Anaerobic digestion of recycled paper crumb and effects of digestate on concrete performance
Anaerobic digestion of recycled paper crumb and effects of digestate on concrete performance
复制标题
DOI：
10.1016/j.renene.2023.03.061
复制
发表时间：
2023-03
期刊：
影响因子：
8.7
通讯作者：
G. Hurst;Ash Ahmed;Steven Taylor;S. Tedesco
中科院分区：
文献类型：
--
作者：
G. Hurst;Ash Ahmed;Steven Taylor;S. Tedesco
纸屑（PC）是废纸回收行业产生的一种造纸污泥残留物。它是来自各种纤维纯化阶段的副产物，特别是由短纤维素纤维、木质素、有机化合物和无机填料残留物组成。尽管这种原料是纸张回收部门的废弃物，但它可以变成一种生物资源，以更可持续的混凝土形式实现跨部门的工业共生，从而为新型净零供应链提供机会。本研究试图通过连续厌氧消化从有机化合物中产生甲烷（CH 4），然后利用碳酸盐作为混凝土中的水替代物来提高PC的价值。21天的消化PC产生163毫升CH 4每克挥发性固体和由此产生的碳酸盐状态改善混凝土的抗压强度高达50%的水置换等级，满足要求的结构级（C32/40）的应用与取代等级高达50%和25%，分别与和没有添加增塑剂。在一个小的能力，减少了混凝土拌合物的和易性，但我们证明他的问题可以通过添加增塑剂或增加混凝土与水的比例来解决。外加剂的添加对于促进现场的可泵性和确保令人满意的压实是重要的。这项研究强调了厌氧消化作为混凝土补充剂（添加剂）的潜力，这将提高建筑和造纸行业的可持续性。
Paper crumb (PC) is a type of paper sludge residue from the wastepaper recycling industry. It is a by-product from the various fiber purification stages that is particularly composed of short cellulose fibers, lignin, organic compounds and inorganic filler residues. Despite representing a reject material for the paper recycling sector, this feedstock can be turned into a bioresource to enable cross-sector industrial symbiosis in the form of a more sustainable concrete, hence an opportunity for novel Net Zero supply chains. This study sought to valorise the PC by the sequential anaerobic digestion to produce methane (CH4) from the organic compounds, followed by utilization of the digestate as a water replacement in concrete. The 21-day digestion of PC yielded 163 ml CH4per gram volatile solids and the resulting digestate improved concrete compressive strength up to 50% water replacement grade, meeting the requirements structural grade (C32/40) applications with substitution grades up to 50% and 25% with and without the addition of plasticiser respectively. In a minor capacity, the digestate reduced workability of the concrete mix, however we demonstrate his issue can be resolved by the addition of plasticiser or increased concrete to water ratios. The admixture addition is important to facilitate pumpability on site and ensure satisfactory compaction. This study highlights the potential of anaerobic digestion digestate as a concrete supplement (additive), which would improve the sustainability of both the construction and the paper sector.