Sulfate pulping process with addition of Na2SO3

The invention discloses a sulfate pulping process with addition of Na2SO3, which includes: 1) raw material preparation: employing wood sheet being a raw material; 2) cooking: feeding the wood sheet into a vertical cooking pot, adding cooking white liquid after alkali recovery treatment, wherein the material-to-liquid ratio of the wood sheet to the cooking white liquid is 1:3-4.2, alkali use amountis 15-18%, sulfurization degree is 29-35%, and the use amount of the Na2SO3 is 2-8% of the alkali use amount; 3) screening and washing: blowing out the pulp, screening out knots, and washing the pulpand storing the pulp in a pulp tank; 4) post-treatment: according to production demands, performing slight bleaching on the pulp in the pulp tank and sending the pulp to a papermaking workshop for use. The process overcomes the defects of low pulp yield and deep pulp color in a sulfate process in the prior art. The pulping method is high in pulp yield and is light in pulp color. 本发明公开了种添加亚硫酸钠的硫酸盐制浆工艺，包括以下步骤：(1)备料：采用木材片作为原