国际生物炭协会IBI :生物炭常见问题解答 FREQUENTLY ASKED QUESTIONS ABOUT BIOCHAR
发布日期：2016-8-28 9:23:09 浏览量：
生物炭是指生物质在缺氧或低氧环境下经过热化学转化后的固体产物。在其他技术术语中，生物炭是指由有机材料（如木材、粪肥或叶子等生物质）在有限的氧气（O2））供应以及相对较低的温度（<700℃）条件下热裂解后的产物。这个过程类似于木炭生产，这也许是人类发展最古老的工业技术。生物炭与一般木炭不同—-主要用作燃料—-其中一个主要应用是作为土壤改良剂，改善土壤条件以及减少温室气体排放量。Biochar is a solid material obtained from the carbonization thermochemical conversion of biomass in an oxygen-limited environments. In more technical terms, biochar is produced by thermal decomposition of organic material (biomass such as wood, manure or leaves) under limited supply of oxygen (O2), and at relatively low temperatures (<700°C). This process mirrors the production of charcoal, which is perhaps the most ancient industrial technology developed by humankind. Biochar can be distinguished from charcoal—used mainly as a fuel—in that a primary application is use as a soil amendment with the intention to improve soil functions and to reduce emissions from biomass that would otherwise naturally degrade to greenhouse gases.
Sustainable biochar is a powerfully simple tool that can 1) fight global warming; 2) produce a soil enhancer that holds carbon and makes soil more fertile; 3) reduce agricultural waste; and 4) produce clean, renewable energy. In some biochar systems all four objectives can be met, while in others a combination of two or more objectives will be obtained.碳化是指通过还原热处理将原料转化成生物炭的过程。其中受到时间、热量和压力等因素影响，而这些因素会因不同设备以及原料有差异。有两个主要过程：热解或气化。在生产生物炭的过程中，也会产生气体或油状的能源产品。这些能源产品可用于其它用途，或者可以简单燃烧，释放热量。此外，生产生物炭可以利用各种各样的生物质原料。Carbonization is the process of converting a feedstock into biochar through reductive thermal processing. The process involves a combination of time, heat and pressure exposure factors that can vary between processors, equipment, and feedstocks. There are two main processes: pyrolysis or gasification. Energy products in the form of gas or oil are produced along with the biochar. These energy products may be recoverable for another use, or may simply be burned and released as heat. In addition, biochar can be made from a wide variety of biomass feedstocks.How do we know that biochar helps increase crop yields?目前有大量文献资料量化描述了生物炭有利于提高农作物产量。过去几年里，在热带地区对生物炭进行了田间试验。大多数据显示生物炭应用到土壤中，对土壤养分都产生了积极的影响。
There is a large body of peer-reviewed literature quantifying and describing the crop yield benefits of biochar-amended soil. Field trials using biochar have been conducted in the tropics over the past several years. Most show positive results on yields when biochar was applied to field soils and nutrients were managed appropriately.在土壤中使用木炭已有上千年历史。最知名的例子是巴西肥沃的“黑土”(Terra Preta)，日本也有在土壤中使用木炭。巴西和日本的传统都显示了生物炭对土壤有积极影响。There is also evidence from thousands of years of traditional use of charcoal in soils. The most well-known example is the fertile Terra Preta soils in Brazil, but Japan also has a long tradition of using charcoal in soil, a tradition that is being revived and has been exported over the past 20 years to countries such as Costa Rica. The Brazilian and Japanese traditions together provide long-term evidence of positive biochar impact on soils.虽然生物炭对土壤和气候的影响是肯定的，但是一些生物炭的生产也值得探讨。目前正在努力多样化地在土壤中利用生物炭，实现生物炭价值最大化。While the larger questions concerning overall biochar benefits to soils and climate have been answered in the affirmative, significant questions remain, including the need for a better understanding of some of the details of biochar production and characterization. Work is ongoing to develop methods for matching different types of biochar to soils for the best results.How can biochar help farmers?使用生物炭可以改善土壤肥力。单独使用，或以一定比例与肥料等农用化学品组合添加到土壤中。当时，这些营养物质与生物炭组合使用时，可以减少其施用率。生物炭保存在土壤中，可以带来多年的好处。当将有机残留物转化成生物炭时，通过捕获在生物炭生产过程中释放出的能量，农民也可以得到能量产量。在工业化国家和发展中国家，土壤流失和退化在以前所未有的速度出现，对土壤生态系统性能产生深远的影响。