Development Of New Copper Release Agent And Industrial Application Research

In this paper,we are aiming to improve and optimize the release agents used for anode copper casting mold.This work is based on the technology-development project named "study and application of new release agent for copper anode casting",signed and conducted corporately by Yunnan Copper Industry Co.,Ltd.and Kunming University of Science and Technology Industry Management Co.,Ltd,to complete laboratory studies,semi-industrial and industrial tests of technical route for new release agents.Laboratory studies contain the effect of adhesion and sintering ability on the using of release agent.In details,the factors affecting adhesion are as below:polar adaptability of release agents with copper mold surface,the more adaptation of polarity,the stronger adhesion;while the greater cohesion of release agents,the worse adhesion;a smaller difference of thermal expansion coefficient between release agents with copper,the smaller volume shrinkage,the better adhesion;the greater the surface tension and worse wetting ability,the lower adhesion.The factors affecting sinter ability of release agent comprise crystal structure of release agents,the dispersion of materials,addition of low-melting eutectic,sintering temperature and sintering time.Semi-industrial tests carried out the studies of effects of additives,additives size,liquid to solid ratio of new release agent on the release agents,finally determined the novel composition of release agents and technology roadmap,which uses barium sulfate as main body and adds boron oxide,aluminum oxide and calcium oxide,then by partial sintering during the high-temperature copper casting,to forms an effective integrated layer of protective film to cover the surface of the mold,avoid the anode plate sticky board and reduce remaining release agents attached to the board after anode plate taken.New release agents contain barium sulfate about 30%-60%,no more than 10%boron oxide,10%-30%aluminum oxide and 10%-30%calcium oxide.Industrial tests finalize mass composition of the new release agent:50%barium sulfate,10%boron oxide,35%silicon oxide,2%alumina oxide and 3%calcium oxide.The particle size of barium sulfate is 1000-1200 mesh,the each additive component after grinding,drying and sieving reaches 150-200 mesh.The liquid to solid ratio is 2:1 with water.Then 6 tons of release agents were prepared according to this proposal,after 30-days industrial test and completion of casting work of 3000 tons copper anode,10910 anode plates were obtained totally.Application of new type release agent:for the anode board rate of 2%,5%,porosity 4%-10%,anode plate glue board rate of 0.5%,1%,scrap rate of 1%-1%.Achieved compared with the traditional barium sulfate tuomoji,whiteboard rate fell 18-25%,porosity by 4%-10%,anode plate glued board rate fell by 2.5%-2.5%,scrap rate fell by 1.5%-3%.Tracking electrolysis results of anode plate after casting shows the proportion of pores and the presence of new mold release have significant impact on the electrolysis.The presence of pores can lead to perforation of the anode plate then increase anti-refining rate of damaged poles,while the light component in release agent will cause the crystallization at the surface of cathode plate and formation of a sandwich plate due to the remnants of mold release agent in the anode plate during the electrolysis..Complete economic accounting of industrial test shows that using the new release agent can reduce cost of 3.56 million yuan per year under the same circumstances of production tasks.