Attarbachi Taha, Kingsley Martin, Spallina Vincenzo
Department of Chemical Engineering, University of Manchester, M13 9PL Manchester, United Kingdom.
Argent Energy Ltd., CH65 4BF Ellesmere Port, United Kingdom.
Ind Eng Chem Res. 2024 Mar 11;63(11):4905-4917. doi: 10.1021/acs.iecr.3c03868. eCollection 2024 Mar 20.
The purification of waste-derived crude glycerol to the 2000 g scale is presented to provide a consolidated proof of concept. Starting from unprecedented low-quality glycerol from a second-generation biodiesel plant, currently disposed of at cost, a series of physiochemical steps are implemented to improve glycerol purity and recovery under relevant conditions. The study is carried out on two samples with initial purities of 38-57 wt % and ash contents of up to 16 wt %. Under the optimal process conditions, glycerol exhibits a remarkable increase to 85 wt % purity while preserving the overall glycerol recovery of the process of up to 71%. Among different purification steps, neutralization contributes to increasing the purity to 69 wt % while the remaining water and methanol evaporation have further increased the purity to >80 wt %. The adsorption step shows the smallest increase in glycerol purity despite it being required to decolorize and deodorize the final product. The developed process is further designed for industrial-scale application using Aspen Plus for a plant size of 1630 kg/h of purified glycerol which could achieve 82 wt % final purity and a maximum recovery of 77%. In addition, the process yields 315 kg/h of salable byproduct salts suitable as fertilizer and an overall CO emission of 0.70 ton per ton of purified glycerol mainly due to the unrecovered feedstock and solvent combustion. As a result, the proposed process implementation could generate positive revenues with a cost of the final products of €19.2 per ton.
本文展示了将废弃来源的粗甘油提纯至2000克规模，以提供一个综合的概念验证。从第二代生物柴油厂前所未有的低质量甘油开始，目前这些甘油按成本处理，实施了一系列物理化学步骤，以在相关条件下提高甘油纯度和回收率。该研究针对两个初始纯度为38 - 57 wt%且灰分含量高达16 wt%的样品进行。在最佳工艺条件下，甘油纯度显著提高至85 wt%，同时保持该工艺高达71%的总甘油回收率。在不同的提纯步骤中，中和作用使纯度提高到69 wt%，而剩余的水和甲醇蒸发进一步将纯度提高到>80 wt%。吸附步骤使甘油纯度提高幅度最小，尽管它是对最终产品进行脱色和除臭所必需的。所开发的工艺进一步设计用于工业规模应用，使用Aspen Plus对一个每小时生产1630千克提纯甘油的工厂进行模拟，该工厂可实现最终纯度82 wt%和最大回收率77%。此外，该工艺每小时可产出315千克可作为肥料销售的副产品盐，每吨提纯甘油的总一氧化碳排放量为0.70吨，这主要是由于未回收的原料和溶剂燃烧所致。因此，所提议的工艺实施可以产生正收益，最终产品成本为每吨19.2欧元。
