Formulation of Product Formula in Electrode Paste Production

The so-called "recipe" refers to the ingredient formula (or ingredient list) prepared by several kinds of solid raw materials and binders with different properties and different particle sizes in a certain proportion (referred to as the ratio), referred to as the formula. According to the conditions of use, carbon products are required to have various performances. Therefore, it is necessary to select various raw materials according to the performance, and to coordinate their dosage and particle size, so that the characteristics of various raw materials can be used in the product to complement each other. In order to achieve the required performance of the product. The process of combining one or several solid raw materials with different properties and different particle sizes and binders in a certain proportion is called batching. Obviously, batching is an important process in the production process of carbon products.

????Generally speaking, the ingredients of carbon products include the following three aspects:

????① Select the type of carbon raw material and determine the proportion of different types of raw materials used;

????② Determine the particle size composition of solid carbon raw materials, that is, the use ratio of different sizes of particles;

????③Determine the type, performance and dosage of the binder.

????When formulating the formula, the types of raw materials should be reasonably selected according to the use and specifications of the product, and the optimal ratio and particle size ratio should be drawn up to achieve the optimal organizational structure of the product. According to the type of raw material, particle size ratio and powder surface properties, the appropriate binder and its ratio should be selected so that the powder particles of the product have the best bonding performance.

????It is worth noting that although many researchers have done a lot of research on the theoretical calculation of the formula and summed up some theoretical formulas, they have not been able to obtain satisfactory results for the formula calculation. The current production formula is gradually summed up after long-term production practice. Carbon production is very empirical. Therefore, it is better to use the method of combining theoretical calculation and experiment to formulate a new formula. Theoretical calculation can make the experiment organized and systematic, so that the experiment will not lose its direction, but the best formula can only be determined through repeated practice, summary and change. In addition, in actual production, when the raw materials used change, the particle size composition of the aggregate and the type and amount of binder should also be adjusted accordingly. If the production process and equipment change, the formula should also be changed accordingly. Can't be rigid.

????The production formula of electrode paste products mainly refers to the combination of dry materials, which is an important part of the electrode paste formula. The choice of raw materials as fine powder has a direct impact on the quality of electrode paste. The large, medium and small particles in the aggregate should be properly matched to increase the bulk density. The purpose of controlling the composition of the particle size is to obtain a self-baking electrode with compactness, high strength and good conductivity after firing. The amount of powder added should match the amount of binder added, so that the plasticity of the electrode paste is within a specified range, which can not only blend with each other to fill the entire electrode cylinder densely, but also avoid stratification due to too easy flow. If the amount of binder is too much, the sintering speed of the electrode paste cannot keep up with the consumption speed, it is prone to soft breakage, it is not easy to sinter, and it is easy to cause delamination of solid particles and binder. If the amount of binder is low and the electrode paste is sintered too quickly, over-baking will occur, resulting in poor inter-particle bonding, poor compactness, high porosity, and low strength, resulting in easy oxidation, high consumption, and easy electrode hard breakage ACCIDENT.

????In addition to the determination of the proportion of various carbon raw materials, the formula must be accurately proportioned in production. In carbon production, after the powder is prepared, various raw materials and other materials of various particle sizes need to be proportioned according to the formula. The proportioning operation In fact, it is a weighing operation. Obviously, whether the ingredients can be accurately formulated according to the formula, weighing is the key, and whether the weighing is accurate or not will have an impact on product quality and production process. For example, inaccurate weighing of materials of various particle sizes will affect the bulk density of dry materials, that is, destroy the most compact packing of materials, and at the same time affect the amount of binder added.