In the production of glass bottles and cans, the color conversion of materials is a regular work. There are two main methods for color conversion in tank kiln production. First, empty the original colored glass liquid and put in new colored glass batch; The second is to adopt the method of transition replacement. Compared with the two methods, the former method needs to stop production and consume certain human, financial and material resources, and at the same time, protective measures should be taken for equipment such as material channels. Depending on the amount and melting capacity of glass liquid in the kiln, the production time is different, but it takes at least 4 days. The advantage of this method is that it will not produce mixed color glass. The advantage of the latter method is uninterrupted production, which does not need to spend extra money and material resources. However, due to the mixing of two different colored glasses, most manufacturers treat transitional colored glass as waste. Which way is more advantageous depends on the actual situation. Generally speaking, it is not necessary to use the first method to convert colorless glass into colored glass. When the second method is adopted, by appropriately increasing the amount of colorant, the refueling period can be greatly shortened and the generation of transition color glass can be reduced. When colored glass is converted into colorless glass, the first method is needed, mainly because this process lasts for a long time, especially when it is converted into high white material. On the whole, most manufacturers generally adopt the second method. However, how to shorten the refueling time to reduce the transition color glass and complete the color conversion as soon as possible is a topic that many manufacturers are discussing. Taking the transition from green materials to white materials in our company as an example, this paper briefly introduces some of our practices.
1 99810 June 16 Our company1No.1 boiler changed from green material to white material. The general situation of the kiln is as follows:
Melting area: 34 square meters
Capacity (melting rate) at that time:1.1t/m2 * d.
Furnace type: coal-fired horseshoe flame pool kiln.
1 Preparation before refueling
Formula design of 1. 1
According to the set output, production machine speed, product variety characteristics and other factors, the formula of ordinary white material is determined as Table 1, and the original green material formula is shown in Table 2.
Table 1 white material formula
Quartz sand soda ash limestone dolomite fluorite barite sodium nitrate clarifier mica
100 29.8 16.2 5.4 8.2 2.7 1.6 2.4 0.9 5
Table 2 Emerald Formula
Sand soda ash limestone dolomite fluorite barite chromium ore powder clarifier mica
100 30.6 14 1 1 2.7 1.6 1 0.9 7
Calculation of redox index 1.2
The redox NO of this batch is equal to the ratio of various raw materials (relative to 2000 parts of quartz sand) multiplied by the sum of redox coefficients of various raw materials. The redox coefficient proposed by Calumite Company of the United States is shown in Table 3.
Table 3 Table of Redox Coefficient
Oxidation coefficient (1kg/2000kg sand) and reduction coefficient (1kg/2000kg sand).
Sodium sulfate +0.67 carbon (100% carbon) -6.70
There is hydrated gypsum (CaSO4. 2H2O) +0.56 coke (85%C) -5.70
Anhydrous gypsum (CaSO4) +0.70 natural coke (65%C) -4.36
Barite (BaSO4) +0.4 sulfur is uncertain.
Nitrite (NaNO3) +0.32 iron sulfide (FeS)-1.60
Manganese dioxide+1.09 pyrite (FeS2)-1.20
Arsenic oxide (As2O3) +0.93 chromite (FeCrO3)-1.00
Iron oxide (Fe2O3) +0.25 fluorite (CaF2) -0. 10
Sodium dichromate (Na2Cr2O7) +0.77 blast furnace slag -0.073
Potassium dichromate (K2Cr2O7) +0.65 arsenic -0.93
The redox index of ordinary white material is 22.76, and that of emerald material is 7.4. Both of them are oxidizing, and the difference of redox between them need not be considered when refueling.
After the above work is completed, determine the process parameters of the production process.
2 Measures taken in the process of refueling
(1) The dosage of oxidant, decolorant and broken glass should be appropriately increased in the formula of ordinary white material;
(2) Before the white material is put into production, the glass level will be reduced by 4cm on the premise of ensuring normal production, so as to reduce the amount of original emerald glass liquid in the pool furnace and increase the temperature of the material liquid at the lower part of the pool furnace;
(3) After adding the white material, observe the color change of the material. When there is obvious thinning, the melting temperature is increased by 20℃ on the basis of the operating temperature of the green body, and the discharge amount is gradually increased to120% of the original level;
(4) according to the color change of the material, gradually reduce the dosage of the decoloring agent to the normal dosage;
5] When the color is basically normal, restore the melting temperature, glass level and discharge to normal or design level.
