1.1 本指南涵盖并提供了报废轮胎的材料回收指南，以确定其燃料价值。将整个废轮胎转化为用作燃料的碎屑，生产出一种称为轮胎衍生燃料（TDF）的产品。本《恢复指南》已从20世纪80年代初的一个开创性概念转变为在美国工业和公用事业应用中得到验证和持续使用。 1.2 在美国，设计用于使用固体燃料（如煤或木材，或两者）的燃烧装置相当多。其中许多装置现在使用TDF，尽管它们不是专门设计用于燃烧TDF的。很明显，TDF的燃烧特性与其他碳基固体燃料相似。相似之处导致了对现有燃烧装置的实用测试。成功的测试使TDF在现有燃烧装置中与传统燃料混合时，随后被接受为补充燃料。 需要修改适当的现有燃烧装置，以适应TDF范围从无到相对较小的变化。正确的应用和规范问题对于成功利用这种替代能源至关重要。 1.3 本指南解释了TDF在正常操作条件下与原始指定燃料混合和燃烧时的使用。本文不讨论用于能量回收的整个轮胎燃烧，因为整个轮胎的使用不需要按照规定的燃料规格对轮胎进行处理。 1.4 以英寸-磅为单位的数值应视为标准值。括号中给出的值是到国际单位制的数学转换，仅供参考，不被视为标准值。 1.5 本标准并非旨在解决与其使用相关的所有安全问题（如有）。 本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.6 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 在考虑锅炉燃料规范时，需要评估的问题是燃料的燃烧特性、搬运和进料物流、环境问题和灰渣考虑。为了设计发电和蒸汽发电的燃烧装置，需要彻底了解这些问题； 然而，TDF已经证明了兼容的特性，使其能够作为现有燃烧装置的补充燃料，这是基于许多最初为传统化石燃料或木材废物设计的设施的累积经验。当在现有装置中用作补充能源时，TDF的使用通常限于基于能量输入的10%至30%范围内的混合比。这一限制是由于其高放热率和低水分含量，与其他固体燃料（如木材、垃圾衍生燃料、煤炭和石油焦）显著不同。 4.2 专用于使用TDF（或整个轮胎）作为唯一燃料源的新型燃烧装置很少。报废轮胎的产生和可用性最终取决于新轮胎的市场条件和报废轮胎库存（库存）的消耗率。 废轮胎约占城市固体废物流的1%。根据全国废轮胎的产生率，大约有250万至300万吨（每年可用于所有用途，包括燃料、橡胶屑、工程项目等）。一些专用燃烧装置已经建成，然而，随着其他现有来源开始使用TDF，对废轮胎的竞争将决定这些设施的最终可行性。虽然大多数地区可以提供TDF需求作为补充燃料，但专用锅炉的容量范围为500 000磅/小时（227 000 kg/h）蒸汽容量需要超过66 000个废轮胎/天，以满足其燃料需求。这种需求可能会使一个地区的供应能力紧张，并使燃料供应面临风险。一些设计项目将TDF作为补充燃料，与木材、煤炭、焦炭、污泥或多种燃料的某些组合一起使用，其中需求与供应可用性一致。 4.3 了解TDF选择作为现有发电机组补充燃料的目标很重要。几个模型目标可能如下: 4.3.1 在使用木材、污泥和煤的联合燃烧锅炉中提高锅炉效率； 4.3.2 采购价格具有竞争力的燃料； 4.3.3 补充现有燃料的有限供应； 4.3.4 使用优质燃料； 4.3.5 通过使用与某些煤或石油焦相比硫含量相对较低的燃料来实现环境效益，以及； 4.3.6 提供公共和社会效益，解决区域固体废物问题。 4.4 锅炉通常围绕在动力装置整个摊销寿命内可用的燃料进行设计。这里的锅炉设计讨论有限，因为已经制定了TDF标准尺寸规范，以确保TDF在现有系统中的性能。 TDF作为一个整体从固体废物流中开采，然后通过加工技术进行设计，以适应新的或现有的燃烧装置。对燃烧装置进行重大修改或重新设计以适应TDF通常会使其作为补充燃料的使用不经济。TDF的使用在经济上取决于以下两个问题: 4.4.1 燃烧装置在不进行修改的情况下使用燃料的现有能力（除氧气炉排速度调整和进料/物料处理的微小操作变化外），以及， 4.4.2 供应商经济地收集、处理TDF并将其运输至燃烧装置的能力。 4.5 一旦做出经济决策，将TDF开发为特定机组的燃料源，就必须正确评估燃料规格问题，包括尺寸、近似分析和最终分析、燃烧特性和环境问题，以确定TDF是否是适当的补充燃料资源，而无需对系统进行重大修改。 图1 燃料的相对能量比较（单位:Btu/t）

1.1 This guide covers and provides guidance for the material recovery of scrap tires for their fuel value. The conversion of a whole scrap tire into a chipped formed for use as a fuel produces a product called tire-derived fuel (TDF). This recovery guide has moved from a pioneering concept in the early 1980s to a proven and continuous use in the United States with industrial and utility applications. 1.2 Combustion units engineered to use solid fuels, such as coal or wood, or both, are fairly numerous throughout the U.S. Many of these units are now using TDF even though they were not specifically designed to burn TDF. It is clear that TDF has combustion characteristics similar to other carbon-based solid fuels. Similarities led to pragmatic testing in existing combustion units. Successful testing led to subsequent acceptance of TDF as a supplemental fuel when blended with conventional fuels in existing combustion devices. Changes required to modify appropriate existing combustion units to accommodate TDF range from none to relatively minor. The issues of proper applications and specifications are critical to successful utilization of this alternative energy resource. 1.3 This guide explains TDF’s use when blended and combusted under normal operating conditions with originally specified fuels. Whole-tire combustion for energy recovery is not discussed herein, since whole-tire usage does not require tire processing to a defined fuel specification. 