CN103882516B - The online feed supplement method of polycrystalline silicon ingot or purifying furnace - Google Patents

Abstract

The invention discloses an online feeding method for a polycrystalline silicon ingot furnace, which solves the problems of low utilization rate of crucible consumables and greatly reduced production output in the existing polycrystalline silicon production process. Including when the bulk polysilicon material set in the quartz crucible (23) is in a semi-molten state, and when the filling height H (25) vacated in the quartz crucible (23) is greater than 100 mm, open the gate valve (8), Slide the hopper (12) to the right, so that the discharge end of the screw feeder (10) enters the left material inlet (7) of the guide bin (5), and start the screw feeder drive motor (13) For feeding, the polysilicon granules in the hopper (12) pass through the guide bin (5) and the feeding pipe (4), and pass through two semicircular buffer blocks arranged at intervals at the outlet of the feeding pipe (4) The feed sheet (22) enters the quartz crucible (23). It has realized the reduction of energy consumption per unit of production and the increase of the production capacity of a single device.

Description

On-line Replenishment Method for Polysilicon Ingot Furnace

technical field

The invention relates to a feeding method for a polycrystalline silicon ingot furnace, in particular to a method for online feeding during the production process of a polycrystalline silicon ingot furnace.

Background technique

Silicon-based solar energy has unique advantages in alleviating energy shortage and protecting the environment. The key to its development is that the production process of polysilicon as the base material of solar cells is very expensive, especially in the growth process of polysilicon ingots, various losses account for a large proportion. How to reduce the loss cost of this production link has become the main problem that various manufacturers at home and abroad are eager to solve. At present, the growth of polysilicon ingots is mainly to put the silicon material into the square high-purity quartz crucible, and all the silicon materials are put into the crucible for the first time. Due to the irregular shape of the silicon material, the crucible will There will be many gaps. In the subsequent heating process, after the bulk silicon material in the crucible is melted, a certain empty space will be formed on the upper part of the crucible. Since the crucible is a disposable consumable in the production process, its space cannot be fully utilized, which brings the defect of low utilization rate of consumables and greatly reduces the production output.

Contents of the invention

The invention provides an online feeding method for a polysilicon ingot furnace, which solves the technical problems of low utilization rate of crucible consumables and greatly reduced production output in the existing polysilicon production process.

The present invention solves the above technical problems through the following technical solutions:

A method for online feeding of polysilicon ingot furnace, comprising the following steps:

The first step is to set the feeding port on the roof of the polysilicon ingot casting furnace, set the feeding bin on the feeding port, and set the feeding pipe of the feeding bin on the quartz in the polysilicon ingot furnace body through the feeding port. Above the crucible, the left support plate of the guide rail and the right support plate of the guide rail are respectively set on the top cover of the polysilicon ingot casting furnace, and the sliding guide rail is set between the left support plate of the guide rail and the right support plate of the guide rail. On the guide rail, a screw feeder is set at the bottom of the hopper, polysilicon granules are set in the hopper, and a retractable material guide bellows is set between the hopper outlet and the left material inlet of the guide bin, and the screw feeds The discharge end of the machine is set in the material guide bellows, and a vacuum pump is set on the roof of the polysilicon ingot furnace, and the vacuum port of the vacuum pump is connected with the air suction port set on the hopper through a retractable vacuum bellows;

The second step is to close the flapper valve set on the left side of the material inlet of the guide bin, and start the vacuum pump to vacuum the hopper to the state required by the process;

The third step, determine the theoretical feeding time t: first determine the mass M _block of the bulk polysilicon material in the quartz crucible, measure the temperature T _of the bulk polysilicon material in the quartz crucible after melting, according to the block polysilicon The _melting point temperature Tmelt of the material and the specific heat of the polysilicon liquid state C _liquid , using the following formula: Q _half = C _liquid (T _liquid - T _melt ) M _block / 2, can calculate the bulk polysilicon material contained in the quartz crucible is half The theoretical heat Q _half released in the molten state; then according to the temperature T of the polysilicon _granules set in the hopper and its specific heat C, the theoretical heat Q _half is absorbed by the polysilicon _granules and the amount M that is completely melted can be calculated The calculation formula is: M _pieces = _Q½ /[C _pieces ( _{Tmelt -} T _pieces ), since the power output of the heater will increase correspondingly during the feeding process, so M _pieces at this time are absolutely safe to add weight, Finally, according to the feeding speed V of the screw feeder, the theoretical feeding time t=M _grains /V can be calculated;

