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 Before filling, the electrode paste shall be broken into 80 ~ 100mm small pieces, so that the electrode paste can pass between the two ribs smoothly. If the particle size is too large, the electrode paste suspension fault is easy to occur; If the particle size is too small, it is easy to cause paste spraying. It is better to buy the finished electrode paste. If the material supplied by the manufacturer is qualified, it can be directly filled. The powder of broken electrode paste is reduced, the utilization rate of electrode paste is improved, and the cost of calcium carbide is reduced. Use a forklift to transport the electrode paste to the carbide furnace with a trolley or special tools, and use an electric hoist to lift the electrode paste into the electrode barrel. Pay attention to lifting * during filling. 　　When installing the electrode paste, pay attention not to scatter the electrode paste on the equipment outside the electrode barrel, so as to avoid the electric ignition a

 Use process and consumption of electrode paste in terms of use characteristics, electrode paste is a continuous self baking electrode. During use, its outer layer is a cylinder made of 1-2mm thick steel plate. The electrode paste is regularly added into the cylinder. With the progress of production, the electrode paste is gradually softened, melted and roasted. During roasting, a large amount of volatiles are released. After entering the conductive clip of the electrode, due to the high-temperature effect, it is from semi coking to complete coking, * and becomes a conductive carbon electrode. The electrode paste is baked into a conductive electrode by various heat of the electric furnace itself, so it is called a self baking electrode. During the working process of the electrode, a section of cylinder is connected to the top of the electrode at regular intervals, and a certain amount of electrode paste is added, and the process is repeated.

 　　The so-called oven drying is an operation that uses heating method to gradually adapt the furnace lining and electrode to charging smelting. Its main purpose is to dry the furnace lining and roast the electrode paste. The quality of oven drying will not only affect the service life of the furnace lining, but also directly affect whether the electric furnace can be put into operation smoothly. Therefore, the oven drying system table should be formulated in detail and strictly implemented in the opening plan. 　　Coke oven 　　There are three methods in the stage of oven drying: wood drying, oil drying and coke drying. This paper only introduces the coke drying. As the name implies, coke baking is a method of baking the furnace by using the combustion heat of coke. Large metallurgical coke with less ash shall be used to make fuel (particle size > 150mm). During the baking of electrode paste, it shall be ensured that the coke burns close to the electrode and is added in time. I

 　　Use process and consumption of electrode paste in terms of use characteristics, electrode paste is a continuous self baking electrode. During use, its outer layer is a cylinder made of 1-2mm thick steel plate. 　　The electrode paste is regularly added into the cylinder. With the progress of production, the electrode paste is gradually softened, melted and roasted. During roasting, a large amount of volatiles are released. After entering the conductive clip of the electrode, due to the high-temperature effect, it is from semi coking to complete coking, * and becomes a conductive carbon electrode. The electrode paste is baked into a conductive electrode by various heat of the electric furnace itself, so it is called a self baking electrode. During the working process of the electrode, a section of cylinder is connected to the top of the electrode at regular intervals, and a certain amount of electrode paste is added, and the process is repeated.

  Compared with hot ramming paste,   cold ramming paste   is characterized by convenient construction and controllable quality. During the construction of hot ramming paste, put the paste in the kneading pot 2-3 hours in advance and heat it to above 110 ℃ to soften the paste. At the same time, heat the   carbon block   group and side   carbon block   placed in the electrolytic cell to about the same temperature before construction. Due to the sensitivity of paste to temperature, each layer of rolling paste is required to be completed in a short time. At the same time, the rolling compression ratio of paste can only be determined through fixed technology and experience. The controllability is poor, resulting in the hidden danger of slot leakage. 　　Since the  cold ramming paste  can be constructed under the normal temperature of 15-35 ℃, it is within this temperature range in the electrolytic plant most of the time in China, even in the northern region. Generally, the new aluminum plant

