A method for high intrinsic viscosity pulp production, comprising: pre-hydrolyzing raw material in a digester via steam heating, the raw material comprising hardwood chips, including performing pre-hydrolysis kraft process cooking of the hardwood chips in the digester via steam heating to obtain a pre-hydrolysis condition comprising a P factor from 10 to 30; adding a white liquor pad to the cooked hardwood chips, wherein the white liquor pad comprises 0% to 5% of a weight of the hardwood chips; pre-heating a non-purified cold caustic extraction filtrate having a filtrate concentration of between 40 gEA/l and 60 g EA/l to a filtrate temperature of between 120 °C and 130 °C adding non-purified cold caustic extraction filtrate to produce alkali impregnated cooked hardwood chips; heating the alkali impregnated cooked hardwood chips to reach a target temperature between 140 °C and 150 °C and holding for a cooking time to reach a target H-factor corresponding to a kappa number between 16 and 18 and produce pulp; displacing cooking liquor with a cold wash liquor comprising residual alkali at concentration higher than 2 gEA/l until the pulp is below boiling conditions; discharging the pulp from the digester to at least one of an atmospheric discharge tank, atmospheric washing equipment, and pressurized washing equipment; washing the pulp; screening the pulp; adding cold fresh alkali, comprising NaOH, white liquor, or both, to the pulp for cold caustic extraction to operate at an extraction temperature of between 30 °C and 35 °C for an extraction time of between 15 and 30 minutes; performing counter current washing of the pulp at a washing temperature of between 50 °C and 85 °C to recover the cold caustic extraction filtrate; and bleaching the pulp in a high selective bleaching sequence comprising a three stage ECF sequence to yield a final pulp having intrinsic viscosity > 1200 ml/g, alpha cellulose content > 94%, and brightness of between 89% and 91% ISO, wherein the bleaching includes at least one of a magnesium salt and a chelating agent; dewatering the pulp; pressing the pulp; drying the pulp; and forming the pulp into rolls or bales. pre-hydrolyzing raw material in a digester via steam heating, the raw material comprising hardwood chips, including performing pre-hydrolysis kraft process cooking of the hardwood chips in the digester via steam heating to obtain a pre-hydrolysis condition comprising a P factor from 10 to 30; adding a white liquor pad to the cooked hardwood chips, wherein the white liquor pad comprises 0% to 5% of a weight of the hardwood chips; pre-heating a non-purified cold caustic extraction filtrate having a filtrate concentration of between 40 gEA/l and 60 g EA/l to a filtrate temperature of between 120 °C and 130 °C adding non-purified cold caustic extraction filtrate to produce alkali impregnated cooked hardwood chips; heating the alkali impregnated cooked hardwood chips to reach a target temperature between 140 °C and 150 °C and holding for a cooking time to reach a target H-factor corresponding to a kappa number between 16 and 18 and produce pulp; displacing cooking liquor with a cold wash liquor comprising residual alkali at concentration higher than 2 gEA/l until the pulp is below boiling conditions; discharging the pulp from the digester to at least one of an atmospheric discharge tank, atmospheric washing equipment, and pressurized washing equipment; washing the pulp; screening the pulp; adding cold fresh alkali, comprising NaOH, white liquor, or both, to the pulp for cold caustic extraction to operate at an extraction temperature of between 30 °C and 35 °C for an extraction time of between 15 and 30 minutes; performing counter current washing of the pulp at a washing temperature of between 50 °C and 85 °C to recover the cold caustic extraction filtrate; and bleaching the pulp in a high selective bleaching sequence comprising a three stage ECF sequence to yield a final pulp having intrinsic viscosity > 1200 ml/g, alpha cellulose content > 94%, and brightness of between 89% and 91% ISO, wherein the bleaching includes at least one of a magnesium salt and a chelating agent; dewatering the pulp; pressing the pulp; drying the pulp; and forming the pulp into rolls or bales.