System and method for manufacture of paper, board or the like

A method for manufacture of paper, board or the like, comprising:

• obtaining a fibre stock comprising fibres originating from recycled fibre material, unbleached kraft pulping and/or unbleached semichemical pulping, whereby the fibre stock has a conductivity of at least 1 mS/cm;
• adding to the fibre stock an aqueous solution of a water-soluble amphoteric polyacrylamide, which is a copolymer obtained by polymerizing (meth)acrylamide and 1-25 mol-% of cationic monomers and 0.1-24 mol-% of anionic monomers, the polyacrylamide having an intrinsic viscosity in a range of 6-38 dl/g determined in 1 M NaCl at 25° C.;
• adding to the fibre stock inorganic microparticles of siliceous material, selected from colloidal silica or bentonite;
• adding to the fibre stock or to an aqueous flow to be combined with the fibre stock a high-charged cationic coagulant having a charge density over 5 meq/g determined at pH 6 and selected from aluminum based coagulants, organic polymers and mixtures thereof;
• and
• forming the fibre stock into a fibrous web.