阅读说明：本技术 一种氧化铝熟料钙比的控制方法 (Method for controlling calcium ratio of alumina clinker ) 是由 赵卫 张建业 郭庆山 张海平 张军华 王凯 陈洪德 于 2021-08-03 设计创作，主要内容包括：本发明公开了一种氧化铝熟料钙比的控制方法,采用以下公式进行计算：应送料浆[C/S]＝熟料[C/S]+K1+K2,其中,应送料浆[C/S]为应送料浆中氧化钙与二氧化硅的摩尔比；熟料[C/S]为熟料中氧化钙与二氧化硅的摩尔比；K1＝过去时间内多个班次的料浆[C/S]-对应班次的熟料[C/S]；K2＝(当前料浆[A/S]-过去多个班次的料浆[A/S])*料浆[A/S]影响系数,当前料浆[A/S]为当前料浆中氧化铝与二氧化硅的摩尔比,料浆[A/S]影响系数为料浆中氧化铝与二氧化硅的摩尔比。本发明能够超前指导及有效提高熟料[C/S]的控制精确度、确保熟料钙比达到要求范围。(The invention discloses a method for controlling the calcium ratio of alumina clinker, which adopts the following formula to calculate: the slurry to be sent [ C/S ] + clinker [ C/S ] + K1+ K2, wherein the slurry to be sent [ C/S ] is the molar ratio of calcium oxide to silicon dioxide in the slurry to be sent; the clinker [ C/S ] is the molar ratio of calcium oxide to silicon dioxide in the clinker; k1 ═ slurry [ C/S ] for multiple shifts over time-clinker [ C/S ] for the corresponding shift; k2 ═ slurry [ a/S ] influence factor (current slurry [ a/S ] — (slurries [ a/S ] of past shifts) × slurry [ a/S ], current slurry [ a/S ] being the molar ratio of alumina to silica in the current slurry, slurry [ a/S ] influence factor being the molar ratio of alumina to silica in the slurry. The invention can lead in advance, effectively improve the control accuracy of clinker C/S and ensure that the calcium ratio of the clinker reaches the required range.)

1. The method for controlling the calcium ratio of the alumina clinker is characterized by adopting the following formula for calculation: the slurry to be sent [ C/S ] + clinker [ C/S ] + K1+ K2, wherein the slurry to be sent [ C/S ] is the molar ratio of calcium oxide to silicon dioxide in the slurry to be sent; the clinker [ C/S ] is the molar ratio of calcium oxide to silicon dioxide in the clinker; k1 is slurry [ C/S ] of a plurality of shifts in the past time-clinker [ C/S ] corresponding to the shift, the slurry [ C/S ] of the plurality of shifts in the past time is a molar ratio of calcium oxide to silica in the slurry of the plurality of shifts in the past time, and the clinker [ C/S ] corresponding to the shift is a molar ratio of calcium oxide to silica in the clinker of the corresponding shift; k2 ═ slurry [ a/S ] influence coefficient (current slurry [ a/S ] — (slurry [ a/S ] of a plurality of previous shifts), slurry [ a/S ] influence coefficient, current slurry [ a/S ] is a molar ratio of alumina to silica in current slurry, slurry [ a/S ] of a plurality of previous shifts is a molar ratio of alumina to silica in slurry of a plurality of previous shifts, and slurry [ a/S ] influence coefficient is a molar ratio of alumina to silica in slurry.

2. The method of controlling the calcium ratio of alumina clinker according to claim 1, wherein the K2 value increases or decreases by 0.008 for every 0.1 increase or decrease in the difference between the current slurry [ A/S ] and the slurries [ A/S ] of the past shifts.

