High-energy baking device for aluminum electrolytic cell, high-energy baking electrolytic cell mechanism, and starting method

Abstract

The application provides a high-energy baking device for an aluminum electrolytic cell, a high-energy baking electrolytic cell mechanism and a starting method. The device comprises a main station, a gas station, a gas supply mechanism, a combustion rack and a plurality of burners. The plurality of burners are arranged in two rows in pairs and are respectively arranged at the inner sides of the two long sides of the electrolytic cell. The nozzles of the two rows of burners are arranged oppositely or crossly. The combustion rack is arranged corresponding to the two rows of burners and is used for installing the pipelines for supplying gas and air. The gas station is communicated with the gas pipeline on the combustion rack through the pipeline. The air pipeline on the combustion rack is communicated with the gas supply mechanism. The main station is connected with the gas station, the combustion rack, the gas supply mechanism and the burners to control the working states of the gas station, the combustion rack and the burners. By arranging reasonable burner assemblies in the electrolytic cell and configuring corresponding refractory structures, the baking temperature can reach the degree of molten electrolyte, and then the additional electrolysis is no longer needed, and the step of filling the electrolyte is cancelled. The device can save energy and increase efficiency, and can protect the electrolytic cell.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electrolytic cell roasting and starting, in particular to a high-energy roasting device for aluminum electrolytic cells, a high-temperature roasting electrolytic cell mechanism and a starting method. BACKGROUND

[0002] Aluminum electrolytic cell gas roasting technology is a new roasting method that has emerged in the past decade and is increasingly widely used. The main operation process of the prior art is as follows:

[0003] Through the gas roasting device, the temperature of the cathode surface of the electrolytic cell is heated to 700-950°C (CN 201883155U or CN 110042427B) according to the predetermined temperature curve, and the final roasting temperature varies slightly due to the size of the cell type;

[0004] Stop the fire and remove the roasting device;

[0005] Pour in the electrolyte;

[0006] Perform the power-on and cell starting operation.

[0007] The above process requires short operation intervals and tight connections. The entire operation time is generally controlled within 30 minutes. Once the operation time is too long, it will cause the starting voltage to be too high, the starting risk to be large, and even the starting to fail.

[0008] The main problems of the roasting device in the prior art are:

[0009] The highest roasting temperature can only reach 950°C, which does not reach the temperature of electrolyte melting. If the set time is exceeded, the electrolyte will be cooled down;

[0010] The combustion load is small, and the heating intensity per unit area is insufficient, only 41.5KW, which cannot meet the heating intensity required for melting the electrolyte;

[0011] The heat preservation cover plate used is made of stainless steel material. When the temperature is further increased, the current heat preservation cover plate deforms severely and cannot meet the use requirements;

[0012] For aluminum electrolytic production, it is more troublesome to cultivate liquid electrolyte. Generally, 3-8 in-production electrolytic cells are needed to cultivate electrolyte when starting one electrolytic cell. The cultivation of electrolyte in the in-production electrolytic cell will damage the normal production process conditions, the furnace will be melted, and it will also take some time to restore the normal production process conditions.

[0013] For the aluminum electrolysis production, the electrolyte extraction is more cumbersome, the first is easy to extract aluminum water, the second is easy to block the bag pipe, these two problems can cause the failure of starting groove, when the aluminum water is extracted more, pouring into the baking starting groove will cause the voltage swing in the process of starting to be serious, even the rolling aluminum phenomenon, when the rolling aluminum is serious, the groove will have to be stopped; when the bag pipe is blocked and not handled in time, the temperature of the baking groove will decrease obviously, which does not have the condition of power transmission, thereby causing the failure of starting groove.

[0014] Therefore, for the current aluminum electrolysis cell baking technology, it is urgent to design a design that can solve a series of technical problems brought by filling molten electrolyte to avoid the above problems.

[0015] In order to solve the above problems, people have been seeking an ideal technical solution. SUMMARY

[0016] The purpose of the present application is to overcome the shortcomings of the prior art, and to provide an aluminum electrolysis cell high-energy baking device, a high-temperature baking electrolysis cell mechanism and a starting method, which can directly melt the electrolyte at a high temperature, no longer need external culture and electrolyte extraction, reduce the baking steps, and make the electrolysis cell start more safely, quickly and stably.

