State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
Bioresour Technol. 2016 Feb;202:165-71. doi: 10.1016/j.biortech.2015.12.006. Epub 2015 Dec 14.
This study investigated the influence of anaerobic granular sludge size on its bioactivity at COD concentration of 1000, 3000 and 6000 mg/L. Based on size, granules were categorized as large (3-3.5 mm), medium (1.5-2 mm) and small (0.5-1 mm). A positive relationship was obtained between granule size and biogas production rate. For instance, at COD 6000 mg/L, large granules had highest biogas production rate of 0.031 m(3)/kgVSS/d while medium and small granules had 0.016 and 0.006 m(3)/kgVSS/d respectively. The results were reaffirmed by applying modified Fick's law of diffusion. Diffusion rates of substrate for large, medium and small granules were 1.67×10(-3), 6.1×10(-4)and 1.8×10(-4) mg/s respectively at that COD. Large granules were highly bio-active due to their internal structure, i.e. big pore size, high porosity and short diffusion distance as compared to medium and small granules, thus large granules could improve the performance of reactor.
本研究考察了厌氧颗粒污泥粒径对 COD 浓度为 1000、3000 和 6000mg/L 时其生物活性的影响。根据粒径大小，将颗粒分为大（3-3.5mm）、中（1.5-2mm）和小（0.5-1mm）三种。结果表明，颗粒粒径与沼气产生速率呈正相关。例如，在 COD 为 6000mg/L 时，大颗粒的沼气产生速率最高，为 0.031m³/kgVSS/d，而中、小颗粒的沼气产生速率分别为 0.016m³/kgVSS/d 和 0.006m³/kgVSS/d。应用修正的菲克扩散定律进一步证实了这一结果。在该 COD 下，大、中、小颗粒的基质扩散速率分别为 1.67×10(-3)、6.1×10(-4)和 1.8×10(-4)mg/s。与中、小颗粒相比，大颗粒具有较大的内部结构，即大孔径、高孔隙率和较短的扩散距离，因此具有较高的生物活性，从而可以提高反应器的性能。
