Torrefied versus conventional pellet production – A comparative study on energy and emission balance based on pilot-plant data and EU sustainability criteria
Torrefied versus conventional pellet production – A comparative study on energy and emission balance based on pilot-plant data and EU sustainability criteria
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DOI：
10.1016/j.apenergy.2014.08.017
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发表时间：
2015-01
期刊：
影响因子：
11.2
通讯作者：
D. Agar;J. Gil;D. Sánchez;I. Echeverría;M. Wihersaari
中科院分区：
文献类型：
--
作者：
D. Agar;J. Gil;D. Sánchez;I. Echeverría;M. Wihersaari
烘焙是一种新兴技术，其能够实现生物质与煤的更大的共烧速率。然而，到目前为止，缺乏中试规模烘焙厂的真实的生产数据。没有这样的数据的任何环境效益的焙烧颗粒production.In这项研究中的消耗品投入的数据从半工业焙烧厂和生产的颗粒的物理性能被用来分析能源投入和空气排放的焙烧颗粒生产和产品运输是难以量化的。欧盟可持续性标准用于比较从采伐剩余物到最终使用与煤共烧的颗粒的焙烧和常规颗粒生产的CO2当量排放。一个生产场景中，原材料的供应和生产发生在芬兰与在西班牙共烧。分析了欧洲和北美代表性生产基地运输距离（卡车、铁路和船舶）对环境影响的影响，结果表明每吨焙烧球团消耗约4.5 GJ的能量，而传统球团消耗3.3 GJ，分别占球团能量含量的23%和21%。如果可以使用可再生能源的电力，化石燃料在输入能源中的比例可以分别降低到37%和41%。在共烧中生产和使用这两种颗粒类型具有类似的环境影响，产生的电力二氧化碳当量排放量在43-45 g MJ−1范围内。通过将焙烧颗粒与化石煤共烧，可以实现77%的减排。颗粒生产量对应于每千克原料产生4.3和4.2兆焦耳的电力（干质量）和共烧比如果仅使用一种产品运输模式，则发现当运输距离大于400 km（货车）时，焙烧球团生产和共烧产生的排放比其常规对应物少，1850公里（铁路）和25，500公里（船舶）。
Torrefaction is an emerging technology which enables greater co-firing rates of biomass with coal. To date however there has been a lack of real production data from pilot-scale torrefaction plants. Without such data any environmental benefits of torrefied pellet production are difficult to quantify.In this study data on consumable inputs from a semi-industrial torrefaction plant and the physical properties of produced pellets are used to analyse energy input and air emissions of torrefied pellet production and product transport. EU sustainability criteria are used to compare CO2-equivalent emissions from torrefied and conventional pellet production starting from harvesting of logging residues to end use of co-firing the pellets with coal. A production scenario is examined in which raw material supply and production takes place in Finland with co-firing in Spain. The influence of transport distance (by lorry, rail and ship) on environmental impact is analysed for European and representative North American production sites.Results indicate about 4.5 GJ of energy is consumed for each tonne of torrefied pellets compared to 3.3 GJ for conventional pellets; representing 23% and 21% of the energy content of the pellets respectively. If electricity from renewable sources can be used, the fossil fuel fraction of input energy can be reduced to 37% and 41% respectively. Production and use of both pellet types in co-firing have similar environmental impact generating CO2-equivalent emissions from electricity in the range 43–45 g MJ−1. An emission savings of 77% can be realised by co-firing torrefied pellets with fossil coal. Pellet production amounts correspond to 4.3 and 4.2 MJ generated electricity for each kilogram of feedstock (dry mass) and co-firing ratios (energy basis) in the range of 1.4–1.8%.If only one mode of product transport is used torrefied pellet production and co-firing is found to generate fewer emissions than its conventional counterpart when transport distance is more than 400 km (lorry), 1850 km (rail) and 25,500 km (ship).