[0017] The basic design concept of the present application is that in the baking process of the electrolysis cell, the traditional baking structure is modified, the refractory fiber module as a sealing material is laid on the A / B surface of the electrolysis cell, and then the burners are installed in groups on the A / B surface of the electrolysis cell for high-temperature baking of the electrolysis cell. The final baking temperature reaches 950°C-1100°C, which can melt the electrolyte. In this case, whether it is traditional electrolyte filling or direct melting of solid electrolyte in the electrolysis cell, the state of the electrolyte can be kept stable, and the step of filling electrolyte can be omitted in the direct melting mode, solving a series of problems brought by filling electrolyte.

[0018] In order to achieve the above purpose, the technical scheme adopted by the present application is: an aluminum electrolysis cell high-energy baking device, comprising a main station, a gas station, a wind supply mechanism, a combustion rack and a plurality of burners;

[0019] The plurality of burners are arranged in two rows in pairs and are respectively used for being installed at the inner sides of the two long sides of the electrolysis cell. The nozzles of the two rows of burners are oppositely arranged or cross arranged to make the high-temperature gas flow gather and form a baking temperature of 950°C-1100°C.

[0020] The combustion rack is provided corresponding to the two rows of burners and is used for installing the pipelines for supplying gas and air. A plurality of gas branch pipes and air branch pipes for connecting the burners are provided on the combustion rack corresponding to each burner.

[0021] The gas station is communicated with the gas pipeline on the combustion rack through a pipeline, and the air pipeline on the combustion rack is communicated with the air supply mechanism;

[0022] The main station is connected with the gas station, the combustion rack, the air supply mechanism and the burner to control the working states of the gas station, the combustion rack and the burner.

[0023] As described above, the outer periphery of the burner is surrounded by the refractory fiber material.

[0024] As described above, the air supply mechanism is integrated in the main station.

[0025] As described above, the burner is of a split structure, comprising a combustion chamber and an upper structure, the upper structure comprising a gas inlet, an air inlet, a plug cap, a point / observation hole, a positioning plate and a fixing bolt, the gas inlet, the air inlet and the point / observation hole being mounted on the positioning plate, the plug cap being arranged at the top end of the point / observation hole, and the combustion chamber being detachably connected with the upper structure through the fixing bolt; the inner side of the combustion chamber is provided with a nozzle.

[0026] As described above, the combustion rack is of a pipeline structure arranged along the paired burners.

[0027] As described above, further comprising a temperature sensor, the temperature sensor being distributed in the heating space between the two rows of burners, and the temperature sensor being connected with the main station.

[0028] As described above, further comprising an oxygen content sensor, the oxygen content sensor being arranged in the burner, and the oxygen content sensor being connected with the main station.

[0029] A high-temperature roasting electrolytic cell mechanism, comprising an electrolytic cell and an aluminum electrolytic cell high-energy roasting device, two rows of the burners are respectively arranged on the inner sides of the two long sides of the electrolytic cell, the inner side of the electrolytic cell is provided with a refractory fiber layer, and the electrolytic cell is pre-paved with electrolyte blocks or electrolyte powder, and the refractory temperature of the refractory fiber layer is ≥1250°C.

[0030] A high-energy roasting starting method of an electrolytic cell, which is started by the following method:

[0031] Step 1) pre-pave a certain height of raw materials of electrolyte blocks or electrolyte powder in the electrolytic cell, and hang anode carbon blocks;

[0032] Step 2) install the aluminum electrolytic cell high-energy roasting device in the electrolytic cell, and the inner side wall of the electrolytic cell is provided with a refractory fiber layer with a refractory temperature ≥1250°C;

[0033] Step 3) heat preservation, and heat preservation is performed on the electrolyte or cryolite covering the upper part of the electrolytic cell;

[0034] Step 4) The main station controls the input of gas and combustion air and ignites to heat the electrolytic cell until the baking temperature reaches 950°C-1100°C;

[0035] Step 5) As the electrolyte in the electrolytic cell melts, new electrolyte blocks or raw materials of electrolyte powder are gradually filled;

[0036] Step 6) When the electrolyte is sufficient and the temperature of the anode carbon block and the cathode carbon block is also sufficient, the electrolytic cell is started.