3 implementation effect
By taking the above measures, the cycle of changing green materials into ordinary white materials is shortened to less than 9 days compared with the previous half month, and ordinary white glass products can be produced normally. Due to the strict control of the refueling process, there are no defects such as bubbles. The whole refueling process greatly reduced the number of transition color glass products, which won valuable time for enterprises to occupy the market in time and achieved good benefits because of the reduction of transition color products.
Author: (Shandong Rongcheng Huapeng Glass Co., Ltd., Rongcheng 264309)
Calculation of coloring rate of float glass converted into colored glass
Date: 07-22 14:57 Source: Jialong International Glass Purchasing Network
Glass melted by adding colorant to raw materials is called colored glass. Its production has two characteristics: (1) besides checking the quality of colored glass according to ordinary glass standards, it is also necessary to detect and control the consistency, uniformity and reproducibility of color. (2) It is required that the production process can realize the variety conversion of colored glass with minimum production loss. Based on the production practice, this paper puts forward a calculation method of glass coloring rate, which can be used to calculate the relative percentage content of colorant in finished glass in a certain period of time under a given coloring scheme, which is very helpful to guide glass coloring production.
1. Establishment of formula for calculating coloring rate of float glass
On the float glass production line, the conversion production of colored glass mainly adopts "refueling method in production process". This method is: according to the requirements of product color uniformity and good quality, under the condition of not affecting production, the newly composed batch is put into the original glass liquid and gradually replaced, so that the color of glass changes from urban pollution to another color in the shortest time. Generally speaking, it takes about 6~ 14 days for the whole glass bath to be completely transformed into new glass bath. This time is related to the time that the glass liquid stays in the kiln, that is, to the ratio of the total capacity of the glass liquid to the output of the tank kiln; At the same time, it is related to the amount of colorant added. Practice has proved that the speed of glass coloring conversion is not only related to the unique glass flow rate of each kiln, but also depends on the coefficient of excessive mixing of colorants, which is generally 2~3 times the amount of standard colorants. Because changing the adding mechanism of colorant has little effect on the composition of base glass, the coefficient of excessive mixing of colorant can be adjusted in a wide range. The greater the amount of colorant added, the longer the adding time, the faster the colorant content in the finished glass rises and the faster the glass coloring speed. According to many years of production experience, the content Cx of colorant in glass can be expressed by formula.
Cx = T × Co / R(B) / Tr
These include:
T is the coloring time in hours;
Co is the design content of colorant in the finished glass;
R(B) is a coefficient related to the mixing excess coefficient b;
Tr is the ratio of kiln production capacity to off-duty output.
According to the production experience, the relationship between B and R(B) is as follows:
B = 1，R(B)= 2；
B = 2，R(B)= 0.7；
B = 3，R(B)= 0.4；
B = 4，R(B) = 0.3 .
Tr is a ratio, which is equivalent to the average time that the glass liquid stays in the kiln.
For a 400-ton float glass production line, if the total capacity of molten glass in the kiln is 2400 tons, Tr = 2400/400 = 6 days. In addition, if the whole glass kiln contains the same glass colorant component, and the colorant-related components in the finished glass reach Cy at the beginning of coloring, the mixing excess coefficient B, Cx = T × Co/R(B)/Tr+Cy is the formula for estimating the coloring rate of float glass.
2. Application of the formula for estimating the coloring rate of float glass.
Tr = 144 hours, and the glass coloring scheme of the glass tank kiln is as follows: (1) First, the raw material 3Co colorant is added to the kiln with B = 3 for 4 1 hour. (2)B = 2, that is, how many seconds does the relative content of colorant-related components in the finished glass last for 29 hours after the raw material of 2Co colorant enters the kiln?
Can be calculated as follows:
c 1 = t 1×Co/R(b 1)/Tr = 4 1Co/0.4/ 144 = 0.7 1Co
C2 = T2 × Co / R(B2) / Tr + C 1
= 29Co/0.7/ 144+0.7 1Co
= company
T 1+T2 = 4 1+29 = 70 hours.
The results show that the over-mixing coefficient b is between 2 and 3 when the float glass changes from material to color. As long as the color of the glass is close to the design color after 70 hours of coloring, the colorant in the glass raw material should be configured according to the ideal value of Co, otherwise excessively prolonging the over-doping time will be unfavorable to glass production. Many production examples also prove this conclusion.
