CN-122010119-A - Quartz sand chlorination purification method

CN122010119ACN 122010119 ACN122010119 ACN 122010119ACN-122010119-A

Abstract

The invention relates to the technical field of quartz sand purification, in particular to a quartz sand chlorination purification method, which comprises the steps of filling quartz sand to be purified into a chlorination reaction furnace, introducing hydrogen chloride gas into the chlorination reaction furnace in a pulse injection mode, identifying temperature abnormal points based on temperature data in a quartz sand layer, judging first-order temperature abnormal reasons of the temperature abnormal points based on historical data of the temperature abnormal points, screening the first-order temperature abnormal reasons based on the change of judging indexes in a preset time window, judging second-order temperature abnormal reasons of the temperature abnormal points, formulating an adjustment strategy according to the second-order temperature abnormal reasons, and optimizing process efficiency on the premise of ensuring reaction safety and product purity so as to realize stable and efficient production of high-quality quartz sand.

Inventors

YIN PEI
HUANG SHAOWEN
SHEN CHEN
JIANG HONGFU

Assignees

湖北鑫阳半导体科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260129

Claims (10)

1. A method for chloridizing and purifying quartz sand, which is characterized by comprising the following steps: s1, quartz sand to be purified is filled into a chlorination reaction furnace; S2, introducing hydrogen chloride gas into the chlorination reaction furnace in a pulse injection mode; s3, identifying temperature abnormal points based on temperature data in the quartz sand layer, and judging first-order temperature abnormality reasons of the temperature abnormal points based on historical data of each temperature abnormal point; s4, screening the first-order temperature abnormality reasons based on the change of the judging index in a preset time window, and judging the second-order temperature abnormality reasons of the temperature abnormal points; S5, formulating an adjusting strategy according to the second-order temperature abnormality reason.
2. The quartz sand chlorination purification method of claim 1, wherein the stock of the furnace tube of the chlorination reaction furnace is 20-30% of the volume of the furnace tube.
3. The quartz sand chlorination purification method of claim 1, wherein the flow rate of the hydrogen chloride gas is 300-400 l/h.
4. The method for chloridizing and purifying quartz sand according to claim 1, wherein the method for obtaining the cause of the first-order temperature anomaly comprises the following steps: s31, acquiring historical temperature data of each temperature abnormal point and surrounding reference points thereof; S32, obtaining characteristic parameters of each temperature abnormal point based on the historical temperature data, wherein the characteristic parameters comprise the historical temperature difference sequence fluctuation intensity of the temperature abnormal point and the energy duty ratio of the frequency spectrum characteristics of the historical temperature data in a preset frequency band; S33, inputting the characteristic parameters into a pre-trained reason classification model to obtain the temperature anomaly reasons of each temperature anomaly point; S34, counting the number proportion of the reason categories judged to be all the temperature abnormal points, and sorting the reason categories in descending order according to the number proportion; S35, judging the first-order temperature anomaly reasons of the temperature anomaly points based on the number proportion of the main suspected reasons and the space distribution rule of the corresponding temperature anomaly points.
5. The quartz sand chlorination purification method of claim 4, wherein the method for obtaining the fluctuation intensity of the historical temperature difference sequence is as follows: S321, acquiring temperature data of the temperature abnormal points and the peripheral reference points in a historical time period to obtain a plurality of historical temperature difference sequences; S322, calculating standard deviation of each historical temperature difference sequence, and taking the average value of a plurality of standard deviations as the fluctuation intensity of the historical temperature difference sequence.
6. The quartz sand chlorination purification method of claim 4, wherein the method for obtaining the energy ratio of the spectral characteristics of the historical temperature data in the preset frequency band is as follows: S32a, carrying out Fourier transform on historical temperature data of each temperature abnormal point to obtain a frequency spectrum; s32b, calculating the ratio of the energy of the frequency spectrum in a preset frequency band to the total energy of the frequency spectrum, namely, the energy duty ratio.
7. The method for purifying quartz sand by chlorination according to claim 4, wherein the first-order temperature abnormality is at least one of the following: (1) If the quantity proportion exceeds a first threshold value and the spatial distribution is irregular, determining that the impurity elements in the quartz sand raw material are unevenly distributed; (2) If the quantity proportion exceeds a second threshold value and the abnormal points are distributed in the downstream of the air inlet or near the furnace wall in a concentrated manner, judging that the flow speed of the hydrogen chloride gas is uneven or the air flow is short-circuited; (3) If the number ratio exceeds a third threshold and the abnormal points are annularly or lamellar distributed around the heating area, determining that the axial or radial temperature gradient in the reaction furnace is out of alignment.
8. The method for chloridizing and purifying quartz sand according to claim 1, wherein the judging indexes comprise a temperature difference sustainability index and a temperature pulse correlation index; the temperature difference persistence index is that in the preset time window, the temperature of the temperature abnormal point is continuously higher than the accumulated time duty ratio of a set threshold value, wherein the set threshold value is a value determined according to the average temperature of the surrounding reference points; The temperature pulse correlation index is a correlation coefficient between a temperature change sequence of temperature abnormal points and a hydrogen chloride gas pulse injection time sequence signal in the preset time window.
9. The quartz sand chlorination purification method of claim 8, wherein the method for calculating the correlation coefficient comprises: S41, sampling the temperature change sequence of the temperature abnormal point at equal time intervals in the preset time window to obtain a first discrete time sequence, synchronously obtaining the hydrogen chloride gas pulse injection state of the corresponding time period, marking the ventilation state as a first value, marking the gas interruption state as a second value, and forming a second discrete time sequence; S42, calculating a cross correlation coefficient of the first discrete time sequence and the second discrete time sequence as the correlation coefficient, wherein a calculation formula of the cross correlation coefficient is a ratio of covariance of the two sequences to products of respective standard deviations.
10. The method according to claim 7, wherein the regulation strategy is to increase the reaction temperature and increase the pulse frequency in case of (1), to decrease the total gas flow and adjust the pulse duty ratio in case of (2), and to adjust the heating power distribution of the reaction furnace and increase the pulse gas preheating temperature in case of (3).

