CN114249522A

CN114249522A - Glass melting furnace

Info

Publication number: CN114249522A
Application number: CN202011019152.8A
Authority: CN
Inventors: 凡思军; 陈树彬; 胡丽丽; 钱敏; 唐景平; 裴广庆; 倪加川; 薛天锋
Original assignee: Shanghai Institute of Optics and Fine Mechanics of CAS
Current assignee: Shanghai Institute of Optics and Fine Mechanics of CAS
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2022-03-29

Abstract

A glass melting furnace adopts induction heating, cooling water is introduced into a furnace wall and a furnace bottom, a layer of glass solidified shell is formed on the furnace wall and the furnace bottom, so that the furnace wall and the furnace bottom are not in direct contact with molten glass, the service life of the furnace is prolonged, and the glass quality is improved. The melting furnace is assembled by stainless steel sleeves, and is simple to install. The melting furnace adopts a bottom leakage mode, the glass leakage adopts a leakage device of a coil pipe cooling closing and an induction heating opening freeze-thaw valve, and the change of the glass flow direction caused by glass drawing is avoided. The stainless steel sleeves at the lower end of the smelting furnace are insulated and arranged on the refractory concrete base, so that the magnetic permeability of induction heating is enhanced. The glass melting furnace can realize continuous production of high-purity glass and high-level radioactive waste liquid glass solidification, is simple and controllable to operate, has long service life, and is not easy to introduce impurities in the melting process, thereby improving the glass quality.

Description

Glass melting furnace

Technical Field

The invention relates to a glass melting furnace, in particular to a high-purity glass and high-level radioactive waste liquid solidified glass melting furnace.

Background

The traditional glass production technology is that glass batch materials are usually added into a Joule heating ceramic tank furnace, the batch materials are heated and melted by adopting electric heating, gas heating and the like, and glass products are formed after clarification and molding. With the development of science and technology, the quality of glass materials is required to be higher and higher, and the quality of glass is closely related to the content of impurities in the glass. During the melting of glass, the bath furnace refractory enters the glass as an impurity by the attack of the high temperature glass melt, adversely affecting the properties of the glass material (e.g., the attack of the refractory causes increased optical loss of the laser glass). Therefore, solving the problem of refractory erosion of the glass melting furnace is a key link for further improving the glass performance.

The glass curing process of the Joule heating ceramic furnace is an important spent fuel post-treatment high-level emission waste liquid curing technology and is industrially applied in the United states, Russia, Germany and Japan. Its advantage is high output rate of glass in unit time. The joule heated ceramic furnace glass curing technology evolved from commercial glass production technology with the disadvantage of limited glass furnace life due to erosion of refractory materials. On the other hand, in order to increase the glass yield, the volume of the joule heating ceramic furnace is large, so that the decommissioning is difficult due to more decommissioned wastes.

In order to solve the problems that the service life of a smelting furnace is short and the performance of glass is influenced due to corrosion of refractory materials in the glass smelting process, scientists inspire a cold crucible high-purity metal smelting technology, and apply the cold crucible technology to high-level radioactive waste liquid glass solidification and high-purity glass production. The cold crucible technology adopts high-frequency induction heating to heat glass materials in a split metal crucible, cooling water is introduced into crucible splits to keep the temperature of the crucible wall at 100-200 ℃, a layer of glass skull with the thickness of 5-10mm is formed on the crucible wall, and the metal crucible wall is not in direct contact with molten glass under the protection of the skull, so that the corrosion resistance of the crucible is enhanced, and the service life of the crucible is prolonged. Because the glass is not corroded by refractory materials, the glass keeps the original components, and has more excellent performance.

French atomic energy Commission US6996153/CN1628233A discloses an induction heating cold crucible, wherein the crucible is divided into arc plates, a cooling loop is formed by drilling holes in the middle of the arc plates, and the processing and installation process is complex. And the arc-shaped plate is easy to generate tip voltage and local overheating, although the patent proposes measures such as edge rounding, arc-shaped plate surface insulation spraying and the like, under the action of a high-frequency power supply, the risk of generating electric arc and local overheating is higher compared with a round tube cold crucible.

Russian patent RU2392675C1 discloses an induction heating cold crucible melting device, and the crucible valving adopts nonrust steel pipe, and a plurality of nonrust steel pipes are a set of to water cooling ring about being equipped with, go up the water cooling ring and be equipped with into outlet conduit, lower water cooling ring switches on the cooling water route. The bottom of the crucible in the design is welded by stainless steel, and all the lobes are not insulated, so that the electromagnetic induction loss is large.

US20160091249a1 discloses an induction heating cold crucible, wherein the crucible is divided into sections by stainless steel tubes, the bottom leakage is made by a gate valve, and the leakage rate is realized by controlling the pressure of the melting furnace. This design is prone to glass spillage when the gate valve is closed and it is difficult to control the glass flow rate and direction.

