Integration of bio-carbon in the formulation of carbon electrodes for metallurgical processes- Al smelting process

本研究项目旨在开发一种以生物炭替代石油焦的工艺，用于冶金操作中碳电极的生产，特别是铝电解阳极的制造。一个多世纪前，铝工业在加拿大实施，今天是加拿大的主要产业之一，每年生产300万吨原金属，确保超过10000个直接和20000个间接就业岗位，每年为该国经济贡献超过30亿美元。铝的传统生产方法是hall - h<s:1>法，包括电解溶解在熔融冰晶石中的氧化铝。虽然这项技术现在已经有一百多年的历史了，铝的总产量在过去的50年里增长了100多倍，但工艺并没有发生实质性的变化，碳质材料仍然是阳极和阴极的主要成分。阳极主要由阳极级石油焦制成，在电解过程中消耗。全球铝产量的惊人增长和阳极级焦炭的短缺，促使该行业寻求替代碳源。乍一看，生物质基碳似乎是这个问题的自然解决方案，但是它不符合阳极所需的非常严格的规格。在这个研究项目中，我们打算探索在阳极配方中使用生物炭的可能性，并开发一种合适的工艺，以使生物炭符合行业规范，并最终用作阳极成分。

This research program aims at developing a process for substituting biochar for petroleum coke in production of carbon electrodes in metallurgical operations, especially in manufacturing of anodes for aluminum electrolysis. Implemented in Canada more than a century ago, aluminum industry today is one of the major Canadian industries, producing 3 Mt/y of primary metal, securing more than 10000 direct and 20000 indirect jobs, and contributing more than 3 B$/y to the economy of the country. Aluminum is conventionally produced by the Hall-Héroult process, involving the electrolysis of alumina, dissolved in molten cryolite. Although the technology is now more than one hundred years old and total aluminum production has grown more than one hundred times within the past fifty years, the process has not changed substantially and carbonaceous materials are still the main ingredients of both anode and cathode. Anode is essentially made of anode grade petroleum coke, and is consumed during the electrolysis process. The spectacular increase of global aluminum production and the shortage of anode grade coke push the industry for seeking alternative carbon sources. At a first glance, biomass-based carbon seems to be a natural solution for this issue, however it does not meet the very strict specifications required for anode. In this research program we intend to explore the possibility of using biochar in anode recipe and to develop an appropriate process in order that biochar meet the industry specifications and eventually be used as an anode ingredient.