METHOD OF MAKING PAPER PROCESS FOR PRODUCING COKES OF LARGE LUMP SIZE AND STRENGTH FROM BITUMINOUS COALS

摘要

1426897 Paper manufacture CALGON CORP 9 July 1973 [12 July 1972] 32564/73 Heading D2B The retention of inorganic filler and fibre fines and the drainage rate are improved during the manufacture of paper by adding to the aqueous pulp finish, prior to dewatering, a water soluble polymer containing 0.5 to 100 mole % of units of the formula (I) and/or of the formula (II) wherein R 1 , R 2 may each be a C 1-18 alkyl group or a C 7-10 aralkyl group, or R 1 and R 2 may be combined with the attached nitrogen atom to form a heterocyclic group; R 3 is hydrogen, halogen or a C 1-4 alkyl group; R 4 is hydrogen halogen or a C 1-5 alkyl group; R 5 is a C 2-4 alkyl group, a phenyl group, or a phenyl group substituted with alkyl and/or alkoxy groups; or R 3 or R 4 may be combined with R 5 to form a cyclic group of at least 6 carbon atoms or a bicyclic group of at least 7 carbon atoms, which cyclic group may be substituted with a C 1-5 alkyl group; R 6 is hydrogen or methyl, R 2 is a group capable of quaternising the nitrogen, X is an anion, and n is 0, 1 or 2. The polymer may also contain 0 to 99.5 mole % of units of the formula (III) and units of the formula (IV) where A is OSP-/SP MSP+/SP or -NH.CH(CH 3 ) 2 .CH 2 SO 3 M and M is hydrogen, ammonium or alkali metal the ratio of the number of units of formulae (I) and (II) to the number of units of formula (IV) being 0.1 to 100. The polymer may also contain up to 20 mole % of other water soluble comonomers such as methacrylamide, methacrylic acid, N alkyl substituted acrylamides and methacrylamides, N- vinyl pyrrolidine and dialkyl diallyl ammonium chlorides, and up to 10 mole % of water insoluble comonomers such as vinyl acetate, acrylonitrile, vinyl chloride, lower alkyl esters of acrylic and methacrylic acids, styrene, and diacetone acrylamine. R 2 may be hydrogen, benzyl, phenethyl, cyanoethyl or alkyl or aralkyl of 1 to 16 carbon atoms. X may be chloride, alkosulphate, tosylate, carboxylate, sulphonate, sulphate, phosphate, acetate or nitrate. M may be sodium or potassium. In the preferred polymers, R 1 , R 2 , R 3 , R 4 , R 5 and R 2 are methyl, R 3 and R 6 are hydrogen, n is 0 or 1 and X is chloride. The molecular weight of the polymer is preferably at least 100000 and the dosage of the polymer may be 0.01 to 7 1bs of polymer per ton of dry pulp. The polymers are effective over a pH range of 4 to 9. The polymer may be added as a powder or a suspension, but is preferably added as a 0.1 to 1 % by weight solution. In example 1, the effect on clay retention is illustrated using a hardwood/softwood kraft pulp which may contain rosin, alum and clay as additives. In example 2, the effect on drainage performance is illustrated using a rebroked waste news/ waste corrugated furnish.