Step 4: When the massive polysilicon material set in the quartz crucible is in a semi-molten state, and the refillable height H vacated in the quartz crucible is greater than 100 mm, open the gate valve, slide the hopper to the right, and make the screw feed The discharge end of the feeder enters the left material inlet of the material guide bin, and the screw feeder is started to drive the motor to replenish the material. The polysilicon particles in the hopper pass through the material guide bin and the discharge pipe, and pass through the discharge pipe. Two semi-circular buffer baffle plates arranged at intervals at the outlet of the outlet enter the quartz crucible;

Step 5. When the feeding time reaches the theoretical feeding time calculated in the third step, turn off the drive motor of the screw feeder and slide the hopper to the left so that the discharge end of the screw feeder leaves the left side of the guide bin. At the side inlet, close the gate valve, and the online feeding ends.

An online feeding system for a polysilicon ingot casting furnace, comprising a polysilicon ingot casting furnace body, a feeding port is provided on the top cover of the polysilicon ingot casting furnace, and guide rail left support plates are respectively arranged on the top cover of the polysilicon ingot casting furnace And the right support plate of the guide rail, a sliding guide rail is set between the left support plate of the guide rail and the right support plate of the guide rail. The hopper is set on the sliding guide rail through the sliding base of the hopper. For polysilicon granules, a guide bin is fixed on the right side of the right support plate of the guide rail. The feeding pipe of the guide bin is set above the quartz crucible in the furnace body of the polysilicon ingot casting furnace through the feeding port. There is a slide valve on the left side of the material inlet of the silo, a retractable material guide bellows is set between the hopper outlet and the left side of the material guide silo, and the discharge end of the screw feeder is set In the material guide bellows, the screw feeder drive motor is connected to the left end of the screw feeder, the screw feeder drive motor is set on the support base, and the support base is fixed on the sliding base of the hopper. A vacuum pump is arranged on the top cover of the ingot furnace, and the vacuum port of the vacuum pump communicates with the air pump port provided on the hopper through a retractable vacuum bellows.

There are at least two semicircular buffer baffles at intervals at the outlet of the feeding tube, a material guide observation window is provided on the top of the material guide bin, and an openable vacuum sealing cover is provided on the top of the hopper; in the quartz crucible A semi-molten bulk polysilicon material is arranged in the crucible, and the filling height H vacated in the quartz crucible is greater than 100 mm.

The invention has simple structure and convenient operation, can determine reasonable feed speed and feed weight through calculation, and realizes the reduction of energy consumption per unit product and the increase of production capacity of a single device.

Description of drawings

Fig. 1 is a schematic structural view of the present invention.

detailed description

The present invention is described in detail below in conjunction with accompanying drawing:

A method for online feeding of polysilicon ingot furnace, comprising the following steps:

The first step is to set the feeding port 3 on the roof 2 of the polysilicon ingot casting furnace, set the feeding bin 5 on the feeding port 3, and set the feeding pipe 4 of the feeding bin 5 on the polysilicon through the feeding port 3 Above the quartz crucible 23 in the ingot furnace body 1, the left support plate 15 of the guide rail and the right support plate 16 of the guide rail are respectively arranged on the roof 2 of the polycrystalline silicon ingot furnace, and the left support plate 15 of the guide rail and the right support plate 16 of the guide rail A sliding guide rail 17 is arranged between them, and the hopper 12 is movably arranged on the sliding guide rail 17 through the hopper sliding base 18. A screw feeder 10 is arranged at the bottom of the hopper 12, and polysilicon granules are placed in the hopper 12. Between the hopper outlet 11 and A retractable material guide bellows 9 is set between the left side material inlet 7 of the material guide bin 5, and the discharge end of the screw feeder 10 is arranged in the material guide bellows 9, and the polysilicon ingot furnace roof 2 A vacuum pump 19 is arranged on the top, and the vacuum port of the vacuum pump 19 communicates with the air port 21 provided on the hopper 12 through a retractable vacuum bellows 20;

The second step is to close the flapper valve 8 provided on the left side material inlet 7 of the material guide bin 5, and start the vacuum pump 19 to evacuate the hopper 12 to the state required by the process;