Chinese patent CN 205048973U discloses a cold crucible device, wherein the crucible is divided into segments by stainless steel tubes, and the cold crucible is designed with an upper water cooling ring and a lower water cooling ring, wherein the lower water cooling ring is a group of 3 steel tubes, the communication is water inlet, and the adjacent 3 steel tubes are communicated to be water outlet. The water cooling ring design has larger electromagnetic induction loss because insulation measures are not adopted among all the petals. On the other hand, the hard connecting part between the tubes is a stainless steel tube, the soft connecting part is a PVC tube, and when the cold crucible is used for high-level liquid waste glass solidification, the PVC tube is easy to age after being irradiated by radioactivity, so that the service life of the crucible is influenced.

Chinese patent CN 106123588A discloses a cold crucible high-temperature melt discharge apparatus, the discharge tube is designed into a whole set of tubular form, the intermediate frequency induction coil is wound outside the discharge tube, this design is that whole discharge tube is all blocked up by solid-state glass when the discharge tube is closed, when restarting, it takes time to melt the glass of whole discharge tube to lead to discharging, and when restarting the discharge tube, it forms the glass wire drawing at the gate easily, the influence is unloaded to flow direction. The discharge tube stretches into the crucible for 2cm, which is not beneficial to discharge the precious metal deposited at the bottom when the high-level waste liquid glass is solidified.

Disclosure of Invention

The invention aims to solve the technical problem of providing a glass melting furnace, which is suitable for the fields of high-purity glass production and high-level nuclear waste glass solidification. The glass melting furnace adopts induction heating, and the furnace body does not directly contact with molten glass, so that the service life of the furnace is prolonged, and the glass quality is improved. The smelting furnace is assembled by stainless steel sleeves, and is simple to install. The glass leakage adopts the leakage device of the freezing and thawing valve which is cooled and closed by the coil pipe and is started by induction heating, thereby avoiding the change of the glass flow direction caused by glass drawing. The stainless steel pipes at the lower end of the smelting furnace are insulated and are arranged on the refractory concrete base, so that the magnetic permeability of induction heating is enhanced. The glass melting furnace can realize continuous production of high-purity glass and high-level radioactive waste liquid glass solidification, is simple and controllable to operate, has long service life, is low in production cost, and can improve the quality of the high-purity glass.

The technical scheme adopted by the invention is as follows:

a glass melting furnace comprises a furnace body and a refractory concrete base with supporting legs, wherein the furnace body is fixed on the base through a screw rod, the top of the furnace body is provided with a furnace cover, and the bottom of the furnace body is provided with a furnace bottom; the furnace cover is also provided with a liquid level measuring port, a window, a tail gas discharge port, a temperature measuring port and a charging port;

the furnace body is a cylinder formed by a plurality of stainless steel sleeves in a surrounding mode, the top surface and the bottom surface of the furnace body are formed by welding an upper circular ring water outlet distribution ring and a lower circular ring water inlet distribution ring, each stainless steel sleeve comprises an inner pipe, an outer pipe sleeved outside the inner pipe and a cover plate covering the bottom of the outer pipe, the inner pipe and the outer pipe are connected through a support, a water outlet is formed in the upper end of the inner pipe, and a water inlet is formed in the upper end of the outer pipe;

the furnace bottom is in a split radial shape, the central angle corresponding to each split is 30-45 degrees, the length of a split slot is 1/2-2/3 of the radius of the furnace bottom, gaps among the splits are filled with aluminate refractory cement, each split is provided with a bubbler, a water cooling tank is welded below each split, the water cooling tank is internally divided into an outer water inlet tank and an inner water outlet tank by a metal plate, the volume of the water inlet tank is smaller than that of the water outlet tank, and the water inlet tank and the water outlet tank are respectively provided with a water inlet pipe and a water outlet pipe; the center of the furnace bottom is provided with a material leaking hole, and a conical freezing and thawing valve mounting interface is welded on the furnace bottom and is used for connecting the freezing and thawing valve;

the cooling water in the frame type stirrer flows from top to bottom through water inlet pipelines at two sides of the stirring rod, the stirring frames at two sides are folded and then flow out after upwards passing through a central pipeline of the stirring rod;

the base is internally provided with a mounting groove of the furnace body, the furnace bottom is mounted on the mounting groove, and the mounting groove and the furnace bottom are insulated by an insulating mica sheet; the furnace body is arranged on the furnace bottom, the upper end of the frame type stirrer is arranged in a stirrer mounting hole in the center of the furnace cover, and the upper end of the freeze-thaw valve is aligned with the material leaking hole and arranged below the base; the furnace cover is covered on the furnace body through the furnace cover buckle and the installation buckle of the upper circular ring water outlet distribution ring, so that the stainless steel metal ball is arranged above the material leakage hole at the bottom of the furnace, and the symmetrical shaft of the frame type stirrer, the spherical center of the stainless steel metal ball, the center of the material leakage hole and the symmetrical shaft of the freeze-thaw valve are on the same straight line.