3. The method for controlling the calcium ratio of alumina clinker according to claim 2, wherein the absolute values of the difference between the current slurry [ A/S ] and the slurry [ A/S ] of the past shifts are within seven ranges of (0.05 to 0.06), (0.07 to 0.19), (0.20 to 0.32), (0.33 to 0.45), (0.46 to 0.58), (0.59 to 0.71) and ≧ 0.72, respectively, and the K2 values respectively correspond to the positive and negative values of ± 0.005, ± 0.01, ± 0.02, ± 0.03, ± 0.04, ± 0.05, ± 0.06, K2 values and the positive and negative values of the difference between the current slurry [ A/S ] and the slurry [ A/S ] of the past shifts.

4. The method for controlling the calcium ratio of the alumina clinker according to claim 1, characterized in that the method uses an inverted groove [ C/S ] trend to characterize the difference between the actual slurry [ C/S ] and the slurry [ C/S ] to be fed, and when the difference between the actual slurry [ C/S ] and the slurry [ C/S ] to be fed is positive, the inverted groove [ C/S ] trend is upward; when the difference value between the actual feeding slurry [ C/S ] and the slurry [ C/S ] to be fed is negative, the tendency of groove inversion [ C/S ] is downward.

5. The method for controlling the calcium ratio of alumina clinker according to claim 4, wherein the trend of the backset [ C/S ] is consistent with the trend of K2.

Technical Field

The invention belongs to the technical field of metallurgy, and particularly relates to a method for controlling the calcium ratio of alumina clinker.

Background

As a world producing country with the highest alumina yield, the annual Chinese alumina cumulative yield in 2020 exceeds 7000 million tons. In the process of producing alumina by a sintering method, the raw material preparation and the clinker sintering process are the basis and the key of the production of alumina by the sintering method, the clinker calcium ratio is an important index, and whether the clinker calcium ratio is stable or not is directly related to the stable and efficient operation of a clinker sintering and dissolving system. The preparation of the clinker calcium ratio requires that a certain amount of materials such as lime (limestone), bauxite and the like generate expected 2CaO & SiO during sintering₂Therefore, CaO and SiO must be used₂Strictly maintain a certain mixing ratio, i.e. the calcium ratio (or [ C/S ]])。

The clinker calcium ratio is mainly adjusted by controlling the raw slurry calcium ratio. In conventional batching methods, the regulation of the slurry [ C/S ] is typically guided by determining the current slurry [ C/S ] that should be sent out, based on the difference existing between the [ C/S ] of the slurry sent out and the corresponding clinker [ C/S ] over a certain time in the past, namely:

feeding slurry [ C/S ] + clinker [ C/S ] + K1;

wherein: k1 is Δ [ C/S ] is the weighted average of the slurry [ C/S ] over a certain period of time-the corresponding clinker [ C/S ].

K1 in this method is actually a comprehensive representation of the influence of various delta C/S influencing factors under certain conditions in the past certain time. The disadvantages of this control method are: it is assumed that the factors affecting Δ [ C/S ] in the past do not change, and actually, the factors affecting Δ [ C/S ] are dynamically changing. Therefore, in the actual application process of the traditional control method, the problems of quick change of delta C/S, poor representativeness of slurry to be fed [ C/S ], poor timeliness for guiding slurry calcium ratio regulation and control and the like often occur, and the difficulty is brought to the subsequent production process. The control of clinker [ C/S ] is always a difficult point and key point of ingredient production, and the qualification rate of clinker [ C/S ] is only about 75%.

How to provide a rapid, effective and strong-operability clinker calcium ratio regulation and control method, overcoming the defects of large fluctuation range of clinker calcium ratio index, difficult control and the like, and is a problem to be solved urgently in sintering process alumina.

Disclosure of Invention

Aiming at the defects of a clinker [ C/S ] regulation and control method in the prior art by a sintering method, the invention provides a control method of the calcium ratio of alumina clinker in the process of producing alumina by the sintering method, which is vivid, visual and strong in operability, can guide in advance, can effectively improve the control accuracy of the clinker [ C/S ], and can ensure that the calcium ratio of the clinker reaches the required range.

