Year: 2017
Type: dissertation
Abstract: Microcrystalline cellulose (MCC) is a cellulose-based, powder-like product invented in the 1950s. Today, it is mostly used in medical and food industry applications. The first processing plant with the annual capacity of 6,800 tonnes was built in 1962 in the United States, in the city of Newark, Delaware. Currently, 120,000 tonnes of MCC is produced globally each year, a relatively small number in comparison with chemical pulps, whose production totals around 135,820,000 tonnes. Most of the studies on MCC are focused on the final product itself rather than the production method. This study provides comprehensive scientific examination of the new production method for MCC, including its technological, economic and environmental aspects. The aim was to find a solution for the industrial scale manufacture of MCC while having low production costs that enable significant increase in product capacity and reducing the price of the final product, at the same time discovering new use targets and applications. Carrying out the integration of the process of manufacturing MCC in a chemical pulp mill was the starting point for this work. The raw material used in the laboratory tests was sulphate-based softwood pulp, including both bleached and unbleached variety. Test conditions were selected to enable upscaling the process to a pulp mill. In addition, a new MCC product (MCC with lignin concentration) was developed and the suitability of MCC as raw material for microfibrillated cellulose (MFC) was tested in this study. The results indicate that MCC can be manufactured in conditions that can be realised in an industrial scale process integrated in a pulp mill. Changing the reaction conditions allows manufacturing different qualities of product and by using unbleached chemical pulp as raw material enables to produce totally new products, MCC with lignin concentration. MCC was found to be a suitable raw material in the manufacture of MFC. The results also indicated that the implementation of a stand-alone type plant unit and a MCC plant integrated in a pulp mill is technically possible and also profitable. However, when integrated into a pulp mill, the MCC process was found to be even more profitable, as the mill provides an energy self-sufficient platform that already includes certain equipment, thus reducing investment costs. When examining the new production method from an environmental perspective, it was pointed out that the burden caused by the new method is less severe to the environment than the currently existing methods when using the GWP (global warming potential) as the impact class. Other impact classes were not examined in detail. As a continuation of this study, further research should focus on testing industrial scale process equipment and developing new final product applications requiring large capacity.
Source: Aaltodoc (Aalto University)
Author: Vanhatalo, Kari
Language: English
Subfield: Biomaterials
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7020900658