在许多地区，土壤生产力的损失出现，尽管集约利用农药，对土水资源产生不利影响。生物炭在扩大土壤可持续管理上发挥重要作用，可以通过改进现有的最佳管理实践，不但提高土壤生产力还可以减少养分流失。Biochar provides a unique opportunity to improve soil fertility for the long term using locally available materials. Used alone, or in combinations, compost, manure and/or agrochemicals are added at certain rates every year to soils, in order to realize benefits. Application rates of these can be reduced when nutrients are combined with biochar. Biochar remains in the soil, and single applications can provide benefits over many years. Farmers can also receive an energy yield when converting organic residues into biochar by capturing energy given off in the biochar production process. In both industrialized and developing countries, soil loss and degradation is occurring at unprecedented rates, with profound consequences for soil ecosystem properties. In many regions, loss in soil productivity occurs despite intensive use of agrochemicals, concurrent with adverse environmental impacts on soil and water resources. Biochar can play a major role in expanding options for sustainable soil management by improving upon existing best management practices, not only to improve soil productivity but also to decrease nutrient loss through leaching by percolating water. Can you add biochar to alkaline soils?大多数生物炭试验都是在酸性土壤中进行，使用较高的pH值（例如6-10）生物炭。一项分别将生物炭加入酸性和碱性土壤的对比研究发现，在酸性土壤中加入更有益农作物生长，而在碱性土壤中加入效果不明显。在另一项研究中，土壤中添加生物炭引起pH升高，当pH值大于6时，由于微量元素出现不足，对产量有不利的影响。所以往碱性土壤中加入任何有石灰含量的物质时，必须要谨慎。不过也有可能生产出适用于碱性土壤的生物炭。Most biochar trials have been done on acidic soils, where biochars with a high pH (e.g. 6-10) were used. One study that compared the effect of adding biochar to an acidic and an alkaline soil found greater benefits on crop growth in the acidic soil, while benefits on the alkaline soil were minor. In another study, adding biochar to soil caused increases in pH which had a detrimental effect on yields, because of micronutrient deficiencies which occur at high pH (>6). Care must be taken when adding any material with a liming capacity to alkaline soils; however, it is possible to produce biochar that has little or no liming capacity that is suitable for alkaline soils.How long does biochar persist in the soil?生物炭的特性取决于不同的原料以及生产方式。 生物炭一个统一特性，它在土壤中矿化的速度比其未碳化材料（原料）慢得多。大多数生物炭确实有一个小部分不稳定（易分解）的碳，但通常更大部分是顽固的（稳定）。科学家已经证明，这种稳定部分平均停留时间（即生物炭将在土壤中持续的时间估计）从几十年到几千年不等。
Biochar is a spectrum of materials, and its characteristics vary depending upon what it is made from and how it is made. One unifying characteristic of biochars, however, is that it mineralizes in soils much more slowly than its uncharred precursor material (feedstock). Most biochars do have a small labile (easily decomposed) fraction of carbon but there is typically a much larger recalcitrant (stable) fraction. Scientists have shown that the mean residence time (the estimated amount of time that biochar carbon will persist in soils) of this recalcitrant fraction ranges from decades to millennia.Why is biochar persistence in soils important?生物炭并入土壤中的持久性之所以至关重要原因是生物炭的环境效益：首先，它决定了在生物炭的碳元素封存在土壤中和对气候变化的减缓的持续时间；其次，它决定了生物炭对土壤和水的质量效益的持续时间。The persistence of biochar when incorporated into soils is of fundamental importance in determining the environmental benefits of biochar for two reasons: first, it determines how long carbon in biochar will remain sequestered in soil and contribute to the mitigation of climate change; and second, it determines how long biochar can provide benefits to soil and water quality.How can biochar mitigate climate change?当前大量农林业废弃物和其他生物质都是烧毁或置之不理，这些都会分解从而释放二氧化碳（CO2）和甲烷（CH4）- 大气中两个主要的温室气体（GHGs）。当在全球范围内通过将亿吨生物质转化为生物炭，有研究表明，生物炭有潜力可以降低大气中的温室气体浓度，以减缓全球气候变化（Woolf等人, 2010）。