The invention adopts the following technical scheme:

the method for controlling the calcium ratio of the alumina clinker is characterized by adopting the following formula for calculation: the slurry to be sent [ C/S ] + clinker [ C/S ] + K1+ K2, wherein the slurry to be sent [ C/S ] is the molar ratio of calcium oxide to silicon dioxide in the slurry to be sent; the clinker [ C/S ] is the molar ratio of calcium oxide to silicon dioxide in the clinker; k1 is slurry [ C/S ] of a plurality of shifts in the past time-clinker [ C/S ] corresponding to the shift, the slurry [ C/S ] of the plurality of shifts in the past time is a molar ratio of calcium oxide to silica in the slurry of the plurality of shifts in the past time, and the clinker [ C/S ] corresponding to the shift is a molar ratio of calcium oxide to silica in the clinker of the corresponding shift; k2 ═ slurry [ a/S ] influence coefficient (current slurry [ a/S ] — (slurry [ a/S ] of a plurality of previous shifts), slurry [ a/S ] influence coefficient, current slurry [ a/S ] is a molar ratio of alumina to silica in current slurry, slurry [ a/S ] of a plurality of previous shifts is a molar ratio of alumina to silica in slurry of a plurality of previous shifts, and slurry [ a/S ] influence coefficient is a molar ratio of alumina to silica in slurry.

The method for controlling the calcium ratio of alumina clinker is characterized in that the K2 value is increased or decreased by 0.008 every time the difference between the current slurry [ A/S ] and the slurry [ A/S ] of a plurality of past shifts is increased or decreased by 0.1.

The method for controlling the calcium ratio of the alumina clinker is characterized in that when the absolute values of the differences between the current slurry [ A/S ] and the slurries [ A/S ] of the past shifts are in seven intervals of (0.05-0.06), (0.07-0.19), (0.20-0.32), (0.33-0.45), (0.46-0.58), (0.59-0.71) and ≥ 0.72, the K2 values respectively correspond to the positive and negative values of + -0.005, + -0.01, + -0.02, + -0.03, + -0.04, + -0.05, + -0.06 and K2 values, and the positive and negative values of the differences between the current slurry [ A/S ] and the slurries [ A/S ] of the past shifts.

The method for controlling the calcium ratio of the alumina clinker is characterized in that the method adopts a reversed groove [ C/S ] trend to represent the difference value of the real slurry [ C/S ] and the slurry [ C/S ] to be fed, and when the difference value of the real slurry [ C/S ] and the slurry [ C/S ] to be fed is positive, the reversed groove [ C/S ] trend is upward; when the difference value between the actual feeding slurry [ C/S ] and the slurry [ C/S ] to be fed is negative, the tendency of groove inversion [ C/S ] is downward.

The method for controlling the calcium ratio of alumina clinker is characterized in that the trend of the groove inversion [ C/S ] is consistent with the trend of K2.

The invention has the beneficial technical effects that: (1) the invention is suitable for alumina production plants with pure sintering method or sintering method part, and can greatly improve the control level of clinker calcium ratio index. The method of the invention fills a calcium ratio regulation system by introducing the influence coefficient of slurry [ A/S ] on the clinker calcium ratio, comprises the process of regulating the clinker calcium ratio by raw slurry, namely, corrects the slurry [ C/S ] when the raw slurry [ A/S ] changes, and has the characteristics of advanced guidance, strong operability and the like. (2) According to the invention, the slurry [ A/S ], the clinker sintering and the clinker [ C/S ] are organically combined according to the relative change of the poured slurry [ A/S ], and the change trend of the [ C/S ] and the change amplitude of the [ C/S ] are represented by specific quantitative data (an image arrow) in a comparison chart, so that the reasonable slurry [ C/S ] to be fed is determined, and the slurry blending operation is guided, and the effect is obvious. The method not only solves the defect that the fluctuation of the clinker calcium ratio is difficult to analyze in the prior art, but also further quantifies the regulation and control process of the clinker calcium ratio and improves the control accuracy of the clinker calcium ratio. (3) The method of the invention strips the slurry [ A/S ] which can completely master the change trend and amplitude from the influence factors influencing the raw clinker [ C/S ] difference, straightens the internal relation between the [ A/S ] change and the [ C/S ] adjustment, has the characteristics of image, intuition, advanced guidance, strong operability and the like, overcomes the problems of poor representativeness and low regulation efficiency of slurry [ C/S ] to be sent in the prior art, improves the guidance of slurry [ C/S ] to be sent, obviously enhances the control capability of clinker [ C/S ], ensures that the percent of pass of clinker [ C/S ] reaches more than 85 percent for years continuously, and lays a solid foundation for improving the net dissolution rate of clinker kiln and alumina.