The 3rd step, determine the theoretical feeding time t: first determine the mass M _block of the block polysilicon material that is installed in the quartz crucible 23, measure the temperature T _liquid after the block polysilicon material that is installed in the quartz crucible 23 melts, according to block Polysilicon material melting point temperature T _melting and polysilicon liquid specific heat C _liquid , utilize following formula: Q _half =C _liquid (T _liquid -T _melting ) M _piece /2, can calculate the adorned block polysilicon material in the quartz crucible 23 The theoretical heat Q _half released when in a semi-molten state; then according to the temperature T of the polysilicon _pellets set in the hopper ₁₂ and its specific heat C, it can be calculated that the theoretical heat Q _half is completely melted after being absorbed by the polysilicon pellets The amount of M _pieces , the calculation formula is: M _pieces = Q _half / [C _pieces (T _melting - T _pieces ), and finally according to the feeding speed V of the screw feeder 10, the theoretical feeding time t = M _pieces can be calculated /V;

Step 4: When the bulk polysilicon material set in the quartz crucible 23 is in a semi-molten state, and the refillable height H25 vacated in the quartz crucible 23 is greater than 100 mm, open the slide valve 8 and slide the hopper 12 to the right , so that the discharge end of the screw feeder 10 enters the left side material inlet 7 of the guide bin 5, starts the drive motor 13 of the screw feeder to replenish the material, and the polysilicon particles in the hopper 12 pass through the guide bin 5 and the blanking tube 4, and enter in the quartz crucible 23 through two semicircular buffer baffle plates 22 arranged at intervals at the outlet of the blanking tube 4;

The fifth step, when the feeding time reaches the theoretical feeding time calculated in the third step, turn off the driving motor 13 of the screw feeder, slide the hopper 12 to the left, and make the discharge end of the screw feeder 10 leave the material guide The left side material inlet 7 of the bin 5 closes the gate valve 8, and the online feeding ends.

An online feeding system for a polysilicon ingot casting furnace, comprising a polysilicon ingot casting furnace body 1, a feeding port 3 is arranged on the roof 2 of the polysilicon ingot casting furnace, and a feeding port 3 is respectively arranged on the roof 2 of the polysilicon ingot casting furnace Guide rail left support plate 15 and guide rail right support plate 16, between guide rail left support plate 15 and guide rail right support plate 16, be provided with slide guide rail 17, hopper 12 is arranged on slide guide rail 17 by hopper sliding base 18 activities, in hopper 12 A screw feeder 10 is arranged at the bottom of the bottom, polysilicon granular material is arranged in the hopper 12, and a guide bin 5 is fixedly arranged on the right side of the right support plate 16 of the guide rail, and the feeding pipe 4 of the guide bin 5 passes through the supplementary The feed port 3 is arranged above the quartz crucible 23 in the polysilicon ingot casting furnace body 1, and a slide valve 8 is arranged on the left side feed port 7 of the material guide bin 5, and between the hopper outlet 11 and the feed bin A retractable material guide bellows 9 is arranged between the left side material inlet 7 of 5, the discharge end of the screw feeder 10 is set in the material guide bellows 9, and the left end of the screw feeder 10 is connected with a screw The feeder drive motor 13, the screw feeder drive motor 13 is arranged on the support base 14, the support base 14 is fixedly arranged on the hopper sliding base 18, and a vacuum pump 19 is arranged on the roof 2 of the polysilicon ingot furnace. The vacuum port of the vacuum pump 19 communicates with the air port 21 provided on the hopper 12 through a retractable vacuum bellows 20 .

At least two semicircular buffer baffles 22 are arranged at intervals at the outlet of the feeding pipe 4, a material guide observation window 6 is provided on the top of the material guide bin 5, and an openable vacuum seal is provided on the top of the hopper 12. Cover 26; semi-molten bulk polysilicon material is arranged in the quartz crucible 23, and the filling height H25 vacated in the quartz crucible 23 is greater than 100 mm.