  　Like   cathode carbon block , the aggregate of cathode paste mainly uses high-quality electric calcined anthracite as raw material. At present, it mainly uses anthracite of high quality in Taixi Town, Ruqigou, Shizuishan City, Ningxia, which is called Taixi Coal. Taixi Coal has the characteristics of “three bottoms and six highs” (bottom ash, bottom sulfur, bottom phosphorus, high calorific value, high specific resistance, high lump coal rate, high chemical activity, high clean coal recovery rate, and high mechanical strength), which is the highest quality coal in China. There are also those who use high-quality electric calcined (generally not using gas calcined) anthracite from other regions as aggregate, but Taixi Coal is the first to be used as aggregate. 　　In Table 1, the paste is divided into two categories: semi graphite and high graphite according to the different graphite content (in some data reports, the high graphite cold rammed paste is made of 25% graphite). In actual

  Cold rammed paste has its own precise density, so in this, we can see that the knowledge learned is actually very rich. No matter from what aspect, the characteristics of cold rammed paste are distributed in the middle. What is the method to determine the height of cold rammed paste? Xiaobian will explain it to you today. 　　The height of Cold ramming paste refers to the height from the upper end of the electrode clamp to the top of the  electrode paste . If the  electrode paste  is too high, the coarse and fine particles in the cold rammed paste are prone to delamination, or the electrode cylinder is swollen due to the pressure of the paste column. If the  electrode paste  column is too low, it is difficult to obtain a dense electrode because the pressure of the paste column is too small and the filling property is poor. The consumption of Cold ramming paste is too fast. The proper height of electrode paste column is conducive to improving the quality of electrode roasting and reduci

  　　In fact, there are many changes in cold mash itself. No matter what kind of texture products, we all need cold mash to play in it. This is the knowledge we want to tell you today. The corresponding change of cold mash is what we want to tell you today. 　　Strength deterioration: according to the test of used carbon bricks and the alkali metal corrosion test of unused carbon brick samples in the laboratory, it is found that the strength of carbon bricks decreases sharply after being corroded by alkali metals. 　　Volume and plastic expansion: it is found that the volume of carbon brick sample expands after alkali metal corrosion test. When the sample is corroded by alkali metal under different loads, it is found that the sample has different degrees of plastic deformation and forms a plastic body according to different loads. 　　Promote graphitization: the chemical test of the used carbon brick found that the thermal conductivity of the carbon brick increased after being eroded by the a

  A cathode paste that can be built at room temperature. The aggregate of this cathode paste is the same as that of ordinary cathode paste (also known as hot ramming paste), such as common calcined anthracite or electric calcined anthracite, metallurgical coke, graphite chips, etc. The low softening point of the binder is 20 ℃± 5 ℃. 　　Cold rammed paste has low softening point and high volatile content. It should be packed in woven bags and plastic bags with a shelf life of 6 ~ 9 months. The construction temperature of Cold ramming paste is 25 ~ 50 ℃, and it can be constructed under the ambient temperature in summer: stewing paste can be used to make up for the impact of low ambient temperature in spring and autumn. The stewing temperature is 40 ~ 50 ℃. Furnace building in northern winter will affect the masonry quality and the service life of the trough. 　　Before the 1970s, the hot ramming paste or aluminum electrolytic cell used in China’s aluminum industry borrowed the coarse seam pa

  　In order to maintain good air permeability in the furnace, the requirements for tamping in the ferrosilicon smelting process are very strict. Under the principle of not damaging the crucible, tamping should be quickly penetrated. New materials or additional coke should be added in time along the tangent direction of the electrode during tamping to reduce heat loss. 　　Ramming furnace is to flip over the sintering area with large pieces of furnace charge and charge surface bonded inside, so as to increase the permeability of charge surface, expand the crucible, and speed up the chemical reaction in the furnace. 　　During ferrosilicon smelting, silica still has great cohesiveness at high temperature. If the furnace is not tamped in time, it will affect the permeability, cause stabbing fire, shrink after drying, and slow down the reaction speed and cooling speed in the furnace. Obviously, furnace tamping is an important operation to increase the permeability of the charge surface and exp

