A Handheld Sampler for Collecting Organic Samples from Shallow Hydrothermal Vents

Abstract

his study describes a new handheld sampler, specially designed to be deployed by scuba divers, to collect fluid samples from shallow hydrothermal vents. The new sampler utilizes a syringe-like titanium sampling bottle with a regulated filling rate to collect samples. The filling rate regulation mechanism of the new sampler was studied. Through theoretical analysis and simulation, it is found that the filling rate can be regulated by either an orifice or an annular gap on the sampler. Further study indicates that the orifice is superior to the annular gap, since the former has a much lower requirement of machining accuracy. Moreover, the filling rate regulated by the orifice is independent of temperature and ambient pressure. The new sampler also features a compact structure, simple operation, and gas-tight performance. Efforts were made to minimize the organic carbon blank of the sampler by careful selection of the materials that may come into contact with the fluid samples. The sampler has been tested at the shallow hydrothermal vents off northeastern Taiwan. High-purity organic samples were successfully collected.