The upper circular ring water outlet distribution ring and the lower circular ring water inlet distribution ring are divided into N partitions by partition plates, the value range of N is 8-16, N stainless steel sleeves are communicated in each partition, the value range of N is 6-8, and gaps between adjacent stainless steel sleeves are filled with mica sheets for insulation; the distance between the upper circular ring water outlet distribution ring and the lower circular ring water inlet distribution ring is 1-3cm, and the effective volume in the cavity of the upper circular ring water outlet distribution ring is larger than the effective volume in the cavity of the lower circular ring water inlet distribution ring.

The upper circular ring water outlet distribution ring is formed by welding a top cover, an outer side plate, a bottom plate and an inner side plate, is divided into N partitions by a partition plate, a water outlet pipe and a pressure relief safety valve are arranged on the outer side plate of each partition, a stainless steel sleeve inner pipe welding opening is arranged on the bottom plate, and two mounting buckles are arranged on the outer side plate of the upper circular ring water outlet distribution ring;

lower ring water inlet distribution ring form by roof, outer panel, bottom plate and interior plate welding, divide into a N by the baffle and cut off, the welding has an inlet tube on the outer panel of every partition the bottom plate on have stainless steel sleeve outer tube welding opening the roof on have stainless steel sleeve inner tube welding opening, the intraductal cooling water flow of stainless steel sleeve is to being: enters the outer pipe through the water inlet, turns downwards along the outer pipe, turns over the cover plate, turns upwards along the inner pipe and flows out of the water outlet.

The freeze-thaw valve is made of NiCrFe alloy or platinum, the freeze-thaw valve is water-cooled or air-cooled by a spiral pipe with a rectangular cross section, a medium-frequency induction coil is used for heating, an inner conical surface of an upper end interface of the freeze-thaw valve is matched with a conical interface of a furnace bottom, and the freeze-thaw valve is installed in a manner of bolt tightening lug installation or thread tightening installation:

when the freeze-thaw valve is in a threaded fastening installation mode, the threaded interface at the upper end of the freeze-thaw valve is screwed into the threaded hole of the furnace bottom, and the inner conical surface of the threaded interface of the freeze-thaw valve is tightly attached to the outer conical surface of the conical interface of the furnace bottom by screwing the octagonal nut;

when the freeze-thaw valve is in a bolt tightening lug installation mode, 3 installation lugs are welded at a conical connector at the upper end of the freeze-thaw valve, 3L-shaped stainless steel blocks are welded on the furnace bottom, threaded holes are formed in the L-shaped stainless steel blocks, and tightening bolts are installed in the threaded holes.

The diameter of the stainless steel metal ball at the lower end of the frame type stirrer is 30-50 mm.

The stainless steel sleeve is characterized in that the diameter of an inner pipe of the stainless steel sleeve is 8-18 mm, the wall thickness of the inner pipe is 1-2 mm, the diameter of an outer pipe is 16-30 mm, and the wall thickness of the outer pipe is 2-5 mm.

Gaps between adjacent split stainless steel sleeves of the furnace body 2 are 1-2 mm, and mica sheets are filled in the gaps for insulation.

The bubblers are positioned on the same circumference with the center of the furnace bottom 5 as the center of a circle.

The distance between the water cooling box and the center of the circle of the furnace bottom is 1/3-1/2 of the radius of the furnace bottom.

The thickness of the furnace bottom is 3-4 cm, the diameter of the upper end of the central material leaking hole is 20-30 mm, the diameter is reduced downwards at an angle of 10-15 degrees, and a conical material leaking connector is welded at the furnace bottom and is also reduced downwards at an angle of 10-15 degrees.

The thickness of the insulating mica sheet between the furnace body installation groove and the furnace bottom is 3-5 mm.

The invention has the beneficial effects that:

1) the glass melting furnace body is formed by welding a stainless steel sleeve, an upper circular ring water outlet distribution ring and a lower circular ring water inlet distribution ring, the furnace body is arranged on a refractory cement concrete slab, and the glass melting furnace is firm in structure and simple in installation process. The upper circular ring water outlet distribution ring is provided with a pressure relief valve, so that the risk of overpressure of the upper circular ring water outlet ring caused by overhigh water outlet temperature is eliminated.

2) The lower part of the adjacent stainless steel sleeve forming the furnace body, the furnace body and the furnace bottom are insulated by mica sheets, so that the electromagnetic induction loss is reduced.