[0037] As described above, in step 1), the pre-laid electrolyte blocks or raw materials of electrolyte powder exceed 180mm-250mm of the cathode carbon block.

[0038] The present application has the following advantages:

[0039] 1. Compared with the traditional high-temperature baking electrolytic cell scheme, the baking temperature in the electrolytic cell can be increased to the melting point of the electrolyte. Even if the traditional pouring scheme is still used, the electrolyte can still be melted after pouring, and the start-up time is more tolerant.

[0040] 2. Since the temperature in the electrolytic cell meets the melting requirement of the electrolyte, the melting process of the electrolyte can be independent of the external electrolytic cell, and the solid-state electrolyte can be laid in the electrolytic cell by heating and melting. At the same time, the cathode carbon block and the anode carbon block can be heated synchronously, saving the pouring process, shortening the operation time, and making the whole process of electrolytic cell power-on start more rapid and stable, and safer.

[0041] 3. Since the cathode carbon block is covered during the melting of the electrolyte and conducts heat through the molten electrolyte, the damage to the cathode carbon block during the baking process is completely avoided, which is beneficial to improve the service life of the electrolytic cell.

[0042] 4. The burner is designed as a split structure, and the lower combustion chamber can be replaced regularly as a consumable part, reducing the application cost.

[0043] 5. Since the electrolyte has fully penetrated the cathode and the thermal expansion cracks of the extension leg in the later baking stage, the time interval of pouring aluminum after power-on start can be significantly reduced from 24h to 4-8h, which is beneficial to improve the production efficiency and shorten the time of abnormal production management.

[0044] 6. The unit heat load of the electrolytic cell can reach 55-63KW, the final roasting temperature is at 950°C-1100°C, the air supply system is responsible for providing combustion-supporting air with Q=3000~6000Nm3 / h, P=8~30KPa to meet the 1100°C temperature rising requirement; the gas station is responsible for providing outlet gas with Q=300~600Nm3 / h, P=5~20KPa to meet the 1100°C temperature rising requirement; the roasting temperature and efficiency requirements are fully met, and the device can be used for various types of electrolytic cells with a capacity of 230KA-600KA. BRIEF DESCRIPTION OF DRAWINGS

[0045] Fig. 1 is the arrangement structure schematic diagram of the high-energy roasting device for the aluminum electrolytic cell in the application.

[0046] Fig. 2 is the frame diagram of the high-energy roasting device for the aluminum electrolytic cell in the application.

[0047] Fig. 3 is the structure schematic diagram of the burner in the application.

[0048] In the figure: 1. electrolytic cell; 2. anode carbon block; 11. main station; 12. gas station; 13. combustion frame; 14. burner; 15. refractory fiber module;

[0049] 141. gas inlet; 142. air inlet; 143. plug cap; 144. point / observation hole; 145. positioning plate; 146. fixing bolt; 147. combustion chamber; 148. nozzle;

[0050] 21. external gas inlet; 22. combustion-supporting air and gas connecting main pipe; 23. connecting pipe between the burner and the combustion frame; 24. connecting hose between the combustion frames. DETAILED DESCRIPTION

[0051] The technical solutions of the application will be further described in detail through specific embodiments.

[0052] As shown in Figs. 1-3 , a high-energy roasting device for an aluminum electrolytic cell includes a main station 11, a gas station 12, an air supply mechanism, a combustion frame 13 and a plurality of burners 14, and the attached devices have temperature sensors and oxygen content sensors, and the sealing uses refractory fiber modules 15.

[0053] If several of the burners 14 are arranged in two rows, they are arranged in pairs and are used to be installed at the inner side of the two long sides (A / B side) of the electrolytic cell 1. A refractory fiber module 15 is installed on the A / B side of the electrolytic cell 1 to form a pavement. The space around the burners 14 is also surrounded and sealed by the refractory fiber module 15. The nozzles of the two rows of burners 14 are arranged oppositely or crosswise. The distance between the adjacent burners 14 is controlled to be 500-800 mm. The installation height of the burners 14 is determined by the cooperation of the positioning plate 145 and the electrolytic cell. The design form of the burners 14 can make the high-temperature gas flow gather to form a baking temperature of 950°C-1100°C.

