output of which is equal to D _cells , the time of the sludge supply to the furnace is τ _under if it is revealed after measurement that the particle size distribution has increased ( decreased), then reduce (increase) the time of filing sludge

When grinding clinker for an adjustable parameter, the ratio of the hard-to-grind component (T) to the easy to grind (L) is selected and set equal to the output, i.e. T L A, the grinding time is equal to τ _pom. If, after measuring the output, this ratio (hard-to-grind) has increased, then increase

and supplying an easily milled component (L) to obtain predetermined parameters.

 The method allows you to control the process of obtaining building materials based on the control and stabilization of the properties of the intermediate and final product at three main stages, which provides stability and flexibility for controlling all processes and devices and, ultimately, significantly reduces the specific energy consumption in the production of building materials.

Claims (1)

 A method of controlling the process of obtaining cement, including the supply and grinding of raw materials, firing and grinding of clinker with additives in a cement mill, measuring technological parameters at a certain stage of cement production, comparing the measured parameters with the given ones and changing them according to the comparison results, characterized in that the grinding raw materials are in discrete-continuous mode, while the supply of components is carried out sequentially in accordance with a certain calculation time, measured in the initial parameters of the obtained sludge and when a deviation of a value from a given value changes the amount of the supplied component and / or the time of its grinding, the resulting slurry is mixed and sent to firing, which is carried out in discrete-continuous mode, the parameters of the resulting clinker are measured at the output and when the values deviate and / or the time of the supplied sludge is controlled from the set ones to obtain the specified parameters of the clinker, which then simultaneously with the additives enters the discrete-continuous cement mill I, output values obtained cement parameter measured and changed to predetermined values quantity supplied to the grinding of clinker or additives and / or time of grinding.