3) The stainless steel ball of the frame type stirrer is used as a glass leakage mode combining a plug valve and a freeze-thaw valve, so that the flow rate and the flow direction of glass can be conveniently controlled, and the noble metal deposited at the bottom of the furnace can be discharged. The air-cooled or water-cooled coil pipe with the rectangular cross section is adopted to cool the freeze-thaw valve, so that the heat exchange efficiency is increased, the glass in the freeze-thaw valve is quickly solidified, and the closing time of the freeze-thaw valve is reduced. The freeze-thaw valve is tightly installed by adopting threads or bolts, so that the freeze-thaw valve is convenient to install and maintain.

Drawings

FIG. 1 is a schematic view of the structure of a glass melting furnace according to the present invention

FIG. 2 is a schematic view of the lid structure of a glass melting furnace

FIG. 3 is a sectional view of a cover of a glass melting furnace

FIG. 4 is a schematic view of an upper ring cooling water outlet distribution ring structure

FIG. 5 is a sectional view of the upper ring cooling water outlet distribution ring

FIG. 6 is a schematic view of a lower ring cooling water inlet distribution ring structure

FIG. 7 is a cross-sectional view of the lower ring cooling water inlet distribution ring

FIG. 8 is a schematic view of the split stainless steel sleeve structure of the furnace body. FIG. 8A is a schematic view of the upper part of a stainless steel casing and FIG. 8B is a schematic view of the lower part of the stainless steel casing

FIG. 9 is a schematic view showing the flow of cooling water inside a stainless steel sleeve

FIG. 10 is a schematic view of the installation of the stainless steel sleeve and the upper and lower ring cooling water outlet and inlet distribution rings

FIG. 11 is a schematic view of the hearth structure

FIG. 12 is a sectional view of the furnace bottom

FIG. 13 is a schematic view of furnace and furnace bottom installation

Fig. 14 is a schematic view of freeze/thaw valve installation example 1. Fig. 14A is a schematic view of a furnace bottom structure of a freeze-thaw valve installation embodiment 1, fig. 14B is a schematic view of a freeze-thaw valve installation embodiment 1, and fig. 14C is a schematic view of an installation process of the freeze-thaw valve installation embodiment 1

Fig. 15 is a schematic view of freeze/thaw valve installation example 2. FIG. 15A is a schematic view of a furnace bottom structure of freeze-thaw valve installation example 2, FIG. 15B is a schematic view of a freeze-thaw valve installation example 2, and FIG. 15C is a schematic view of an installation process of installation example 1

FIG. 16 is a schematic view of the structure of a frame stirrer

FIG. 17 is a sectional view of the glass melting furnace after completion of the installation thereof

Detailed Description

The invention is further described with reference to the following drawings and detailed description:

referring to the figure 1, the glass melting furnace comprises a furnace cover 10, a furnace body 2, a furnace bottom 5, a frame type stirrer 9, a freeze-thaw valve 62 and a refractory concrete base 7, wherein the furnace cover 10, the furnace body 2, the furnace bottom 5 and the frame type stirrer 9 with stainless steel balls 74 are made of stainless steel 304 or 316, and glass materials in the furnace body 2 are heated by an induction coil 3 with copper bars 6. The glass melting furnace 1 is fixed on a refractory concrete base 7 with supporting legs 8 through a screw rod 4,

referring to fig. 2 and fig. 3, the furnace cover 10 is a cavity structure, a cooling channel 25 with a rectangular section is welded in the cavity, an air inlet 16 and an air outlet 19 of the cooling channel 25 are arranged on the furnace cover, a stirrer mounting port 24 is arranged at the center of the furnace cover 10, a liquid level measuring port 17, a window 18, a tail gas discharge port 21, a temperature measuring port 22 and a feeding port 23 are further arranged on the furnace cover 10, and a buckle 20 mounted with the furnace body 2 is arranged on the outer side wall of the furnace cover 10;

the furnace body 2 is a cylinder formed by welding stainless steel sleeves 14 through an upper circular ring water outlet distribution ring 12 and a lower circular ring water inlet distribution ring 13, each stainless steel sleeve 14 (see figures 8A and 8B) comprises an inner pipe 43, an outer pipe 42 and a cover plate 47, the inner pipe 43 and the outer pipe 42 are connected through a support 44, the bottom end of the inner pipe is covered by the cover plate 47, the upper end of the inner pipe 43 is provided with a water outlet 45, the upper end of the outer pipe 42 is provided with a water inlet 46, the upper circular ring water outlet distribution ring 12 and the lower circular ring water inlet distribution ring 13 are divided into N partitions by partition plates, the value range of N is 8-16, N stainless steel sleeves 14 are communicated in each partition, the value range of N is 6-8, gaps between adjacent stainless steel sleeves 14 are filled with mica sheets for insulation, the upper parts of the stainless steel sleeves 14 are welded on the upper circular ring water outlet distribution ring 12 and the lower circular ring water inlet distribution ring 13, a certain distance of 1-3cm is reserved between the upper circular ring water outlet distribution ring 12 and the lower circular ring water inlet distribution ring 13, and the effective volume in the cavity of the upper circular ring water outlet distribution ring 12 is larger than the effective volume in the cavity of the lower circular ring water inlet distribution ring 13;