[0054] Specifically, the burner 14 is a split structure, which includes a combustion chamber 147 and an upper structure. The upper structure includes a gas inlet 141, an air inlet 142, a plug cap 143, a point / observation hole 144, a positioning plate 145 and a fixing bolt 146. The gas inlet 141, the air inlet 142 and the point / observation hole 144 are installed on the positioning plate 145. The plug cap 143 is arranged at the top end of the point / observation hole 144. The combustion chamber 147 is detachably connected with the upper structure through the fixing bolt 146. The inner side of the combustion chamber 147 is provided with a nozzle 148.

[0055] The combustion rack 13 is arranged corresponding to the two rows of burners 14 and is used to install the pipelines for supplying gas and air. A plurality of gas branch pipes and air branch pipes for connecting the burners 14 are arranged on the combustion rack 13 corresponding to each burner 14, which are used to supply the required air and gas for each burner 14.

[0056] The gas supply system is integrated in the main station. The gas station 12 and the main station 11 are connected with the gas pipelines and the combustion air pipelines on the combustion rack 13 through the combustion air connection main pipe 22. The temperature sensor is inserted into the middle joint position of the electrolytic cell. The oxygen content sensor is arranged in each burner.

[0057] The control system is integrated in the main station and is used to connect and control the gas station 12, the combustion rack 13, the air supply mechanism and the burners 14 to control the working state of the gas station 12, the combustion rack 13 and the burners 14. The temperature sensor is connected to control the baking temperature in the electrolytic cell.

[0058] The refractory temperature of the refractory fiber module is controlled to be ≥1250°C. The electrolyte raw material is one or more of electrolyte blocks, dielectric powder, regenerated cryolite and cryolite. The particle size range of the material is 0-35 mm. The loading amount is controlled to be higher than the height of 180-250 mm of the cathode surface and the surface is flat.

[0059] The electrolyte raw material is filled before the burners are installed so as to bury the cathode.

[0060] The control system in the main station comprises a controller, an IO module, a man-machine interface, an isolation element, a frequency converter and other conventional control elements, the air supply system mainly comprises a fan, a flow meter, a regulating valve and the like, the control system controls the whole roasting process, and the air supply system is responsible for providing combustion-supporting air with Q=3000-6000Nm3 / h and P=8-30KPa to meet the 1100°C temperature rising requirement.

[0061] The gas station is composed of a distributor, a pressure reducing valve, a quick cut-off valve, a regulating valve, a flow meter, a pressure transmitter, an anti-backfire device, a gas leakage detection device and the like, the inlet thereof is connected to the external gas inlet 21 to introduce gas, and the operation thereof is controlled by the main station; the gas station is responsible for providing outlet gas with Q=300-600Nm3 / h and P=5-20KPa to meet the 1100°C temperature rising requirement.

[0062] Through the above structure and parameter setting, the unit area heating load of the whole device is 55-63KW, and the final roasting temperature is 950-1100°C; the device can be applied to various types of electrolytic cells with a capacity of 230KA-600KA.

[0063] The high-energy roasting starting method of the electrolytic cell is as follows:

[0064] Step 1) Pre-installation preparation: a certain height of electrolyte block or dielectric powder raw material is pre-paved in the electrolytic cell 1, and exceeds the cathode by 180-250mm, then the anode carbon block 2 is hung, and the bottom palm of the anode carbon block 2 is required to be 150-300mm away from the surface of the electrolyte.

[0065] Step 2) The main station 11 and the gas station 12 are arranged on the large face of the aluminum electrolytic cell 1, the combustion rack 13 is arranged on the A / B face of the electrolytic cell 1, the burner 14 is installed on the A / B face of the electrolytic cell 1 and is put into the inside of the electrolytic cell furnace, the height of the burner put in is fixed through the positioning plate 145 of the burner 14, the distance between the burners is 500-800mm, and the periphery of the burner 14 is sealed by the refractory fiber module 15; after the main equipment is installed, the gas inlet 21 of the gas station 12 is connected to the gas main pipe, the gas station 12 and the combustion rack 13, and the main station 11 and the combustion rack 13 are respectively connected to the combustion-supporting air and the gas connection main pipe 22, the combustion racks 13 are connected through the combustion rack connection hose 24 between the combustion racks, and the combustion rack 13 and the burner 14 are connected through the burner and combustion rack connection hose 23 between the burner and the combustion rack, wherein: the gas pipe is connected to the burner 141 interface, the air pipe is connected to the burner 142 interface, the control lines of the gas station 12, the combustion rack 13 and the burner 14 are respectively connected to the main station 11, and the temperature sensor and the oxygen content sensor signal line are respectively connected to the main station 11; the temperature sensor is inserted in the middle seam position of the electrolytic cell, and the number of the temperature sensors is 3-10 according to the size of the cell type.

