如何测量沼气中硫化氢含量
| 为什么要测硫化氢THE REASON |
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Shale gas was produced by "fracking" i.e. hydraulic fracturing. The technique targets shale
gas, the natural gas trapped within deep rock layers. Much like historic
drilling rushes, the fracking craze of the past decade has been
characterized by wide speculation over reserve sizes, disputes over
valuable land rights, proprietary extraction technologies, and different
region-by-region legislation. The undeniable allure of domestic shale
gas--especially for countries dependent on foreign oil--has led to the
fast-tracked acceleration of fracking projects around the world. And due
to this "new frontier" fracking landscape, the shale gas industry is
filled with many eager players, with projects ranging from massive
operations to small 'wildcat' rigs in highly populated areas.
This variety of sources means that the shale gas can vary wildly in quality and composition--specifically, sulfur content. Yet the energy companies that purchase the extracted gas are still responsible for making sure the incoming feeds from fracking operations meet quality standards before distributing the gas to consumers. The logistical challenge is to validate sulfur content in these diverse gas sources without slowing distribution or increasing costs. |
| 测量方法 THE METHOD |
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The facility at which natural gas is physically delivered
from one company to another (i.e. from a frack site to a pipeline
operator) is known as a "custody transfer point." At this station, the
gas purchaser must measure hydrogen sulfide concentration in the feeds
or risk pipeline damage, work hazards, and providing contaminated gas
downstream to consumers. Using online UV spectrophotometers, the hydrogen sulfide concentration of an incoming shale gas feed is continuously monitored in real time; a multiplexed configuration uses a single analyzer unit to watch H2S levels in several incoming streams simultaneously. Furthermore, full-spectrum background correction (unique to Applied Analytics' OMA-300 Series) secures the measurement accuracy against the high variation in shale gas composition, specifically the fluctuation of chemicals that would cause cross-interference in a more rudimentary analytical system. Most importantly, the fully automated nature of these systems means that they are integrated at the custody transfer point with no effect on the process, other than seamless sulfur monitoring. |