Avantha Centre for Industrial Research & Development, Paper Mill Campus, Yamunanagar, Haryana, India.
Department of Environmental Science & Engineering, Guru Jambheshwar University of Science & Technology, Hisar, Haryana, India.
Environ Sci Pollut Res Int. 2017 Oct;24(30):23488-23497. doi: 10.1007/s11356-017-9965-6. Epub 2017 Aug 28.
Environmental degradation by industrial and other developmental activities is alarming for imperative environmental management by process advancements of production. Pulp and paper mills are now focusing on using nonwood-based raw materials to protect forest resources. In present study, rice straw was utilized for pulp production as it is easily and abundantly available as well as rich in carbohydrates (cellulose and hemicelluloses). Soda-anthraquinone method was used for pulp production as it is widely accepted for agro residues. Bleaching process during paper production is the chief source of wastewater generation. The chlorophenolic compounds generated during bleaching are highly toxic, mutagenic, and bioaccumulative in nature. The objectives of study were to use oxygen delignification (ODL) stage prior to elemental chlorine-free (ECF) bleaching to reduce wastewater load and to study its impact on bleached pulp characteristics. ODL stage prior to ECF bleaching improved the optical properties of pulp in comparison to only ECF bleaching. When ODL stage was incorporated prior to bleaching, the tensile index and folding endurance of the pulp were found to be 56.6 ± 1.5 Nm/g and 140, respectively, very high in comparison to ECF alone. A potential reduction of 51, 57, 43, and 53% in BOD, COD, color, and AOX, respectively was observed on adding the ODL stage compared to ECF only. Generation of chlorophenolic compounds was reduced significantly. Incorporation of ODL stage prior to bleaching was found to be highly promising for reducing the toxicity of bleaching effluents and may lead to better management of nearby water resources. Graphical abstract ᅟ.
工业和其他发展活动造成的环境退化，迫切需要通过生产过程的进步来进行环境管理。制浆造纸厂现在专注于使用非木材基原料来保护森林资源。在本研究中，利用水稻秸秆作为制浆原料，因为它易于获得且丰富，并且富含碳水化合物（纤维素和半纤维素）。由于该方法广泛适用于农业废弃物，因此采用苏打-蒽醌法进行制浆。在造纸过程中，漂白过程是产生废水的主要来源。在漂白过程中产生的含氯酚类化合物具有高度毒性、致突变性和生物累积性。本研究的目的是在无元素氯（ECF）漂白之前使用氧脱木质素（ODL）阶段来减少废水负荷，并研究其对漂白浆特性的影响。与仅进行 ECF 漂白相比，在 ECF 漂白之前进行 ODL 阶段可改善纸浆的光学性能。当在漂白之前加入 ODL 阶段时，与仅进行 ECF 漂白相比，纸浆的拉伸指数和耐折度分别提高到 56.6 ± 1.5 Nm/g 和 140，非常高。与仅进行 ECF 漂白相比，添加 ODL 阶段可分别将 BOD、COD、颜色和 AOX 的去除率降低 51%、57%、43%和 53%。显著减少了含氯酚类化合物的生成。在漂白之前加入 ODL 阶段，对于降低漂白废水的毒性非常有希望，并可能导致对附近水资源的更好管理。
