Study On Agglomeration-Magnetic Removing Stickies Of Mixed Office Waste Paper

Mixed office waste paper has become the growth point in the secondary fiber recycling.However,the contaminations of non-contact printing inks and stickies in the fibers usually causes trouble in the recovering process.In the this paper,the octadecanol was used,by adding magnetite,to agglomerate the ink and stickies in waste paper,and these contaminations was removed by magnetic separation.Through using the single factor method experiment,the various factors on the agglomeration-magnetic separation process had been discussed. And by the use of pressure sensitive adhesive model,the effect of agglomeration on the stickies,and also the basic tenets of agglomeration by SEM,FTIR analysis had been studied.The results show that:Magnetite particle size,as well as the stirring speed of the agglomerating process are very effective at agglomertating inks.Best agglomeration process parameters for mixed the office waste paper is that:the agglomeration temperature is 70℃,and octadecanol content is 2%,magnetite particle size is mesh of 60-80,with the stirring speed of 800 r/min,and agglomerating 60 min, during the agglomeration pulp concentration is 4%,centrifugal magnetic separation concentration is 1%,by centrifugaling 30 min.As a result,99%ink removal rate has been obtained,with less than 0.18%of DCS in the deinked pulp.The presence of sodium hydroxide has a negative role in the process,and agglomeration-magnetic separation method is a neutral approach,eliminating the degradation of fiber caused by sodium,as well as environmental problems.FTIR spectra shows that the absorption strength of the ink and adhesive in deinked pulp after agglomeration-magnetic separation,decreases significantly. Octadecanol has strong wetting action on inks and stickies,as well as the images of SEM showes that through "liquid bridge" role,octadecanol connects inks and stickies together,forming agglomerates,similar to balls,in the "enbedding" state.