Description

Quartz sand chlorination purification method Technical Field The invention relates to the technical field of quartz sand purification, in particular to a quartz sand chlorination purification method. Background The high-purity quartz sand is used as a key basic material of high-end industries such as semiconductors, photovoltaics, optical fiber communication and the like, and the purity of the high-purity quartz sand directly determines the performance and yield of downstream products. Among them, sodium and other alkali metal impurities are core factors affecting the insulation and thermal stability of quartz sand. The high temperature chlorination purification technology is a main stream technology for removing the impurities, and the principle is that hydrogen chloride gas is introduced at high temperature to convert the impurity elements into volatile chlorides for removal. In the existing chlorination purification process, an operation mode based on fixed process parameters is generally adopted, and basic temperature monitoring is assisted. The common control mode is to arrange a limited thermocouple in the reaction furnace, monitor the whole or partial temperature, and adopt general regulation measures such as reducing the heating power or reducing the gas flow when the temperature exceeds a certain safety threshold. However, this conventional monitoring and control method has significant drawbacks. First, it is generally only able to perceive the appearance of a temperature anomaly, and is not able to diagnose the intrinsic cause of the anomaly. Local fluctuations or increases in the temperature field within the reactor may be caused by various factors such as uneven impurity distribution of the quartz sand feedstock itself, uneven distribution of hydrogen chloride gas in the charge layer to form channeling, uneven thermal field of the heating system itself, or mismatch of the pulse inlet parameters with the current reaction state. Different root causes, in fact, require distinct regulatory strategies. The prior art is often blind and extensive in control actions due to lack of deep diagnostic capabilities for the cause of the anomaly. For example, the system may simply perform a single operation of cooling or downflowing the gas, whether the anomaly is caused by a raw material imbalance or a gas flow imbalance. The regulation mode may not only effectively eliminate the real risk point, but also excessively inhibit the reaction efficiency of the normal area, so that the production efficiency is reduced, the energy consumption is increased, and even new unstable factors are caused by misregulation. In addition, the alarm mechanism of the instantaneous temperature exceeding the threshold value is only relied on, so that the abnormality of short fluctuation and continuous deterioration cannot be distinguished, false alarm or missing alarm is easily caused, and the consistency of the safety and the product quality of the production process is difficult to be accurately ensured. The information disclosed in this background section is only for enhancement of understanding of the general background of the disclosure and is not to be taken as an admission or any form of suggestion that this information forms the prior art that is well known to a person skilled in the art. Disclosure of Invention The invention provides a quartz sand chlorination purification method, which can accurately distinguish the property and the severity of temperature abnormality and generate a regulation and control instruction, so that the process efficiency is optimized and the stable and efficient production of high-quality quartz sand is realized on the premise of ensuring the reaction safety and the product purity. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a quartz sand chlorination purification method comprises the following steps: s1, quartz sand to be purified is filled into a chlorination reaction furnace; s2, introducing hydrogen chloride gas into the chlorination reaction furnace in a pulse injection mode; s3, identifying temperature abnormal points based on temperature data in the quartz sand layer, and judging first-order temperature abnormality reasons of the temperature abnormal points based on historical data of each temperature abnormal point; s4, screening the first-order temperature abnormality reasons based on the change of the judging index in a preset time window, and judging the second-order temperature abnormality reasons of the temperature abnormal points; S5, formulating an adjusting strategy according to the second-order temperature abnormality reason. Further, the stock quantity of the furnace tube of the chlorination reaction furnace is 20-30% of the volume of the furnace tube. Further, the flow rate of the hydrogen chloride gas is 300-400L/h. Further, the method for acquiring the first-order temperature abnormality cause comprises the following st