  Classification and properties of cathode pastes for aluminum electrolysis 　　The function of aluminum reduction cell paste is to fill the space between the single  cathode carbon block s laid on the bottom of the cell and between the  cathode carbon block s and the side  carbon block s. After roasting, the bottom and side of the cell form a complete sealed cell body, so as to avoid the leakage of electrolyte and aluminum liquid during roasting and operation; At the same time, as a part of the cell, it can balance the heat generated in the electrolysis process with the heat lost at the side, so as to improve the electrical efficiency and prolong the service life. 　　At present, the electrolytic cell capacity has entered the super large era of 400ka-600ka. The annual production capacity of a single series is more than 400000 tons. The investment is huge, and the requirements for furnace building, operation and management of the electrolytic cell are higher. The paste is the fatal materia

  1. Do not squeeze during loading and transportation, and avoid tamping in advance. 　　2. The storage conditions shall be normal temperature, away from light and wind. 　　3. The storage time of cold rammed paste should not be too long, and the shelf life is generally within one year, so as to avoid the drying of paste caused by the evaporation of binder. Using expired or relatively dry  cold ramming paste  may cause stratification and uneven quality during construction, increasing the risk of slot leakage during roasting and operation. 　　Conclusion: Cold ramming paste is valued and applied by aluminum electrolysis enterprises because of its convenient construction, excellent and controllable quality, little damage to workers’ health, reduced investment in equipment plants and labor saving in construction. In the production of Cold ramming paste, it is recommended to use high-quality Taixi electric calcined anthracite and specially refined high-quality binder as raw materials. The raw ma

 Coke is one of the most important raw materials for making electrode paste, especially graphitized electrodes. The most valuable coke is low-ash coke (sometimes called ash-free coke), and its ash content does not exceed 1%. These cokes include petroleum coke and pitch coke. The first type is coke obtained by coking petroleum residue, and the second type is coke produced by processing coal pitch in a chemical coking industrial furnace. The solid carbon-containing product obtained by high-temperature treatment of petroleum residue is called petroleum coke. Due to the different raw materials and production methods, the content of these products is also different. At present, there are two types of petroleum coke with different properties, one is kettle-type petroleum coke, and the other is delayed coking petroleum coke. The former contains 3 to 7% of volatile matter, and the latter contains 10 to 18% of volatile matter. The residue obtained by coking coal tar pitch in the same coke oven

 70% of aluminum electrolytic cell failures occur in pre-baked anodes. Anode failures that often occur in electrolyzers include: partial overheating of the anode, uneven current distribution, anode dropout, anode long bag, anode crack fault, anode block shedding, a large amount of carbon slag falling into the electrolyte to make it carbon-containing, oxidation and combustion around the anode, and The anode is tilted and so on. These failures are mainly caused by the quality of pre-baked anodes and improper electrolysis operations. 1. The anode drops off. The pre-baked anode may cause the anode carbon block to separate from the steel claw due to the poor casting of the phosphorus pig iron or the defect of the anode carbon bowl. When this phenomenon occurs, it is necessary to remove the carbon anode from the electrolytic cell and replace it with a new pre-baked anode. When the anode carbon block has large cracks, the block will also be cracked. 2. Long anode bag. Due to the uneven intern

 1. Calcining. Both petroleum coke and pitch coke need to be calcined, and the calcining temperature should reach 1350. C, to fully remove the volatile matter contained in the carbonaceous raw materials, and improve the true density, mechanical strength, and conductivity of the coke. 2. Crushing, screening and batching. The calcined carbonaceous raw material is crushed and sieved into aggregate particles of specified size, part of the coke is ground into fine powder, and then weighed according to the formula to form a dry mixture of various particles. 3. Kneading. Under the heating state, the quantitative dry mixture of various particles and the quantitative binder are stirred and mixed and kneaded to form a plastic paste. 4. Forming. Under the action of external pressure or high-frequency vibration, the paste is pressed into a green electrode with a certain shape and higher density. 5. Roasting. Put the green electrode in a special roasting furnace, and use metallurgical coke powder t

