Method for preparing blocky graphite anode with high density and low resistivity in short process

Abstract

The invention relates to a method for preparing a blocky graphite anode with high density and low resistivity in a short process, which comprises the following main technological processes: selecting and using excellent needle coke; adding little graphite, crushing and evenly dry-mixing; adding modified asphalt and kneading at a certain temperature; tamping, vibrating and temperature mold-forming; then roasting and carrying out dipping-roasting to increase the strength and intensity of the product; and finally graphitizing to lower electrical resistivity and obtain the finished product. The method for manufacturing the blocky graphite anode with high density and low resistivity in the short process has the advantages of: short cycle of preparing process and low preparing cost; the prepared graphite anode has high density, low resistivity, a fine and even internal structure, small ash content and high mechanical intensity and thermal shock resistance.

Description

【Technical field】 [0001] The invention relates to the technical field of graphite anodes, in particular to a method for preparing a short-flow, high-density, low-resistance bulk graphite anode. 【Background technique】 [0002] The block graphite anode for molten salt electrolysis is a new type of tool material in the non-metallic field. The graphite anode requires high purity, good oxidation resistance, and low pressure drop in order to reduce energy consumption and other production costs and increase production capacity. Graphite materials are required to have high density, low resistivity, low ash content, fine and uniform internal structure, high mechanical strength and thermal shock resistance. [0003] The traditional preparation method of block graphite anode is to use petroleum coke and medium temperature pitch as raw materials, after vibration molding or extrusion molding, and then through roasting, impregnation, graphitization and other processes. The block density ...

AI Technical Summary

Problems solved by technology

Due to the large thickness of the square graphite block, in the preparation process, the roasting process, impregnation process, and graphitization process all need to be strictly controlled and operated, and a longer roasting graphitization temperature rise curve is adopted, and processing and assembly are required at the end, which improves the production efficiency. The production cycle, and because the physical and chemical properties of graphite blocks are not completely uniform, graphite anodes with poor performance are prone to cracks during use

Using petroleum coke as raw material, the prepared graphite anode has high resistivity and high ash content, which leads to increased energy consumption and reduced product purity during use.

However, medium-temperature asphalt is used as the binder, the carbon residue rate is low, and the product strength is low. In order to increase the bulk density, it is necessary to increase the number of dipping and roasting

The graphite anode made by the above method has low strength, high resistivity and poor oxidation resistance

Due to the need to increase the number of dipping and roasting, the production cycle is long and the energy consumption is high, which seriously restricts the production of graphite anodes in my country's carbon industry.

The new preparation process of bulk graphite is hot pressing. For example, Chinese patent application number 200410012433.5 relates to a preparation method of high thermal conductivity graphite material. Difficult to be widely used

Images