Detailed Description

Taking the slurry [ A/S ] (namely the molar ratio of alumina to silicon dioxide in the slurry) as an important basis for adjusting the calcium ratio of the slurry, and establishing a rule for guiding the adjustment of the calcium ratio of the slurry by the change of the slurry [ A/S ], namely quantifying the specific influence coefficient of the slurry [ A/S ] on the calcium ratio of the slurry. The contrast of parameters such as K2 correction trend, groove inversion [ C/S ] trend and the like in a contrast chart is fully utilized, the functions of accurately prejudging and blending the clinker calcium ratio are achieved, and the clinker calcium ratio is ensured to reach the required range.

The control method of the invention is based on the pouring out of slurry [ A/S ]]Relative change of (2) slurry [ A/S ]]Sintering of clinker and clinker [ C/S ]]The three are organically combined, i.e. slurry [ A/S]Is representative of SiO in the slurry₂While in the process of clinker firing, the raw slurry is accompanied by [ A/S ]]The change of (1), the clinker sintering temperature change and the coal consumption change of per ton clinker directly influence delta C/S]Therefore, the slurry [ A/S ] is added based on the original calculation]The correction factor is affected, thereby eliminating the effect of this factor. The method of the invention is to refine the slurry [ A/S ] specifically]On the basis of influence coefficient of slurry calcium ratio, slurry [ A/S ] is adopted]Clinker aggregate [ C/S ]]Slurry [ C/S ]]Sending the slurry [ C/S ]]Correcting the feed [ C/S ]]K2 value, K2 correction trend, groove inversion [ C/S ]]Plotting the parameters such as trend into a comparison chart when raw material is [ A/S ]]While changing to slurry [ C/S ]]Corrected to improve the clinker aggregate C/S]Control accuracy of (1)The control method of the invention overcomes the defect that the prior art has delta C/S]Fast change of clinker aggregate C/S]Large index fluctuation range, difficult control and the like. The method not only has the characteristics of image, intuition, advanced guidance, strong operability and the like, but also ensures the qualification rate of the clinker calcium ratio index.

In the technical scheme of the invention, the calcium ratio is an important technical parameter in the production process of the aluminum oxide, and is the molar ratio of calcium oxide to calcium dioxide. In actual operation, the slurry [ A/S ] is taken as an important basis for adjusting the calcium ratio of the slurry and is expressed by an influence coefficient K2; meanwhile, establishing a rule for guiding the adjustment of the calcium ratio of the slurry by the change of the slurry [ A/S ]; specifically, the 'comparison chart' is used for guiding regulation and control of the calcium ratio of the slurry and analyzing the reason and trend of clinker [ C/S ] change, and correction is carried out according to the change of the slurry [ A/S ], so that the calcium ratio of the clinker is ensured to reach the required range.