the upper circular ring water outlet distribution ring 12 is formed by welding a top cover 29, an outer side plate 30, a bottom plate 31 and an inner side plate 32 (see fig. 4 and 5), the upper circular ring water outlet distribution ring is divided into N partitions by partition plates (33), the partitions communicate N stainless steel sleeves 14, a water outlet pipe 26 and a pressure relief safety valve 27 are installed on the outer side plate 30 of the partitions, a stainless steel sleeve inner pipe welding opening 28 is formed in the bottom plate 31, and two installation buckles 11 are installed on the outer side plate of the upper circular ring water outlet distribution ring 12;

referring to fig. 6 and 7, the lower circular ring water inlet distribution ring 13 is formed by welding a top plate 40, an outer side plate 39, a bottom plate 38 and an inner side plate 37, and is divided into N partitions by a partition plate (41), N stainless steel sleeves 14 of each partition are communicated, a water inlet pipe 36 is welded on the outer side plate 39 of each partition, a stainless steel sleeve outer pipe welding opening 35 is arranged on the bottom plate 38, a stainless steel sleeve inner pipe welding opening 34 is arranged on the top plate 40, and the flow direction of cooling water in the stainless steel sleeves 14 is as follows: enters the outer pipe 42 through the water inlet 46, goes down along the outer pipe 42, is folded by the cover plate 47, goes up along the inner pipe 43, and flows out of the water outlet 45, as shown in fig. 8 and 9;

referring to fig. 10, the stainless steel sleeves 14 are welded and fixed through the inner pipe welding openings 28 shown in fig. 4, the inner pipe welding openings 34 shown in fig. 6 and the outer pipe welding openings 35, and the gap between adjacent stainless steel sleeves 14 is 1.5 mm;

referring to fig. 11 and 12, the furnace bottom 5 has a split 48 structure, the central angle corresponding to each split is 40 °, and the length of the split slit 52 is 3/5 of the radius of the furnace bottom. The petals 48 are provided with bubblers 49, and the bubbler 49 on each petal is on the circumference of the circle with the center of the furnace bottom 5 as the center. A material leaking hole 50 is formed in the center of the furnace bottom, the hole is conical, the diameter of the upper end of the hole is 30mm, the hole is downwards reduced at an angle of 15 degrees, a conical connector 51 is welded on the furnace bottom, and the connector is also downwards reduced at an angle of 15 degrees;

referring to fig. 12, a water cooling tank 57 is welded below the furnace bottom segment 48, a metal plate 55 is arranged in the water cooling tank 57 to divide the water cooling tank into a water inlet tank 58 and a water outlet tank 59, and the volume of the water inlet tank 58 is smaller than that of the water outlet tank 59. The inlet tank 58 and the outlet tank 59 are respectively provided with an inlet pipe 53 and an outlet pipe 54. The distance between the water cooling tank 57 and the center of the furnace bottom is 2/5 of the radius of the furnace bottom;

referring to fig. 13 and 17, an installation groove 60 of the furnace body 2 is formed in the base 7, the furnace bottom 5 is installed on the installation groove 60, and the installation groove 60 and the furnace bottom 5 are insulated by an insulating mica sheet 61; the furnace body 2 is arranged on the furnace bottom 5, the upper end of the frame type stirrer 9 is arranged in the stirrer mounting opening 24 at the center of the furnace cover 10, and the upper end of the freeze-thaw valve 62 is aligned with the material leaking hole 50 and is arranged below the base 7; covering the furnace cover 10 on the furnace body 2 through the furnace cover buckle 20 and the mounting buckle 11 of the upper circular ring water outlet distribution ring 12, so that the stainless steel metal ball 74 is above the material leakage hole 50 of the furnace bottom 5, and the symmetry axis of the frame type stirrer 9, the spherical center of the stainless steel metal ball 74, the center of the material leakage hole 50 and the symmetry axis of the freeze-thaw valve 62 are on the same straight line;

referring to fig. 14 and 15, there are two ways of mounting the freeze/thaw valves 62 on the furnace floor 5: bolt-on freeze-thaw valve lug mounting and screw-on mounting, two mounting embodiments of the freeze-thaw valve 62 are described below:

referring to fig. 14A, 14B and 14C, in the mounting example 1, the freeze/thaw valve mounting port 51 of the furnace bottom 5 is tapered in external shape and welded to the furnace bottom 5. 3L-shaped stainless steel blocks 68 are welded on the furnace bottom 5, threaded holes are formed in the L-shaped stainless steel blocks 68, tightening bolts 69 are installed in the threaded holes, the freeze-thaw valve 62 is made of platinum, a conical connector 64 is arranged at the upper end of the freeze-thaw valve, and the conical degree of the freeze-thaw valve is the same as that of the conical connector 51 of the furnace bottom. 3 mounting lugs 63 are welded at the tapered interface 64. The lower end of the freeze-thaw valve is a cylinder 67 with an inner diameter of 16mm, the upper end of the cylinder 67 is welded with a water-cooling or air-cooling spiral pipe 65 with a rectangular cross section, the lower end of the cylinder 67 is an intermediate frequency induction coil 66, when the freeze-thaw valve is installed, the freeze-thaw valve lug 63 is positioned between two L-shaped stainless steel blocks 68 and clings to the bottom of the furnace, and then rotates anticlockwise, the lug 63 is placed above the L-shaped stainless steel block 68, and then 3 puller bolts 69 are screwed down to enable the inner conical surface of the freeze-thaw valve conical interface 64 and the outer conical surface of the furnace bottom conical interface 51 to be tightly attached, so that glass is prevented from entering a gap between the freeze-thaw valve and the furnace.

Referring to the installation example 2 of fig. 15A, 15B and 15C, a circular threaded hole 70 is welded around the center of the furnace bottom 5. Fig. 15B is a structural view of a freeze/thaw valve 62 of installation example 2. The freeze/thaw valve 62 is made of nickel-chromium-iron alloy, and has a threaded interface 64 at its upper end and a threaded outer side that mates with the threaded hole 70 in the furnace bottom 5. The inner side of the threaded interface 64 is a cone which is matched with the conical interface 51 of the furnace bottom 5. The lower end of the freeze-thaw valve 62 is a cylinder 71, the upper end of the freeze-thaw valve is welded with a water-cooling or air-cooling spiral pipe 65 with a rectangular cross section, the lower end of the freeze-thaw valve is provided with a medium frequency induction coil 66, and the middle of the freeze-thaw valve is welded with an octagonal nut 72. When the freeze-thaw valve 62 is installed, the freeze-thaw valve is placed in the furnace bottom threaded hole 70 and is screwed down through the octagonal nut 72, so that the inner conical surface of the freeze-thaw valve threaded interface 64 is tightly attached to the outer conical surface of the furnace bottom conical interface 51, and glass is prevented from entering a gap between the freeze-thaw valve threaded interface 64 and the furnace bottom conical interface 51.

Referring to fig. 16, the frame stirrer 9 is a stainless steel water-cooling stirrer and is composed of a stirring rod 77, a stirring frame 73 and a stainless steel metal ball 74 at the lower end, and the cooling water inside the frame stirrer 9 flows from top to bottom through a water inlet pipe 75 at both sides of the stirring rod and turns back through the stirring frame 73 at both sides and flows upwards through a central pipe 76 of the stirring rod to discharge water.

The process of use of the glass melting furnace of the invention is described below:

starting glass with the components similar to those of the target product is added through a furnace cover feeding port 23, and after part of the starting glass enters the material leaking hole 50 and the freeze-thaw valve 62, the frame type stirrer 9 is descended to block the material leaking hole 50. The addition of the start-up glass was then continued to the start-up position of the furnace, and a metallic zirconium ring was placed on the start-up glass. The method comprises the steps of starting cooling water of a glass melting furnace, cooling water of a frame type stirrer, cooling gas of a freeze-thaw valve and gas of a bubbler, switching on a high-frequency power supply, heating a metal zirconium ring by an induction coil 3, transferring heat to starting glass by the metal zirconium ring to melt the starting glass, and starting to add product glass raw materials (powder raw materials, glass beads, slurry or waste liquid) through a feed inlet 23 after the starting glass is completely melted. As the furnace body and the furnace bottom are water-cooled, glass solidified shells with the thickness of 5-10mm and 15-30mm are respectively formed on the furnace wall and the furnace bottom, so that the furnace wall and the furnace bottom are not directly contacted with molten glass, the furnace wall and the furnace body are protected, the service life of the glass melting furnace is prolonged, the original components of the glass are not influenced, and the glass performance is improved. The liquid level is measured through the liquid level measuring port 17, the temperature is measured through the temperature measuring port 22, and the inside of the furnace is monitored through the window 18.

