Abstract: A method of processing oily sludge to remove a substantial proportion of the water and hydrocarbon content therefrom to form a solid cake of waste material that is suitable for disposal in land fill sites. The method involving, firstly promoting flocculation in a batch of waste material by mixing in a flocculating agent. The flocculated waste material is then pressing at a first pressure to extract substantially all the free water within the mixture. After the first pressing the waste material is subjected to a second pressing at a second pressure to extract a substantial proportion of hydrocarbon material and further water from the mixture, thus leaving a solid cake of waste material. The invention also considers additional processing steps to maximize the level of hydrocarbon material reclaimed from the waste material.

Abstract: The invention relates to a process of applying a polyhydroxy high molecular weight polymer or like material to a substrate, comprising adding to a solution of such material in anionic form a flocculent of oppositely charged form in order to insolubilise such material, and thereafter applying such insolubilised material to said substrate. The invention has particular application in respect of production of paper by adding to the slurry supplied in paper production of an anionic starch and a cationic flocculent in predetermined amounts. The cationic polymer is preferably added prior to addition of the anionic starch. The cationic polymer preferably has a molecular weight of 150,000 or more and the anionic starch is preferably added in an amount of from 75% to 125% of the reaction ratio amount. Preferably, the cationic polymer flocculent is added in an amount of 0.5 kg or more per 1,000 kg of paper substrate and the anionic starch showing an amount of 2 kg or more per 1,000 kg of paper substrate.

Abstract: A method for removal of magnetic ink from pulp stock formed from xerographic and laser printed paper waste comprising feeding such pulped paper waste past one or more magnets for removal of all or substantially all of such magnetic ink. The magnetic ink can be removed by capture or deflection techniques. The preferred pulp slurry has a concentration of 4% or less by weight pulp. The preferred magnetic force to be applied utilizes background magnetic fields in excess of 2000 Gauss and a field gradient in excess of 500 Gauss/cm. Also, a method for improving the recyclability of paper waste having ink thereon which does not normally contain a magnetic component, by utilizing one or more magnetic carriers in the formulations of the printing ink utilized.