Large amounts of forestry and agricultural residues and other biomass are currently burned or left to decompose thereby releasing carbon dioxide (CO2) and/or methane (CH4)—two main greenhouse gases (GHGs)—into the atmosphere. Under biochar conversion scenarios, easily mineralized carbon compounds in biomass are converted into fused carbon ring structures in biochar and placed in soils where they persist for hundreds or thousands of years. When deployed on a global scale through the conversion of gigatonnes of biomass into biochar, studies have shown that biochar has the potential to mitigate global climate change by drawing down atmospheric GHG concentrations (Woolf et al, 2010).Does a successful biochar industry depend on carbon markets?生物炭可为农民带来直接的效益，以及许多其他可量化的环境效益，其中包括减缓气候变化。尽管正在努力建立机制，以量化和货币化生物炭对环境的积极效应——主要以碳抵消的形式——这只会增加对农民和其他利益相关者现有的财政奖励。
Biochar offers direct, present day benefits to farmers of all sizes in the form of greater crop productivity as well as numerous other quantifiable environmental benefits, among them climate change mitigation. While efforts are underway to develop mechanisms to quantify and monetize the climate benefits of biochar—chiefly in the form of carbon offset methodologies—these would only add to the existing financial incentives for farmers and other stakeholders to adopt biochar.Is biochar production sustainable?生物炭的生产和使用包括一个复杂的系统，它的可持续性涉及各种组件。在支持生物炭行业商业化发展的所有关键因素中，原料供应和可持续产量问题是目前最重要的，无论是从可持续发展还是金融和商业角度上看。这将要求用于生物炭生产的生物质来源的适当性，并能够承受整个生命周期分析。生物炭生产应该利用废物。当前大量的农业、市政和林业生物质烧毁或分解释放出二氧化碳和甲烷到大气中。这些包括农作物残余物（如坚果壳、果核等），食品、林业废弃物和动物粪便。用这些材料制作生物炭将意味着与其他土地用途没有竞争。
Biochar production and use comprises a complex system and its sustainability must be parsed out into various components. Of all the key factors that will support the fastest commercialization of the biochar industry, feedstock supply and sustainable yield issues are by far the most important, from both a broad sustainability perspective and from the financial and commercial points of view. This will require the sources of biomass selected for biochar production to be appropriate and be able to withstand a comprehensive life cycle analysis. Biochar can and should be made from waste materials. Large amounts of agricultural, municipal and forestry biomass are currently burned or left to decompose and release CO2 and methane back into the atmosphere. These include crop residues (both field residues and processing residues such as nut shells, fruit pits, etc), as well as yard, food and forestry wastes, and animal manures. Making biochar from these materials will entail no competition for land with any other land use option.生物炭是改善土壤和土壤固碳的工具。但是这项技术必须通过尊重原住民的土地权利和支持健康自然生态系统的方式来实现。Biochar can be a tool for improving soils and sequestering carbon in soil. However, this technology as any other must be implemented in a way that respects the land rights of indigenous people and supports the health of natural ecosystems.What are the costs and benefits of producing and using biochar?生产和使用生物炭带来的好处包括，减少废物，能源合作生产，提高土壤肥力和结构，减缓气候变化。并非所有的这些好处都被计入当前的经济体制下，但未来在碳约束的经济下，减缓气候变化效益可能被纳入为经济效益。生物炭的部分效益被生产成本抵消了，主要涉及原料运输和加工。生物炭系统的盈利能力将受能源价格和减少温室气体排放影响。The benefits that potentially flow from biochar production and use include waste reduction, energy co-production, improved soil fertility and structure, and climate change mitigation. Not all of these benefits are accounted for under current economic systems, but under the carbon constrained economies of the future, the climate mitigation benefit is likely to be accounted for as an economic benefit. Biochar benefits are partly offset by the costs of production, mainly hauling and processing feedstocks. Profitability of biochar systems will be especially sensitive to prices for energy and for greenhouse gas reductions and offsets.
来源：国际生物炭协会International Biochar Initiative