 Electrode paste is also called self-baking electrode. It is a kind of semi-finished electrode material made of electric forging coal, residual electrode, etc. as aggregate, and asphalt, tar, etc. as binder. In the process of use, the electrode paste needs to be injected into the submerged arc furnace. When it is heated to about 400 degrees, the electrode paste melts and then completes sintering to become a solid. When it is heated to 800 degrees, the arc combines with the original ore to generate huge heat to complete the ore Smelting. The so-called airtight paste is only for the type of submerged arc furnace. Submerged arc furnace is divided into closed type, semi-closed type and open type. These different types of submerged arc furnaces use electrode pastes. Because of the different furnace types, over time, the electrode pastes applied to closed submerged arc furnaces are called closed electrode pastes, or closed pastes for short; they are used in open or semi-closed arc furnaces.

 Nickel-iron electrode paste has always been regarded as a high-end product in the electrode paste market. For a long time, the formula of nickel-iron electrode paste has been a mystery. At present, there are only a few electrode paste factories that can produce high-standard sealed electrode pastes that meet the needs of ferronickel production. The formula of the nickel-iron high-standard airtight paste is the same as that of the ordinary national standard electrode paste, and the raw material ratio is different. The terminal price of the electrode paste processed by our factory for a trading company to one of the largest alloy plants in Asia in Jiangsu is close to 4,000 yuan/ton. The price of ordinary electrode paste is only between 3000-3500. The raw materials of nickel-iron smelted electrode paste are indeed a little higher than the cost of ordinary electrode paste. Regarding the amount of electrode paste, our factory's high-standard sealed paste reaches 8-10kg/ton of nickel-ir

Application of submerged electric furnace using high-standard closed paste electrode paste (self-baking electrode) in ferronickel production Production and capacity development The main equipment for smelting closed paste nickel pig iron using laterite mines in my country is the electrode paste submerged arc furnace. Next is the blast furnace. In 2012, the output of nickel-containing pig iron physical alloys has reached 5.201 million tons according to private statistics. The output of medium and high nickel pig iron solid alloys with high-standard closed paste nickel pig iron containing more than 4% nickel was 3.95 million tons. The ferroalloy electrode paste submerged thermal equipment produced in my country is undergoing a large-scale transition from a capacity of 6300kva to a capacity of 25000-66000kva. At present, most of the electrode paste electric furnaces with a capacity of 12500-33000kva are used. The profit situation of the recent production of ferronickel products is e

Crushing and screening Laterite ore has low nickel content and uneven lumpiness. The particle size is finer, and there are also large blocks with a particle size of more than 100 millimeters. It is necessary to consider the installation of cone, jaw crusher or counter-roll crusher and screening equipment, so that the high-standard closed paste electric furnace ore and other charge can meet the technical requirements of use. Pre-drying Laterite ore imported from Indonesia and the Philippines usually contains 32-40% moisture. About 20% of the physical water should be dried at 120°C for 2 hours to remove. Use closed paste submerged arc furnace, hot blast stove, rotary furnace hot flue gas to dry laterite, blast furnace or closed submerged arc furnace gas or to strengthen production equipment (7-8% crystalline water, decomposed and removed at 400℃, after half an hour.) Block The powdered red clay is sintered, pelletized, and briquetted into the electrode paste submerged arc furnace, w

The electrode is the only channel for the electric furnace to input electric energy, and it can also be said to be the heart of the electric furnace. Therefore, making the electrode have good working conditions is the key to the successful opening of the furnace. Large-scale submerged arc furnaces generally use self-baking electrodes. Self-baking electrodes use anthracite, pitch, etc. as raw materials to make electrode paste at a certain temperature, and then put the electrode paste into the installed electrode shell and then sinter and coke. . Therefore, to make a reasonable oven system, it is necessary to understand the sintering characteristics of the electrode paste. Sintering process of Rongxin carbon electrode paste self-baking electrode The self-baking electrode sintering process is a process in which the binder decomposes and gradually discharges volatiles as the temperature increases. The sintering of the electrode can be roughly divided into three stages. The first stage