2. Conclusion
The above formula for estimating the glass coloring rate is an empirical formula, and the result of hard reading is basically the same as that of the junior middle school of glass coloring, which is of great help to estimate the glass coloring degree. Because glass coloring is a complex physical and chemical process, it is influenced by many factors, such as the influence of coloring color of colorant on glass melting itself, the volatility of colorant, the atmosphere of glass melting, whether new stirring technology is adopted in glass melting and so on. If combined with other detection methods, the effect of guiding glass coloring production will be better. For example, the determination of the characteristic monochromatic light transmittance of colored glass or the total transmittance of colored glass can guide the glass coloring production more sensitively. With advanced detection technology and rich working experience, some manufacturers can get the blending excess coefficient B to 5, 10, 15, or even 20,50. But one thing is certain, the bigger B, the shorter the coloring time, so as to avoid too many negative effects.
Refueling method of glass screen cone dual-purpose furnace for color kinescope
The application patent number is CN02 12889 1.7.
Patent application date: August 2002 19
Refueling method of glass screen cone dual-purpose furnace for color kinescope
Release (announcement)No. CN 147707 1
Publication date (announcement) February 25, 2004
Category chemistry; metallurgy
Certification date
right of priority
Apply for (patent right) Henan An Cai Group Co., Ltd.
Address: No.455000, South Section of Zhongzhou Road, Anyang City, Henan Province
Inventor (designer) Li Liuen; Cang limin
International application
International announcement
date of entry
Patent Agency of Electronic Patent Center of Ministry of Information Industry
Agent Li Qinyuan
abstract
The invention relates to a material changing method of a screen cone dual-purpose furnace for color kinescope glass, which belongs to the technical field of glass shell production lines for color kinescope, and comprises the following steps: a. When producing screen glass, the cone material is changed into screen material, and the furnace washing method is adopted. B. When cone glass is to be produced, cone material is used instead of screen material, and the method of forced correction and displacement is adopted. The invention can switch the kiln from producing cone glass to producing screen glass at the fastest speed, the shortest time and the lowest cost in the hot state; Or from the production of screen glass to the production of tapered glass. This oiling process meets the market demand for screen cone products in time.
Sovereignty terms
1. A material changing method for a dual-purpose furnace for glass screen and cone of color kinescope, which includes the switching of screen and cone batch materials, is characterized in that the dual-purpose furnace for screen and cone is carried out according to the following steps: a. When producing screen glass, the cone material is changed into screen material, and the furnace washing method is adopted, that is, the screen glass material is discharged, the furnace is washed with the screen glass material, and then the screen material is added for production; The concrete steps are as follows: (1) discharging old materials and adding new materials, with the taper discharging speed 10 ~ 40 tons/hour; Liquid level: full furnace → bottom; Temperature: 1400- 1600℃ screen feeding speed: 2 ~ 20 tons/hour; Liquid level; Bottom → full furnace; Temperature:1400-1600℃ for 24 hours. (2) discharging furnace washing sieve at the speed of 10 ~ 40t/h; Liquid level: full furnace → bottom; Temperature: 1400- 1600℃, adding sieve into the semi-furnace at a speed of 2-20 tons/hour; Liquid level: bottom → half furnace; Temperature: 1400- 1600℃, and heat preservation for 24 hours. (3) discharging half furnace sieve material and washing the furnace at the speed of 10 ~ 40t/h; Liquid level: half furnace → bottom; Temperature: 1400- 1600℃, screen products can be produced normally by adding screen materials, and the speed is 2 ~ 20 tons/hour; Liquid level: bottom → full furnace; The temperature is 1400 ~ 1600℃. B. When cone glass is to be produced, the screen material is changed into cone material, and the strong correction and displacement oiling method is adopted, that is, a oiling method based on theoretical calculation. The specific steps are as follows: (1) Calculate the residence time of new materials in the pool furnace by using the volume of the pool furnace and the sunrise material quantity; (2) calculating the percentage of new materials flowing out at different times; (3) Set the correction amount when the new material flows out of a certain proportion. The relevant parameters of compulsory correction and displacement refueling are: the volume of pool furnace is 600 tons ~ 800 tons; The output is 190 ~ 300 tons/day.