SBIR Phase I: Closed Loop Solvent Evaporation Ovens

这个小型企业创新研究（SBIR）第一阶段项目将开发闭环溶剂蒸发炉。 目前，工业过程使大量的热空气通过蒸发炉，产生被挥发性有机碳（VOC）化合物污染的空气流流出物。 这些存在环境问题并且没有回收溶剂的机会。 所提出的工艺是一个封闭的闭环系统，使用氮气作为再循环气体和膜来回收蒸发的溶剂蒸气并除去从空气中泄漏到气体中的氧气和水蒸气。 所需的补充氮气量很小。 通过避免处理稀释VOC污染气流的成本和回收溶剂的价值，运营成本是合理的。 第一阶段的主要实验任务包括选择一个氧气可渗透的，溶剂蒸气/氮气不可渗透的膜的氧气去除步骤。 膜必须在高溶剂蒸气压和高进料气体温度下保持这些性质。 还将设计该系统的原型，并估计建造费用。 第二阶段将建立一个完整的系统，并在实验室和合作的主机站点运行，以评估过程的效益和成本。用经济实惠的闭环氮气再循环系统取代直接通风的溶剂蒸发炉将成为可行的，用于片剂包衣和印刷操作，制备胶带和粘合膜，以及工业中常见的表面包衣，上光和喷漆操作。 新的烘箱系统将允许溶剂回收和再利用，消除麻烦的蒸汽排放a，并提供许多加工优势。 基于该技术的经济实惠的系统预计将得到广泛使用。

This Small Business Innovation Research (SBIR) Phase I project will develop closed-loop solvent evaporation ovens. Currently, industrial processes pass large.volumes of heated air through the evaporation oven, producing an air stream effluent contaminated by volatile organic carbon (VOC) compounds. These present environmental problems and no opportunity for recovery of the solvent. The proposed process is an enclosed, closed-loop system using nitrogen as the recirculating gas and a membrane to recover the evaporated solvent vapors and remove oxygen and water vapor derived from air that leaks into the gas. The amount of make-up nitrogen required will be small. Operating costs would be justified by the avoided costs of treating the dilute VOC-contaminated air stream and by the value of the recovered solvent. The main Phase I experimental task involves a selection of an oxygen-permeable, solvent vapor/nitrogen-impermeable membrane for the oxygen removal step. The membrane must retain these properties at high solvent vapor pressures and high feed gas temperatures. A prototype of the system will also be designed and the construction costs estimated. Phase II will build a complete system and operate it in the laboratory and at cooperating host sites to evaluate process benefits and costs.Replacement of direct-air-vented solvent evaporation ovens with affordable closed-loop nitrogen recirculation systems would become feasible for use in tablet coating and printing operations, preparation of tapes and adhesive films, and surface coating, varnishing, and painting operations common in industry. The new oven systems will allow solvent recovery and reuse, eliminate troublesome vapor emissiona, and offer many processing advantages. Affordable systems based on this technology are expected to be widely used.