Microwave Augmented Reduction Using Hydrogen Enriched Methane

采掘冶金工业产生的温室气体排放量占总排放量的5%以上。由于对气候变化的日益关注，该行业在能源效率和环境管理方面正朝着更可持续的运营实践发展。微波处理是一项相对较新的技术，目前正在研究其在选矿和冶金提取中的应用。在过去的十年中，已经表明微波加热对于在火冶过程中加热感兴趣的材料，特别是金属氧化物具有许多潜在的优点。它可以提供体积，快速和选择性加热，并且电能可以相对清洁。此外，与化石燃料相比，废气、二氧化碳和灰尘的数量可以减少。因此，开发一种可以利用这些潜在的加热特性来提高能源效率的还原工艺是有利的。在短期内，将可再生能源与微波相结合，增强现有能源和更环保的还原剂可能是过渡解决方案的一部分。利用天然气（95%的甲烷）作为还原剂对环境的影响较小，而且可能非常活跃，这将是有利的。可再生能源可以用来产生微波和制造氢气来添加到甲烷中。处理这些环境问题的一种方法是研究替代能源和减少剂，以提高能源效率和减少碳足迹。因此，建议继续开展微波萃取金属的研究，重点关注甲烷作为金属氧化物还原剂的利用。这将涉及使用以下甲烷基还原剂的三管齐下的方法：(1)基本上是纯甲烷或天然气，(2)富氢甲烷或天然气（HENG）和(3)甲烷分解产生的活性碳/吸附碳。由于磁控管中电到微波的转换过程中的能量损失，单独的微波加热是相对低效的。提出将微波与传统热源相结合，在微波增强加热过程中提高整体效率。此外，微波可以催化甲烷的分解。因此，本研究的总体目标是将相对较新的微波加热技术与甲烷作为还原剂的未充分利用的潜力结合起来，特别是以非常活跃的形式产生碳。这种安排可以提高能源效率，大大减少温室气体排放，减少火法冶金过程对环境的影响。这对行业和社会都有好处。

The extractive metallurgy industry generates over five percent of the total greenhouse gas emissions. As a result of the increasing concern for climate change, this industry is moving towards more sustainable operating practices with regards to energy efficiency and environmental stewardship. Microwave processing is a relatively new technique, which is being studied for application in mineral processing and metallurgical extraction. In the last decade, it has been shown that microwave heating has a number of potential advantages for heating materials of interest in pyrometallurgical processes, in particular metal oxides. It can provide volumetric, rapid and selective heating and also the electrical energy source can be relatively clean. Additionally in comparison to fossil fuels, the amounts of off--gases, carbon dioxide and dust can be reduced. Thus, it would be advantageous to develop a reduction process which can utilize these potential heating characteristics for improved energy efficiency. In the short term, the combination of renewable energy resources with a microwave augmented existing energy source and a more environmentally friendly reductant may be part of a transitional solution. The utilization of natural gas (95% methane) as a reducing agent, which has less of an environmental impact and can also be potentially very reactive, would be advantageous. Renewable energy sources can be utilized to produce the microwaves and to manufacture hydrogen to add to methane.  One approach to deal with these environmental issues is to investigate alternative energy sources and reducing agents in order to improve the energy efficiency and to reduce the carbon footprint. In this regard, it is proposed to continue research on the utilization of microwaves for metal extraction and focus on the utilization of methane as a reducing agent for metal oxides. This will involve a three-pronged methodology using the following methane-based reducing agents: (1) essentially pure methane or natural gas, (2) hydrogen-enriched methane or natural gas (HENG) and (3) reactive carbon/adsorbed carbon produced from the decomposition of methane. Microwave heating alone is relatively inefficient due to the energy losses during the conversion of electricity to microwaves in the magnetron. It is proposed to combine microwaves with a conventional heating source, in a microwave augmented heating process with an overall improved efficiency. Also, microwaves may catalyze the decomposition of methane. Thus, the overall objective of this research is to combine the relatively new microwave heating technology together with the somewhat underutilized potential of methane as a reducing agent and in particular produce carbon in a very reactive form. This arrangement could lead to improved energy efficiencies, significantly reduced greenhouse gas emissions and reduced impact of pyrometallurgical processes on the environment. This would of benefit to both the industry and society.