麦草化学机械制浆预处理方法研究

Study on Pretreatment Method of Chemi-mechanical Pulping of Wheat Straw

使用麦草原料制取漂白化学机械浆,为了后续多段漂白能够获得高白度的纸浆,研究了3种不同的化学药品用于预浸渍阶段对未漂白浆的光学和物理性能的影响,包括成浆白度、成浆强度指标、纤维筛分级分,并比较了磨浆的比能耗和废水污染负荷。研究结果表明,与碱性过氧化氢(2.0% NaOH、1.5% H2O2、0.4% DTPA)处理(P工艺)磨浆相比亚硫酸钠(2.0%Na2SO3、2.0%Na2CO3、0.4%DTPA)预处理(S工艺)磨浆比能耗降低了33%,果胶酶(10IU/g以绝干浆计)/碱性过氧化氢(2.0%NaOH、1.5%H2O2、0.4%DTPA)预处理(Pe/P工艺)也可以降低磨浆比能耗10%,P工艺预处理与S工艺预处理均能提高成浆白度,Pe/P工艺预处理成浆呈现暗红色;P工艺预处理成浆物理强度高于其他两种浆;S工艺预处理磨浆段废水化学耗氧量(COD)发生量较高,达到84.09kg/t(以绝干浆计)。

Bleached chemi-mechanical pulps from wheat straw were produced. In order to get pulp of high brightness during multiple-stage bleaching, investigations were carried out on influences of impregnation using different chemicals, on optical and physical properties of unbleached chemi-meehanieal pulps, such as coarse pulp brightness, coarse pulp strength, fiber screen classi- fication, specific energy consumption of refing process and COD load of effluent generated by pulping process. Results showed that specific energy consumption of straw chips treated by sodium sulfite （ S method ; 2.0 % Na2SO3 , 2.0 % Na-2CO3 , 0.4 % DTPA） is reduced by 33 % , comparing with that treated by alkaline peroxide （ P method; 2.0 % NaOH, 1.5 % H202, 0.4 % DTPA）. Specitic refining energy consumption of straw chips treated by pectinase （ 10 IU/g oven. dry pulp）/alkaline peroxide （Pe/P method; 2.0 % NaOH, 1.5 % H202 ,0.4 % DTPA）can be reduced by 10 % ; Both P method and S method can improve pulp brightness, while pulp pretreated by Pe/P method presents wine colour. Better physical strength of pulp is obtained using P method, comparing with other two kinds of pulp; The COD load of effluent generated by refining process after S pretreatment is 84.09 kg/t （based on o.d. pulp）.