Hydrogen sulfide (H2S) gas – colorless and extremely toxic – is a significant threat in the process industries and is one of the most common and critical hazards at remote locations. Whether in upstream oil and gas production, tank farms, refineries, pulp and paper plants, or even water and wastewater, H2S can put personnel at risk, as well as damage property. H2S is particularly dangerous as concentrations climb over 100 ppm and approach “knock-down” levels. At these concentrations one breath of the toxic gas is sufficient to cause a worker to lose consciousness. At locations that do not have fixed gas detection, workers rely on their personal monitors for toxic gas protection, but these devices cannot always provide sufficient warning before a worker is overcome by gas.
At the same time, monitoring for H2S at remote locations with conventional fixed-point gas detectors is a huge challenge. Some sites are difficult or even impossible to protect with conventional solutions due to the significant resources required to install, commission, and maintain the instruments and associated power and communication infrastructure. On top of that, different combustible and toxic gases have varying vapor densities further complicating the installation and commissioning effort.
Unmonitored sites are not only a safety risk, they have poor operational efficiency since it’s very difficult to identify operational upsets; trips to the site must be aborted the moment any gas is detected by portable or personal monitors and meanwhile personnel are at risk.
The solution lies in wireless gas monitoring since it minimizes the costs and effort required to install, commission, and maintain conventional wired detectors, extends protection to new applications, allows the user to place gas monitors where they are needed without additional infrastructure, and integrates easily with WirelessHART® networks.
With the introduction of the Rosemount™ 928 Wireless Gas Monitor, Emerson has pioneered wireless gas monitoring for remote and challenging sites that meets the real-world needs of difficult applications and environments. The Rosemount 928 includes the following capabilities:
One example of an application that is ideally suited for wireless gas monitoring is remote oil tank storage. Most remote tank batteries are un-manned and contain little or no infrastructure to support power or communication wiring. These locations are also frequently the scene of worker injury or death due to H2S inhalation since toxic gases tend to accumulate in the headspace of tanks and may be released during remote work operations such as tank gauging, sampling, or emptying. Considering a common remote crude storage application of eight tanks contained by a bund wall with two low point sump pits – 10 hydrogen sulfide gas detectors could be installed, one on each of eight tank hatches and one at each low point sump. Not only does the installation of gas monitoring solution improve safety over a “do nothing” solution, when all maintenance and installation costs are taken into consideration over a 12-year period, a wireless gas monitoring solution is approximately half the cost of a conventional wired solution – saving the user over $140k.
There are many more applications – such as in downstream facilities like refineries or petrochemical plants, pulp and paper mills, and water and wastewater treatment facilities – where integrated wireless monitoring of H2S gas is critical. More information about wireless monitoring can be found here: www.Emerson.com/RosemountWirelessGasMonitor.
Do you have a location that challenges you where your plant and personnel could be at risk for toxic gas leaks?