Feasibility of pyrolysing wastewater sludge for char and energy production is dependent on the usability of the produced sludge char. This study aimed to produce mechanistic information of char impacts on amended porous media by determining (1) pore structure of sludge chars with 3D image analyses and (2) their influence on water retention and shrinkage properties of three contrasting soils. The pore structure of the chars consisted of crevices and large spheres. Their water retention impacts were minor, even though the low-porous char slightly increased porosity in the amended materials in various pore-size ranges. The dominating, though small, impacts were the increase in easily drainable interpores and decrease in smallest pore sizes relevant for plant available water. The char impacts were more visible in fine-than coarse-textured soils. The chars also significantly reduced shrinkage in clay soils. The results were insensitive to sludge feedstock or char particle size.

热解废水污泥用于焦炭和能源生产的可行性取决于所产生的污泥焦炭的可用性。这项研究的目的是通过确定（1）通过3D图像分析确定污泥炭的孔隙结构，以及（2）它们对三种对比土壤的保水率和收缩性能的影响，从而得出炭对改性多孔介质的影响的机理信息。炭的孔结构由缝隙和大球组成。即使在各种孔径范围内，低孔炭在修正材料中的孔隙率略有增加，它们对保水的影响也很小。尽管影响不大，但主要的影响是易于排水的孔的增加和与植物可用水有关的最小孔径的减小。炭的影响在比粗糙结构的土壤中更明显。炭还显着减少了粘土中的收缩。结果对污泥原料或焦炭粒度不敏感。