When the glass melting process parameter reaches the target value, the frame stirrer 9 is lifted to the stirring position and the rotation is started. When the glass liquid level reaches the material leakage liquid level, the cooling 65 of the spiral pipe of the freeze-thaw valve 62 is stopped, the medium-frequency induction heating coil 66 is started, and the glass starts to leak. When the liquid level of the leaked glass is up to the stop level, the spiral tube cooling 65 is started, the stirrer 9 is stopped and lowered, so that the metal balls 74 of the stirrer 9 block the leaking hole 50 at the bottom of the furnace, the power of the medium-frequency induction heating coil 66 is gradually reduced, the glass at the freeze-thaw valve port is drained, and simultaneously the glass is solidified at the spiral cooling tube 65 of the freeze-thaw valve, and the leaked glass stops. After the glass leakage stops, the stirrer 9 is lifted up and the next glass melting cycle is started.

Claims

1. A glass melting furnace comprises a furnace body (2) and a refractory concrete base (7) with supporting legs (8), wherein the furnace body (2) is fixed on the base (7) through a screw rod (4), the top of the furnace body (2) is provided with a furnace cover (10), and the bottom of the furnace body is provided with a furnace bottom (5), the glass melting furnace is characterized in that the furnace cover (10) is of a cavity structure, a cooling channel (25) with a rectangular cross section is welded in the cavity, the furnace cover (10) is provided with an air inlet (16) and an air outlet (19) which are respectively communicated with the cooling channel (25), and the center of the furnace cover (10) is provided with a stirrer mounting hole (24) for a stirrer (9) to extend into the furnace body (2); a liquid level measuring port (17), a window (18), a tail gas discharge port (21), a temperature measuring port (22) and a feeding port (23) are also arranged on the furnace cover (10);

the furnace body (2) is a cylinder formed by a plurality of stainless steel sleeves (14) in a surrounding mode, the top surface and the bottom surface of the furnace body are formed by welding an upper circular ring water outlet distribution ring (12) and a lower circular ring water inlet distribution ring (13), each stainless steel sleeve (14) consists of an inner pipe (43), an outer pipe (42) sleeved outside the inner pipe (43) and a cover plate (47) covering the bottom of the outer pipe (42), the inner pipe (43) and the outer pipe (42) are connected through a support (44), a water outlet (45) is formed in the upper end of the inner pipe (43), and a water inlet (46) is formed in the upper end of the outer pipe (42);

the furnace bottom (5) is in a split-valve radial shape (48), the central angle corresponding to each valve (48) is 30-45 degrees, the length of a split-valve slit (52) is 1/2-2/3 of the radius of the furnace bottom, the gap between the valves is filled with aluminate refractory cement, a bubbler (49) is arranged on each split valve (48), a water cooling tank (57) is welded below each split valve (48), the inside of the water cooling tank (57) is divided into an outer water inlet tank (58) and an inner water outlet tank (59) by a metal plate (55), the volume of the water inlet tank (58) is smaller than that of the water outlet tank (59), and the water inlet tank (58) and the water outlet tank (59) are respectively provided with a water inlet pipe (53) and a water outlet pipe (54); a material leakage hole (50) is formed in the center of the furnace bottom (5), and a mounting interface (51) of a conical freeze-thaw valve (62) is welded on the furnace bottom and is used for connecting the freeze-thaw valve (62);

the cooling water in the frame type stirrer (9) flows from top to bottom through water inlet pipelines (75) at two sides of the stirring rod, and the stirring frames (73) at two sides are folded and then go out through a central pipeline (76) of the stirring rod;

an installation groove (60) of the furnace body (2) is formed in the base (7), the furnace bottom (5) is installed on the installation groove (60), and the installation groove (60) and the furnace bottom (5) are insulated through an insulating mica sheet (61); the furnace body (2) is arranged on the furnace bottom (5), the upper end of the frame type stirrer (9) is arranged in a stirrer mounting opening (24) in the center of the furnace cover (10), and the upper end of the freeze-thaw valve (62) is aligned with the material leaking hole (50) and arranged below the base (7); the furnace cover (10) is covered on the furnace body (2) through the furnace cover buckle (20) and the mounting buckle (11) of the upper circular ring water outlet distribution ring (12), so that the stainless steel metal ball (74) is arranged above the material leakage hole (50) of the furnace bottom (5), and the symmetry axis of the frame type stirrer (9), the sphere center of the stainless steel metal ball (74), the center of the material leakage hole (50) and the symmetry axis of the freeze-thaw valve (62) are on the same straight line.

2. The glass melting furnace according to claim 1, wherein the upper ring water outlet distribution ring (12) and the lower ring water inlet distribution ring (13) are divided into N partitions by a partition plate, the value range of N is 8-16, N stainless steel sleeves (14) are communicated in each partition, the value range of N is 6-8, and gaps between adjacent stainless steel sleeves (14) are filled with mica sheets for insulation; the distance between the upper circular ring water outlet distribution ring (12) and the lower circular ring water inlet distribution ring (13) is 1-3cm, and the effective volume in the cavity of the upper circular ring water outlet distribution ring (12) is larger than the effective volume in the cavity of the lower circular ring water inlet distribution ring (13).