[0066] Step 3) Insulation, cover the upper part of the electrolytic cell with 10-15 cm thick electrolyte or ice crystals for insulation;

[0067] Step 4) Roasting: After the end of the insulation, the roasting of the electrolytic cell 1 can be started, the heating strategy setting and related control operation are carried out in the main station 11, at the same time the main station 11 provides a certain pressure and a certain amount of combustion-supporting wind according to the host control strategy, the gas station 12 provides a certain pressure and a certain amount of gas according to the host control strategy, the gas and the combustion-supporting wind are transported to the burner 14 through the combustion frame 13, mixed combustion is carried out in the combustion chamber 147 of the burner, the high-temperature flue gas after combustion enters the electrolytic cell 1 through the burner nozzle 148, and the final temperature is roasting to 950-1100°C, so that the electrolyte in the electrolytic cell furnace is melted, and the purpose of roasting is achieved. Ignition or observation during roasting is carried out through the ignition / observation hole 144 of the burner 14, Fig. 3 The burner shown is an artificial ignition / observation burner, which can be covered with a cap 143 after ignition or observation is completed.

[0068] Step 5) As the electrolyte in the electrolytic cell melts, new electrolyte blocks or raw materials of electrolyte powder are gradually filled to cover the molten electrolyte.

[0069] Step 6) When the electrolyte is sufficient and the temperature of the anode carbon block and the cathode carbon block is also sufficient, the electrolytic cell is started.

[0070] Example 1

[0071] The high-energy roasting device for the new aluminum electrolytic cell is taken as an example, and the calculation process of the heating load per unit area of the 230KA aluminum electrolytic cell equipment configuration is as follows:

[0072] (1) The 230KA aluminum electrolytic cell has an inner furnace size of 3840*11700mm; the furnace area is 3.84*11.7=44.928m2;

[0073] (2) The 230KA aluminum electrolytic cell has 32 burners, and the total power of a single burner with a power of 80KW is 80*32=2560KW;

[0074] (3) The heating load per unit area is 2560 / 44.928=56.98KW / m2;

[0075] According to the calculation result, the heating load per unit area of the high-energy roasting device for the new electrolytic cell of the 230KA cell type is 56.98KW.

[0076] Example 2

[0077] The high-energy roasting device for the new aluminum electrolytic cell is taken as an example, and the calculation process of the heating load per unit area of the 300KA aluminum electrolytic cell equipment configuration is as follows:

[0078] (1) 300KA aluminum electrolytic cell, inner hearth size: 4000*14460mm; hearth area: 4*14.46=57.84m2;

[0079] (2) 300KA aluminum electrolytic cell, the number of burners is 40, and the power of a single burner is 80KW, so the total power is: 80*40=2400KW;

[0080] (3) Unit area heating load: 3200 / 57.84=55.3KW / m2;

[0081] From the calculation results, the unit area heating load of the new high-energy baking device of 300KA cell type electrolytic cell is 55.3KW.

[0082] Example 3

[0083] The new high-energy baking device of aluminum electrolytic cell takes the configuration of 600KA aluminum electrolytic cell equipment as an example, and the unit area heating load calculation process is as follows:

[0084] (1) 600KA aluminum electrolytic cell, inner hearth size: 4270*22640mm; hearth area: 4.27*22.64=96.6728m2;

[0085] (2) 600KA aluminum electrolytic cell, the number of burners is 60, and the power of a single burner is 100KW, so the total power is: 100*60=6000KW;

[0086] (3) Unit area heating load: 6000 / 96.6728=62.06KW / m2;

[0087] From the calculation results, the unit area heating load of the new high-energy baking device of 600KA cell type electrolytic cell is 62.06KW.

