SBIR Phase I: Terahertz hydration monitoring for paper manufacturing

这个小型企业创新研究计划（SBIR）第一阶段项目将专注于设计、建造和验证用于造纸的太赫兹（THz）水合绘图系统。太赫兹辐射被定义为电磁波谱的亚毫米区域，是一个相对较新的、不断扩大的研究领域，有望具有独特的成像能力。太赫兹成像利用100 GHz至10太赫兹波段的照明，在近红外、可见光和紫外波段操作的系统无法实现的目标中产生对比度。太赫兹照明非常适合于无损评估、安全成像、过程控制和医学成像，原因有很多，包括其非电离性质、波长、可实现的宽瞬时带宽，以及太赫兹频率下水的介电常数的实数和虚数部分很大。造纸行业目前缺乏具有足够空间分辨率和水浓度灵敏度的水化计量方法来检测干燥纸制品中水分的局部分布，而且目前的行业标准成本高昂，并且由于其相关的电离辐射而存在安全问题。该项目的广泛影响/商业潜力跨越了几个依赖谨慎湿度控制的领域，包括木材制造、塑料、农业、化学加工和混凝土制造。该提案将首先关注造纸过程，这是一个非常昂贵的资本密集型过程。纸机的停机时间和废纸（不需要的纸）都是非常宝贵的。因此，过程控制是关键，快速和一致地去除水的能力是最重要的过程控制变量之一。不合规格的水分增加了停机时间，降低了效率，增加了成本，增加了废料水平，并降低了消费者的质量。目前的工艺控制技术不足，导致成本增加，能源使用增加，大量废纸必须回收或填埋。全球造纸行业规模巨大，仅在美国，每年的销售额就超过1300亿美元，产品产量接近1亿吨。因此，过程控制方面的改进可以显著降低全球能源使用、全球木材消耗和纸张成本。

This Small Business Innovation Research Program (SBIR) Phase I project will focus on the design, construction, and verification of a terahertz (THz) hydration mapping system for use in paper manufacturing. THz radiation is defined as the submillimeter region of the electromagnetic spectrum, and is a relatively new and expanding area of research that promises unique imaging capabilities. THz imaging utilizes illumination from the 100 GHz to 10 THz band to generate contrast in targets unavailable to systems operating in the NIR, visible, and UV bands. THz illumination is ideally suited to nondestructive evaluation, security imaging, process control, and medical imaging for a number of reasons, including its nonionizing nature, its wavelength, its achievable broad instantaneous bandwidth, and the large real and imaginary parts of the dielectric constant of water at THz frequencies. Paper manufacturing currently lacks hydration metrology with sufficient spatial resolution and water concentration sensitivity to detect local distributions of water in drying paper products, and the current industry standard is costly and has safety concerns due to its associated ionizing radiation. The broader impact/commercial potential of this project spans several fields that rely on careful moisture control, including wood manufacturing, plastics, agriculture, chemical processing, and concrete manufacturing. This proposal will initially focus on the papermaking process, which is a very expensive, capital-intensive process. Both downtime on a paper machine and scrap paper (unwanted paper) are highly valuable. As a result, process control is key, and the ability to remove water quickly and consistently is one of the most important process control variables. Out-of-spec moisture increases downtime, reduces efficiency, increases costs, increases scrap levels, and reduces quality to the consumer. Current process control techniques are insufficient and lead to added cost, increased energy use, and a large amount of wasted paper that must be recycled or land filled. The global paper manufacturing industry is enormous, with over $130 billion in sales and nearly 100 million metric tons of product annually in the U.S. alone. Therefore, improvements in process control can result in significant reductions in global energy use, global wood consumption, and paper costs.