In the regulation and control operation of the clinker calcium ratio in the existing production practice, the method comprises the following steps:

feeding slurry [ C/S ] + clinker [ C/S ] + K1;

the factors influencing K1 mainly include clinker sintering degree, coal consumption, burnt coal ash, raw material [ A/S ] change and the like, according to the analysis of the influence factors, slurry [ A/S ] is a predictable influence factor, and the influence of the slurry on the raw clinker [ Delta [ C/S ] is large, so that the slurry [ A/S ] influence correction coefficient is increased on the basis of the calculated sending of the original method as the basic sending (the calculation of the sending includes the comprehensive influence of all the factors in the past), and the influence of the factor is eliminated. According to the idea, the calculation formula of the slurry [ C/S ] to be sent in the method for controlling the calcium ratio of the alumina clinker is determined as follows:

feeding slurry [ C/S ] + clinker [ C/S ] + K1+ K2;

wherein: the [ C/S ] of the slurry to be sent is the molar ratio of calcium oxide to silicon dioxide in the slurry to be sent;

the clinker [ C/S ] is the molar ratio of calcium oxide to silicon dioxide in the clinker;

k1 is slurry [ C/S ] of a plurality of shifts in the past time-clinker [ C/S ] corresponding to the shift, the slurry [ C/S ] of the plurality of shifts in the past time is a molar ratio of calcium oxide to silica in the slurry of the plurality of shifts in the past time, and the clinker [ C/S ] corresponding to the shift is a molar ratio of calcium oxide to silica in the clinker of the corresponding shift;

k2 ═ slurry [ a/S ] influence coefficient (current slurry [ a/S ] — (slurry [ a/S ] of a plurality of previous shifts) × slurry [ a/S ], current slurry [ a/S ] being a molar ratio of alumina to silica in the current slurry, slurry [ a/S ] of a plurality of previous shifts being a molar ratio of alumina to silica in the slurry of a plurality of previous shifts, slurry [ a/S ] influence coefficient being a molar ratio of alumina to silica in the slurry; the influence coefficient of the slurry [ A/S ] is determined to be 0.08 by measuring and calculating the material balance under various conditions.

The K2 is actually the delta C/S change caused by the change of the current slurry [ A/S ] and the slurries [ A/S ] of a plurality of past shifts, the practical summary can calculate the range of the K2 value changing with the slurry [ A/S ], and the determination of the K2 value is actually the determination of the influence coefficient of the slurry [ A/S ] and can be obtained only by a large amount of material balance calculation. After calculation of material balance under various conditions, when the difference value between the current slurry [ A/S ] and the slurry [ A/S ] of a plurality of past shifts increases or decreases by 0.1, the K2 value (namely delta [ C/S ]) increases or decreases by 0.008. Therefore, the influence of the quantized raw material [ A/S ] on the delta [ C/S ] is significant, the influence coefficient which is relatively suitable for the current production can be obtained to be 0.08, through production summary, the [ A/S ] difference value is divided into seven grades, and the [ C/S ] correction value K2(0.005-0.06) under each grade is calculated; when the absolute values of the differences between the current slurry [ A/S ] and the slurries [ A/S ] of a plurality of past shifts are in seven intervals of (0.05-0.06), (0.07-0.19), (0.20-0.32), (0.33-0.45), (0.46-0.58), (0.59-0.71) and ≧ 0.72, the K2 values are respectively plus or minus 0.005, + -0.01, + -0.02, + -0.03, + -0.04, + -0.05, + -0.06 and K2 values, and the plus or minus of the difference between the current slurry [ A/S ] and the slurries [ A/S ] of the plurality of past shifts. The control method adopts the inverse groove [ C/S ] trend to represent the difference value of the real slurry [ C/S ] and the slurry [ C/S ] to be fed, and when the difference value of the real slurry [ C/S ] and the slurry [ C/S ] to be fed is positive, the inverse groove [ C/S ] trend is upward; when the difference value between the actual feeding slurry [ C/S ] and the slurry [ C/S ] to be fed is negative, the tendency of groove inversion [ C/S ] is downward. The tendency of the undercut [ C/S ] is consistent with that of said K2, see for example Table 1.