The process of polysilicon ingot casting is divided into five stages: heating, melting, crystal growth, annealing, and cooling. Each stage has different process status and technical parameters. In the eighth step of the M8 melting stage, the silicon material starts to melt from the top and flows to the bottom of the crucible, and the upper space of the crucible is continuously reserved. Later, with the continuous melting of the silicon material, more space is left on the upper part of the crucible. At this time, the hopper 12 is moved out to the left along the sliding guide rail 17, the flapper valve 8 is closed, the hopper cover of the hopper 12 is opened, and granular material is added in, after adding, close the hopper cover, turn on the vacuum pump 19, and evacuate the hopper 12 After the vacuum reaches the target, open the slide valve 8, push the hopper 12 to the right to the feeding position, and turn on the screw feeder 10 to feed the furnace. At this time, the small-diameter pellets can be slowly fed through the feeding mechanism Heating the crucible, observe the melting of the silicon material in the crucible through the observation hole on the top. After the hopper is replenished with granular material, it can be operated repeatedly for multiple replenishment. If the increase in the amount of each furnace is calculated on the basis of 150 kg on average, the energy consumption per unit of silicon ingot will be reduced by 14% from the original 8 kWh/kg to 6.9 kWh/kg, and the production capacity of each equipment will be increased by 20%. , The non-silicon cost of the comprehensive unit silicon ingot has been reduced by 18%, and the effect is very obvious.

Claims (1)

1. the online feed supplement method of polycrystalline silicon ingot or purifying furnace, comprises the following steps:

The first step, material-feeding port (3) is set on polycrystalline silicon ingot or purifying furnace furnace top cover (2), guide storehouse (5) is set on material-feeding port (3), the tremie pipe of guide storehouse (5) (4) is arranged on to the top of the silica crucible (23) in polycrystalline silicon ingot casting furnace body (1) by material-feeding port (3), guide rail left support plate (15) and guide rail right support plate (16) are set respectively on polycrystalline silicon ingot or purifying furnace furnace top cover (2), between guide rail left support plate (15) and guide rail right support plate (16), rail plate (17) is set, hopper (12) is movably arranged on rail plate (17) by hopper sliding bottom (18), in the bottom of hopper (12), screw(-type) feeder (10) is set, in hopper (12), place polycrysalline silcon material, between hopper discharging opening (11) and the left side feeding mouth (7) of guide storehouse (5), telescopic guide bellows (9) is set, the discharge end of screw(-type) feeder (10) is arranged in guide bellows (9), vavuum pump (19) is set on polycrystalline silicon ingot or purifying furnace furnace top cover (2), the vacuum orifice of vavuum pump (19) is connected together with the upper bleeding point (21) arranging of hopper (12) by the telescopic bellows (20) that vacuumizes,

Second step, the push-pull valve (8) that the left side feeding mouth (7) of guide storehouse (5) is above arranged are closed, and start vavuum pump (19) hopper (12) is evacuated down to technological requirement state;

The 3rd step, determine theoretical feed supplement time t: the mass M of first determining the chunk polysilicon material filling in silica crucible (23)_Piece, measure the temperature T after the chunk polysilicon material filling in silica crucible (23) melts_Liquid, according to the melting temperature T of chunk polysilicon material_MoltenWith polysilicon liquid specific heat C_Liquid, utilize following formula:

Q_Half=C_Liquid（T_Liquid-T_Molten）M_Piece/ 2, can calculate the theoretical heat Q that the chunk polysilicon material filling in silica crucible (23) discharges in the time of semi-molten state_Half; Again according to the temperature T of the polycrysalline silcon material arranging in hopper (12)_?With its specific heat C_?, can calculate theoretical heat Q_HalfThe amount M all melting after being absorbed by polycrysalline silcon material_?, computing formula is: M_?=Q_Half/[C_?（T_Molten-T_?), finally can calculate theoretical feed supplement time t=M according to the delivery rate V of screw(-type) feeder (10)_?/V；

The 4th step, the chunk polysilicon material arranging in the silica crucible (23) is during in semi-molten shape, and in silica crucible (23), vacate can feed supplement height H (25) be greater than 100 millimeters time, open push-pull valve (8), hopper (12) is slided to the right, make the discharge end of screw(-type) feeder (10) enter into the left side feeding mouth (7) in guide storehouse (5), start screw(-type) feeder drive motors (13) and carry out feed supplement, polycrysalline silcon material in hopper (12) is by guide storehouse (5) and tremie pipe (4), and the two semicircle bumper flitch (22) that arrange through the outlet compartment of terrain at tremie pipe (4) enter into silica crucible (23),

The 5th step, in the time that the feed supplement time reaches the theoretical feed supplement time that the 3rd step calculates, close screw(-type) feeder drive motors (13), hopper (12) is slided left, make the discharge end of screw(-type) feeder (10) leave the left side feeding mouth (7) in guide storehouse (5), close push-pull valve (8), online feed supplement finishes.