[0088] From the structure characteristics of the above examples and devices, compared with the traditional baking device, the high-energy baking device has the following outstanding effects: no additional liquid electrolyte is needed during startup, the operation steps are fewer, the operation time is shorter, and the power-on startup is more safe and reliable; and during baking, the molten electrolyte has penetrated into the thermal expansion cracks that may occur during baking, which is very beneficial to improve the service life of the electrolytic cell.

[0089] It solves the pain points encountered in the use of traditional gas baking devices, uses a new high-energy gas baking device, and heats and melts a sufficient amount of liquid electrolyte while baking the electrolytic cell. Before starting, there is no need to culture electrolyte, pump electrolyte and other operations, so the operation time is shorter, and the electrolytic cell is more safe and stable during power-on start; Because the electrolyte material on the cathode surface during baking avoids the oxidation and burning of the cathode during the baking process, it is very beneficial to improve the service life of the electrolytic cell; Because the liquid electrolyte has fully penetrated the possible thermal expansion cracks of the cathode and the leg during the late baking period, the aluminum filling time interval can be significantly reduced after power-on start, from 24h to 4~8h, which is very beneficial to improve production efficiency and shorten the non-normal production management period.

[0090] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or some technical features can be replaced by equivalent ones; without departing from the spirit of the technical solutions of the present application, they should be covered in the technical solution range of the present application.

Claims

1. A method of starting up a high-energy roasting of an electrolytic cell, characterized in that: The device includes a high-energy roasting apparatus for aluminum electrolytic cells, which comprises a main station, a gas station, an air supply mechanism, a combustion rack, and several burners. The burners are arranged in pairs in two rows and are respectively installed on the inner side of the two long sides of the electrolytic cell. The nozzles of the two rows of burners are arranged opposite to each other or cross each other so that the high-temperature airflow is concentrated to form a roasting temperature of 950°C-1100°C. The combustion rack is set up for two rows of burners and is used to install pipes for supplying gas and air. The combustion rack is equipped with several gas branch pipes and air branch pipes for connecting the burners to each burner. The gas station is connected to the gas pipeline on the combustion frame via a pipeline, and the air pipeline on the combustion frame is connected to the air supply mechanism; The main station connects the gas station, combustion chamber, air supply mechanism, and burner to control the operating status of the gas station, combustion chamber, and burner; it is started up using the following method: Step 1) Pre-lay electrolyte blocks or electrolyte powder of a certain height in the electrolytic cell, and hang anode carbon blocks; Step 2) Install the high-energy calcination device for the aluminum electrolytic cell into the electrolytic cell. The inner wall of the electrolytic cell is provided with a refractory fiber layer with a refractory temperature ≥1250°C. Step 3) Insulation: Cover the upper part of the electrolytic cell with electrolyte or cryolite for insulation; Step 4) The main station controls the introduction of gas and combustion air and ignites them to heat the electrolytic cell until the calcination temperature reaches 950°C-1100°C. Step 5) As the electrolyte in the electrolytic cell melts, new electrolyte blocks or electrolyte powder are gradually added. Step 6) When the amount of electrolyte is sufficient and the temperatures of the anode carbon block and cathode carbon block are also sufficient, control the electrolytic cell to start.

2. The electrolytic cell high-energy roast start-up method of claim 1, wherein: The burner is surrounded by refractory fiber material.

3. The method of claim 2, wherein: The air supply mechanism is integrated into the main station.

4. The method of claim 3, wherein: The burner has a split structure, including a combustion chamber and an upper structure. The upper structure includes a gas inlet, an air inlet, a plug, an ignition / observation hole, a positioning plate, and fixing bolts. The gas inlet, air inlet, and ignition / observation hole are all installed on the positioning plate. The plug is located at the top of the ignition / observation hole. The combustion chamber is detachably connected to the upper structure by fixing bolts. The combustion chamber has a nozzle on its inner side.

5. The method of claim 4, wherein: The combustion rack is a pipe structure arranged along pairs of burners.

6. The electrolytic cell high-energy roast start-up method of claim 5, wherein: It also includes temperature sensors, which are distributed in the heating space between the two rows of burners and are connected to the main station.

7. The method of claim 6, wherein: It also includes an oxygen content sensor, which is installed in the burner and connected to the master station.

8. The electrolytic cell high energy roast start-up method of claim 1, wherein: In step 1), the pre-laid electrolyte block or electrolyte powder material extends 180mm-250mm beyond the cathode carbon block.

Images