3. The glass melting furnace according to claim 1 or 2, wherein the upper ring water outlet distribution ring (12) is formed by welding a top cover (29), an outer side plate (30), a bottom plate (31) and an inner side plate (32), the upper ring water outlet distribution ring is divided into N partitions by a partition plate (33), a water outlet pipe (26) and a pressure relief valve (27) are arranged on the outer side plate (30) of each partition, a stainless steel sleeve (14) inner pipe (43) welding opening (28) is arranged on the bottom plate (31), and two mounting buckles (11) are arranged on the outer side plate of the upper ring water outlet distribution ring (12);

lower ring intake water distribution ring (13) form by roof (40), outer panel (39), bottom plate (38) and interior plate (37) welding, divide into N by baffle (41) and cut off, weld on outer panel (39) of every partition has a inlet tube (36) bottom plate (38) on have stainless steel sleeve (14) outer tube (42) welding opening (35) roof (40) on have stainless steel sleeve (14) inner tube (43) welding opening (34), the cooling water flow in stainless steel sleeve (14) is to being: enters the outer pipe (42) through the water inlet (46), turns downwards along the outer pipe (42), turns over the cover plate (47) and upwards along the inner pipe (43), and flows out of the water outlet (45).

4. The glass melting furnace according to claim 1, wherein the freeze-thaw valve (62) is made of NiCrFe alloy or platinum, the freeze-thaw valve (62) is water-cooled or air-cooled by a rectangular cross-section spiral pipe (65) and is heated by an induction coil (66), an inner conical surface of an upper end interface (64) of the freeze-thaw valve (62) is matched with a furnace bottom conical interface (51), and the freeze-thaw valve (62) is installed in a bolt tightening lug installation mode or a thread tightening installation mode:

when the freeze-thaw valve (62) is in a threaded fastening installation mode, the threaded interface (64) at the upper end of the freeze-thaw valve (62) is screwed into the furnace bottom threaded hole (70) and is screwed down through the octagonal nut (72), so that the inner conical surface of the freeze-thaw valve threaded interface (64) is tightly attached to the outer conical surface of the furnace bottom conical interface (51);

when freeze-thaw valve (62) for bolt puller lug mounting means, freeze-thaw valve (62) upper end toper interface (64) department welding have 3 installation lugs (63), stove bottom (5) on the welding have 3L type stainless steel pieces (68), L type stainless steel piece (68) are opened threaded hole, threaded hole has installation puller bolt (69).

5. The glass melting furnace according to claim 1, wherein the furnace cover (10), the furnace body (2), the furnace bottom (5) and the frame stirrer (9) are made of stainless steel 304 or 316, and a buckle (20) mounted with the furnace body (2) is arranged on the outer side wall of the furnace cover (10).

6. The glass melting furnace according to claim 1, wherein said frame stirrer (9) is a stainless steel water-cooled stirrer consisting of a stirring rod (77), a stirring frame (73) and a stainless steel metal ball (74) at the lower end.

7. A glass melting furnace according to claim 6, characterized in that the stainless steel metal balls (74) provided at the lower end of the frame stirrer (9) have a diameter of 30 to 50 mm.

8. The glass melting furnace according to claim 1 or 2, wherein the inner tube (43) of the stainless steel sleeve (14) has a diameter of 8 to 18mm and a wall thickness of 1 to 2mm, and the outer tube (42) has a diameter of 16 to 30mm and a wall thickness of 2 to 5 mm.

9. The glass melting furnace according to claim 1 or 2, wherein a gap between adjacent split stainless steel sleeves (14) of the furnace body (2) is 1-2 mm, and mica sheets are filled in the gap for insulation.

10. A glass melting furnace according to claim 1, characterized in that said bubblers (49) are located on a circumference centered on the center of the hearth 5.

11. A glass melting furnace according to claim 1, characterised in that the distance of the water cooling box (57) from the centre of the hearth is 1/3-1/2 of the radius of the hearth.

12. The glass melting furnace according to claim 1, wherein the thickness of the hearth (5) is 3 to 4cm, the diameter of the upper end of the central funnel (50) is 20 to 30mm, and the diameter is reduced downward at an angle of 10 to 15 °, and an interface (51) is welded to the hearth and mounted on a conical freeze-thaw valve (62), and the interface is also reduced downward at an angle of 10 to 15 °.

13. A glass melting furnace according to claim 1, characterised in that the hearth (5) is embedded in a refractory cement concrete foundation (7), the refractory cement concrete foundation (7) being made of aluminate cement concrete, steel reinforcement and fibreglass.

14. The glass melting furnace according to any of the claims 1 to 13, characterized in that the insulating mica sheets (61) between the installation groove (60) and the furnace bottom (5) have a thickness of 3 to 5 mm.