Dissipation of Thermal and Chemical Disequilibrium in Hot Springs

温泉中热力和化学不平衡的消散

• 批准号: 0073963
• 负责人: Martin Schoonen
• 金额: $ 9.83万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-15 至 2002-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0073963&HistoricalAwards=false
• 关键词: Dissipation; Thermal; Chemical; Disequilibrium; Hot

SchoonenEAR-0073963Hot springs are environments characterized by thermal and chemical disequilibrium. The purpose of the proposed study is to determine the rates and mechanisms of abiotic processes by which the thermal and chemical disequilibrium is dissipated. The objective of this study is to obtain these rates through field studies of hot springs in Yellowstone National Park and possibly Lassen Volcanic National Park, complemented by a few laboratory experiments. As water flows away from the orifice or pool of hot spring, four types of interrelated abiotic processes take place. These are a) fluid flow b) cooling, c) gas transfer (e.g., O2 in gassing, H2, CO2 and H2S outgassing) , and d) chemical reactions in the water (e.g., travetine deposition, and hydrogen sulfide oxidation). A research strategy has been developed to obtain rates of these processes through detailed measurements of flow regimes (linear velocity and a measure of turbulence) in the drainages coupled with detailed temperature measurements to obtain cooling rates and chemical analyses to obtain the chemical evolution of the water as it flows away. The chemical analyses involve a determination of the concentration of dissolved gases (He, H2, Ar, O2, CO2, and H2S) and dissolved major ionic species. From the temperature profiles and concentration profiles the heat transfer coefficients and gas transfer coefficients can be derived. Because the determination of the gas transfer coefficients is crucial, a series of laboratory experiments is proposed in which the gas exchange coefficient of CO2 is derived by conducting a degassing experiment in a simple artificial channel with a flow regime similar to the drainages studied in Yellowstone. To keep these experiments simple they will be conducted at room temperature, but gas transfer theory is sufficiently well developed to allow extrapolation to higher temperature. The laboratory experiments will be conducted by undergraduate students.

温泉是一种以热化学不平衡为特征的环境。 拟议的研究的目的是确定的非生物过程的热量和化学不平衡是消散的速率和机制。 本研究的目的是通过对黄石国家公园和可能的拉森火山国家公园的温泉进行实地研究，并辅以一些实验室实验，以获得这些比率。 当水从温泉口或池中流出时，会发生四种相互关联的非生物过程。 这些是a）流体流动B）冷却，c）气体转移（例如，气体中的O2，H2、CO2和H2S的脱气），和d）水中的化学反应（例如，钙钛矿沉积和硫化氢氧化）。 已经制定了一项研究战略，通过详细测量排水系统中的流态（线速度和湍流度），再加上详细的温度测量，以获得冷却速率，并进行化学分析，以获得水流出时的化学演变，从而获得这些过程的速率。 化学分析包括确定溶解气体（He、H2、Ar、O2、CO2和H2S）和溶解主要离子种类的浓度。 从温度分布和浓度分布可以导出传热系数和气体传递系数。 由于气体传输系数的确定是至关重要的，提出了一系列的实验室实验中，CO2的气体交换系数是通过在一个简单的人工通道进行脱气实验与流态类似的排水研究在黄石公园。 为了使这些实验简单，它们将在室温下进行，但气体转移理论已经发展得足够好，可以外推到更高的温度。 实验室实验将由本科生进行。