1.4 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 4.1 When considering the specification of fuels for a boiler, issues to evaluate are the fuel’s combustion characteristics, handling and feeding logistics, environmental concerns, and ash residue considerations. A thorough understanding of these issues is required to engineer the combustion unit for power and steam generation; however, TDF has demonstrated compatible characteristics allowing it to serve as a supplemental fuel in existing combustion units based on cumulative experience in many facilities originally designed for traditional fossil fuels, or wood wastes, or both. When used as a supplemental energy resource in existing units, TDF usage is generally limited to blend ratios in the 10 to 30 % range based on energy input. This limit is due to its high heat release rate and low moisture content, which differ significantly from other solid fuels such as wood, refuse-derived fuel, coal, and petroleum coke. 4.2 New combustion units dedicated to the use of TDF (or whole tires) as the sole fuel source are rare. The generation and availability of scrap tires are ultimately determined by market conditions for new tires and the depletion rate of scrap tire inventories (stockpiles). Scrap tires account for approximately 1 % of the municipal solid waste stream. Based on a national scrap tire generation rate, there are roughly 2.5 to 3 million tons (annually available for all uses to include fuel, crumb rubber, engineering projects, and so forth). Some dedicated combustion units have been built, however, competition for the scrap tires as other existing sources begin to use TDF will determine the ultimate viability of these facilities. Although most regions can supply TDF demand as a supplemental fuel, a dedicated boiler in the range of 500 000 lb/h (227 000 kg/h) steaming capacity would require over 66 000 scrap tires/day to meet its fuel demand. Such demand may strain a region's ability to supply and put the fuel supply at risk. Some design projects have incorporated TDF as a supplemental fuel with wood, coal, coke, sludge, or some combination of multiple fuels where demand is consistent with supply availability. 4.3 It is important to understand what objectives may lead to TDF’s choice as a supplemental fuel in existing power units. Several model objectives may be as follows: 4.3.1 To increase boiler efficiency in a co-fired boiler using wood, sludge, and coal; 4.3.2 To procure a competitively priced fuel; 4.3.3 To supplement limited supplies of an existing fuel; 4.3.4 To use a high-quality fuel; 4.3.5 To achieve environmental benefits by using a fuel with a relatively low sulfur content in comparison to certain coals or petroleum coke, and; 4.3.6 To provide a public and social benefit that solves a regional solid waste problem. 4.4 Boilers generally are engineered around fuels that will be available through the amortized life of the power unit. Boiler design discussions here are limited as TDF standard size specifications have been developed to ensure TDF’s performance in existing systems. TDF is mined from the solid waste stream as a whole tire, then engineered via processing techniques to fit a new or existing combustion unit. A major modification or re-engineering of the combustion unit to accommodate TDF normally would make its use uneconomical as a supplemental fuel. TDF's use is economically dependent on the following two issues: 4.4.1 A combustion unit’s existing ability to use the fuel without modification (other than minor operational changes in oxygen grate speed adjustments, and feed/material handling) and, 4.4.2 The ability of a supplier to economically collect, process, and transport TDF to the combustion unit. 4.5 Once an economic decision has been made to develop TDF as a fuel source for a particular unit, issues of fuel specifications including size, proximate and ultimate analysis, combustion characteristics, and environmental concerns must be evaluated properly to determine whether TDF is an appropriate supplemental fuel resource without major system modification. FIG. 1 Relative Energy Comparison of Fuels (Scale in Btu/ton)