Development of a High Performance Bioprocess for Eliminating 1,4-Dioxane in Water

描述(由申请人提供)：在美国各地，供水供应商和管理人员发现水中1，4-二恶烷的含量达到危险水平。这种化合物几十年来在广泛的应用中被使用，包括作为(1)油漆、清漆和印花中的溶剂；(2)人造皮革中的处理剂；(3)杀虫剂和熏蒸剂的成分；(4) 医药中的净化剂；(5)树脂、油、塑料、粘合剂、蜡和水泥中的溶剂。1，4-二恶烷在水中的含量极低(十亿分之一)，可能是一种人类致癌物质。它是高度溶解的，因此在地下水系统中广泛传播。最重要的是，没有传统的水处理技术可以从水中去除1，4-二恶烷。去除水中1，4-二恶烷的途径只有两种：紫外光或过氧化氢结合臭氧氧化(即高级氧化)和生物降解。紫外线和化学氧化过程的能源和化学成本往往高得令人望而却步。生物降解还存在产生有害副产品(如致癌的溴酸盐)的巨大风险，这些技术在某些情况下的适用性有限。生物降解还存在一些缺点，包括工艺稳定性、需要诱导降解、性能有限、堵塞、性能敏感性以及产生污泥或二次废流。然而，如果这些问题能够克服，生物处理提供了一种很有前途的方法，可以完全将1，4-二恶烷降解成无害的产品，并确保环境的完整性。这项拟议的研究建立在两项新发现的基础上。首先，已经发现了一种显然不需要预先诱导的高速率生物治疗途径。这一发现可能会大大简化治疗过程。其次，这一途径可以用于一种新的高性能生物过程，该过程可能会克服传统生物治疗所面临的大部分或全部工程障碍。具体地说，拟议的研究建立在这些初步成功的基础上，并通过单独使用1，4-二氧六环和在存在共同污染物三氯乙烯(TCE)的情况下进行一系列实验室(动力学)经验来证明这些初步成功。然后设计并建造了连续流生物反应器样机。该模型在几个月的时间里进行了广泛的测试，使用了污染现场的实际地下水，以确定其在一系列操作条件下的具体表现。这些性能参数被用来设计一个更大的中试规模的反应堆，该反应堆将在下一阶段的研究中在现场进行进一步的改进。这个 这项研究的主要预期成果是一种去除水资源中1，4-二恶烷的高性能生物工艺。根据成功的初步研究，预计这项新技术将比目前市场上提供的任何1，4-二恶烷处理技术更简单、更有效、成本更低。最重要的是，这项研究旨在为保护和补救饮用水供应提供一个有价值的工具，从而保障公共安全和环境的可持续性。 公共卫生相关性：我们饮用水的质量直接关系到人类的健康和安全。一种可能的人类致癌物质1，4-二恶烷已经在美国各地被发现，我们目前缺乏有效的技术来减轻它所构成的威胁。这项建议旨在通过开发一种新的高性能水技术来将1，4-二恶烷降解为无害产品来满足这一需求，从而保护公众健康。

DESCRIPTION (provided by applicant): Across the United States, water suppliers and managers are finding dangerous levels of 1,4-dioxane in water. This compound has been used for decades in a wide range of applications including as (1) a solvent in paints, varnishes, and prints; (2) treatment agent in artificial leather, (3) ingredient in pesticides and fumigants, (4), purifying agent in pharmaceuticals, and (5) solvent in resins, oils, plastics, adhesives, waxes, and cement. 1,4-dioxane is a probable human carcinogen at extremely low levels in water (parts-per-billion). It is highly soluble and thus travels extensively in underground water systems Most importantly, no conventional water treatment technologies can remove 1,4-dioxane from water. There are only two routes of eliminating 1,4- dioxane in water: UV or hydrogen peroxide coupled with ozone oxidation (i.e. advanced oxidation), and biological degradation. The energy and chemical costs of UV and chemical oxidation processes are often prohibitively high. There is also a significant risk of producing harmful by-products (such as carcinogenic bromate) and these technologies have limited applicability in certain circumstances Biological degradation also suffers from a number of drawbacks, including process stability, the need to induce degradation, limited performance, clogging, performance sensitivity, and the production of sludge or secondary waste streams. If these problems can be overcome, however, biological treatment offers a promising method of completely degrading 1,4-dioxane into harmless products and ensuring the integrity of the environment. The proposed research is founded on two novel discoveries. First, a high-rate biological treatment pathway has been found that apparently does not require pre-induction. This discovery may significantly simplify the treatment process. Second, this pathway can be utilized in a new high performance bioprocess that may overcome most or all of the engineering obstacles faced by conventional biological treatments. Specifically, the proposed research builds on and certifies these initial successes by conducting a series of laboratory (kinetic) experiences using 1,4-dioxane alone and in the presence of a co-contaminant, trichloroethylene (TCE). A continuous-flow bioreactor prototype is then designed and constructed. This model is tested extensively over several months using actual groundwater from a contaminated site to determine its specific performance under a range of operating conditions. These performance parameters are used to design a larger pilot-scale reactor that will undergo further refining in a field site in the next phase of research. The primary intended outcome of this research is a high performance bioprocess for eliminating 1,4-dioxane in water resources. Based on successful preliminary studies, it is expected that this new technology will be simpler, more effective, and less costly than any 1,4-dioxane treatment technology available on the market today. Most importantly, the research is intended to provide a valuable tool for protecting and remediating drinking water supplies, thus safeguarding public safety and environmental sustainability. PUBLIC HEALTH RELEVANCE: The quality of our drinking water is directly linked to human health and safety. A probable human carcinogen, 1,4-dioxane, has been found across the United States and we currently lack effective technologies to mitigate the threat it poses. This proposal aims to meet this need by developing a novel high performance water technology to degrade 1,4-dioxane into harmless products, thus protecting public health.