TABLE 1 Current slurries [ A/S]With the slurry [ A/S ] of past shifts]Difference of (A), K₂Groove inversion [ C/S ]]Relationship between trends

The comparison chart is a table in which parameters such as the difference between the current slurry [ a/S ] and the slurries [ a/S ] of a plurality of past shifts, clinker [ C/S ], slurry to be fed [ C/S ] corrected (i.e., adding a K2 value, slurry to be fed [ C/S ] corrected), a K2 value, a K2 correction trend, and a tank inversion [ C/S ] trend are plotted to represent the respective changes, and specifically, for example, as shown in table 2:

TABLE 2 relationship of the respective parameters when the central value of clinker [ C/S ] is 1.600

The clinker [ C/S ] blending analysis method of the invention actually uses a comparison chart to guide the regulation and control of the clinker [ C/S ] and analyze the reason and the trend of the change of the clinker [ C/S ], and corrects the calcium ratio control process according to the change amplitude of the slurry [ A/S ].

In the specific scheme provided by the invention, the following rules are followed in practical implementation:

1. after each shift, according to the production conditions of the last three shifts (each shift is 8 hours), summarizing the data, filling related data and legends in the table, displaying the trend according to the legends, analyzing and predicting the change condition of clinker [ C/S ] of the next three shifts, and determining the direction of the shift groove [ C/S ] of the shift.

2. In general production, after the K2 trend is determined, the groove to be inverted [ C/S ] can be determined according to the pitching and the angle of the K2 trend arrow, the groove to be inverted [ C/S ] trend is consistent with or similar to the K2 trend, namely the forward operation, and the situation that the groove to be inverted [ C/S ] trend is contrary to the K2 trend is avoided. However, when the index needs to be adjusted urgently, the reverse operation is needed, that is, the inverted groove [ C/S ] trend is contrary to the K2 trend, and the method has great twisting strength to the index and has twice the effect with half the effort. The effect that the [ C/S ] trend of the reversed groove slurry and the K2 trend are in the same direction and opposite directions is flexibly applied by combining the state of the clinker index (namely whether the index belongs to the qualified range).

3. When the [ C/S ] trend of the inverted groove cannot be consistent with the K2 trend due to various condition limitations, the next batch needs to be remedied and adjusted in time.

4. If the trend of the inverted groove slurry [ C/S ] is increased or decreased for more than two shifts (8 hours in each shift), the correction is performed again, and the correction amplitude is gradually decreased, namely, the K2 value is decreased.

To make the objects, technical solutions and advantages of the present invention clearer and more complete, the technical solutions of the present invention will be described below with reference to embodiments, it is obvious that the described embodiments are some, but not all embodiments of the present invention, and all other embodiments obtained by a person of ordinary skill in the art without creative efforts based on the embodiments of the present invention belong to the protection scope of the present invention. The slurry and the clinker adopted in the embodiment of the invention are all taken from aluminum-Zhongzhou aluminum industry Co.

Example 1

The qualified range of clinker aggregate [ C/S ] is 1.57 plus or minus 0.03. 1 shift corresponds to the index of clinker [ C/S ] is already higher and is in an unqualified state; under the premise that the actual feeding slurry [ A/S ] continuously descends, in the subsequent slurry [ C/S ] adjusting process of 2 shifts and 3 shifts, the slurry [ C/S ] is synchronously reduced by combining the principle that the trend of the reversed groove [ C/S ] is consistent with or similar to the trend of K2, and the index of the clinker [ C/S ] is rapidly corrected to reach the qualified range.

Example 2

The qualified range of clinker aggregate [ C/S ] is 1.57 plus or minus 0.03. 1 shift corresponds to the lower index of clinker [ C/S ] and is in an unqualified state; under the condition, on the premise that the actual slurry [ A/S ] is continuously sent to descend, the slurry groove-reversing [ C/S ] trend is contrary to the K2 trend in terms of 2 shifts and 3 shifts, the method has large twisting and correcting force on the indexes, and quickly adjusts the lower clinker [ C/S ] index to be in the qualified range, thereby achieving the effect of twice the result with half the effort.