CAREER: Microbial-Based Engineering Approaches for Prevention and Treatment of Acid Mine Drainage: An Integrated Research and Education Plan

0239314 3月，本建议所述的研究旨在研究通过刺激异养微生物生长，将就地产酸降至最低的方法。假设在适当的条件下(即可降解的有机碳源)，异养细菌将能够与负责催化酸性矿山排水(AMD)产酸反应的铁氧化微生物竞争。这是一个尚未得到太多关注的领域，具有作为修复和预防技术的潜力。这项研究将提供对模拟极端环境中微生物群落结构的基本了解；然而，结果可能会被转移到受类似约束的其他极端环境中的群落动力学。本研究将通过实验评估添加有机碳底物对破碎或生物膜系统中矿物氧化的影响。本研究的具体目标是：1.在高比表面积体积比的实验室体系中，确定强化异养微生物生长对嗜酸微生物氧化矿物的影响。建立异养菌抑制产酸的作用机制(S)，并确定合适的条件来加强生物膜为主系统中异养菌诱导的抑酸。确定酸性环境中微生物铁还原和硫酸盐还原对酸性矿山废水生物修复的相对影响。评估添加有机碳底物对具有良好特征的AMD站点的酸生成的影响。拟议研究的长期和更广泛的科学和工程影响涉及开发防止和缓解酸性排水的新方法。虽然目前的应用侧重于酸性、含金属的水流的处理--通常利用化学沉淀--但拟议的研究将试图在需要处理之前防止就地形成酸。虽然拟议研究的一个主要目标是首先防止产生酸，但也将努力确定实现就地还原铁和硫酸盐的效果，特别是在低温环境中。与该项目有关的科学宣传活动将包括国际和平研究所参加区域公开会议，目的是教育公众与酸性矿山废水有关的问题。PI已经与加州区域水质控制委员会-拉洪顿地区的监管机构和水质科学家建立了工作关系，并将与这些个人合作传播实验结果。这项研究对教育的更广泛影响涉及开发互动实验，以纳入移动工程教育实验室(ME 2 L)。要求提供资金，以支持本科生为移动实验室设计和建造互动显示器。除了ME 2 L项目的效用外，这些演示还将被纳入北卡罗来纳大学的工程日和科学日项目，这两个项目旨在让高中生认真考虑科学和工程职业。除了这些以外展为基础的教育目标外，该协会还提议开发一个环境工程本科生和研究生课程系列，在工程课程中介绍环境微生物学的基础和应用方面。

0239314 Marchand The research described in this proposal aims to study methods for minimizing acid formation in situ by stimulating heterotrophic microbial growth. It is hypothesized that if given the appropriate conditions (namely, a degradable organic carbon source), heterotrophic bacteria will be able to out-compete the iron-oxidizing microbes responsible for catalyzing acid-forming reactions at acid mine drainage (AMD) sites.This is an area that has not achieved much attention and has the potential to be utilized as both a remediation and prevention technique. The proposed research will provide fundamental understanding of microbial community structure in a model extreme environment; however, results may be transferable to community dynamics in other extreme environments that are subject to similar constraints.This investigation will experimentally evaluate the influence of supplemental organic carbon substrate addition on mineral oxidation in fractured or biofilm-based systems. The specific objectives of the research are:1. Identify the influence of enhanced heterotrophic microbial growth on mineral oxidation by acidophilic microbes in laboratory systems with a high surface area to volume ratio.2. Establish the mechanism(s) involved in heterotroph-induced prevention of acid generation and determine the appropriate conditions to enhance heterotroph-induced prevention of acid generation in biofilm-dominated systems.3. Identify the relative influence of microbial iron and sulfate reduction in acidic environments for bioremediation of acid mine drainage.4. Assess the influence of organic carbon substrate addition on acid generation at a well-characterized AMD site.The long term and broader scientific and engineering impacts of the proposed research involves the development of new methods for both prevention and mitigation of acidic drainage. While current applications focus on treatment of acidic, metal-containing water streams - typically utilizing chemical precipitation - the proposed research will attempt to prevent acid formation in situ before treatment is required. While a primary goal of the proposed research is to prevent acid generation from occurring in the first place efforts will also be made to identify the efficacy of achieving in situ iron and sulfate reduction, particularly in low temperature environments.Scientific outreach activities associated with this project will include participation of the PI in regional public meetings aimed at educating the public about issues associated with acid mine drainage. The PI has already developed a working relationship with regulators and water quality scientists at the California Regional Water Quality Control Board - Lahonton Region and will work with these individuals to disseminate experimental results.The broader education-based implications of this research involve the development of interactive experiments for incorporation into the Mobile Engineering Education Laboratory (ME 2 L). Funds are requested to support undergraduate students while they design and build interactive displays for the mobile lab. In addition to their utility for the ME 2 L program, these demonstrations will also be incorporated into Engineering Day and the Science Day programs at UNR, two programs aimed at getting High School students to think seriously about careers in science and engineering. In addition to these outreach-based education goals, the PI has also proposed to develop an undergraduate and graduate coursework series in environmental engineering that introduces fundamental and applied aspects of environmental microbiology in an engineering curriculum.