Water Vapor Detector Tube

If the A1 liner in the graphite corrodes thru or breaks, water will leak into the graphite. Water vapor detectors in the helium recirculating system would advise the operators by alarms, as above, of such a failure. Means should be provided for identifying the tube at fault, such as by control rod actuation or... 

Catalytic activity for the selective oxidation of H2S was tested by a continuous flow reaction in a fixed-bed quartz tube reactor with 0.5 inch inside diameter. Gaseous H2S, O2, H2, CO, CO2 and N2 were used without further purification. Water vapor (H2O) was introduced by passing N2 through a saturator. Reaction test was conducted at a pressure of 101 kPa and in the temperature range of 150 to 300 °C on a 0.6 gram catalyst sample. Gas flow rates were controlled by a mass flow controller (Brooks, 5850 TR) and the gas compositions were analyzed by an on-line gas chromotograph equipped with a chromosil 310 coliunn and a thermal conductivity detector. 

Figure 24.14 The left panel is a plan of the testing area near the LENS (reflected shock) tunnel 1 — 8 test section 2 — TDL probe 3 — 4 nozzle M = 8-16 4 — 8" reflected shock tube 5 — fiber optic and signal line conduit 6 — data acquisition and 7 — TDL system optical table. The right panel is a schematic diagram of the setup used to record water-vapor absorption in high-enthalpy flows 1 — InGaAs detectors 2 — tunable diode laser Ai = 1400.74 nm 3 — ring interferometer 4 — tunable diode laser A2 = 1395.69 nm and 5 — HoO reference cell...

ASTM. 1991a. Standard practice for measuring the concentration of toxic gases or vapors using detector tubes. In 1991 Annual book of ASTM standards. Water and Environmental Technology. Philadelphia, PA American Society for Testing and Materials. 11.03 318-322. 

It is a fundamental requirement that liquefied petroleum gas should not contain free water (ASTM D-2713). Dissolved water may give trouble by forming hydrates and giving moisture vapor in the gas phase. Both of these will lead to blockages. Therefore, test methods are available to determine the presence of water using electronic moisture analyzers (ASTM D-5454), dew-point temperature (ASTM D-1142), and length-of-stain detector tubes (ASTM D-4888). 

Drier Tube—The reaction products include water vapor that must be eliminated prior to measurement by the detector. This can be accomplished with a magnesium perchlorate Mg(C104)2 scrubber or a membrane drying tube (permeation drier), or both. 

Water Vapor in Natural Gas Using Length-of-Stain Detector Tubes ... 

This test method covers a procedure for rapid and simple field determination of water vapor in natural gas pipelines. Available detector tubes provide a total measuring range of 0.1 to 40 mg/L, although the majority of applications will be on the lower end of this range (that is, under O.S mg/L). At least one manufacturer provides tubes that read directly in pounds of water per million cubic feet of gas. See Note 1. 

Detector tubes are usually subject to interferences from gases and vapors other than the target substance. Such interferences may vary among brands due to the use of different detection methods. Consult manufacturer s instructions for specific interference information. Alcohols and glycols will cause interferences on some water vapor tubes due to the presence of the hydroxyl group on those molecules. 

Detection. Automatic detectors are available which detect attack concentrations of vapors of hydrogen cyanide, cyanogen chloride and cyanogen bromide. Draeger tubes are also available, as are water testing kits. 

The major components of the mass spectrometer are a gas-handling manifold that enables the gas to be transferred from the ovens to the ion source, the ion source that consists of an electron impact source, magnetic mass analyzer with gap field of 6500 G, four different EM detectors, and an ion pump to ensure low pressure for the EMs. The gas handling system also included a controlled leak valve that could obtain Martian gas and feed the gas directly into the mass spectrometer for analysis. All the tubes in the gas handling system were heated to 35 C to ensure that there is no condensation of water and other volatile vapors on the hardware. 

Fission product noble gases entering the water-steam circuit in the event of a tube leak are completely volatilized and transported with the steam to the main condenser where they are extracted and released via the off-gas stack. This release is monitored by a continuously operating detector device located in the condenser off-gas line. Non-volatile fission and activation products which are transported over the leak to the water-steam circuit remain completely in the water phase of the steam generator by the action of the blowdown purification system their activity concentration is kept at a level which is controlled by the injection rate on the one hand and by the purification rate on the other. Because of the very low vapor pressures of these elements and their chemical compounds (dissolved ions or insoluble oxides/hydroxides), their transport to the steam under the prevailing conditions (270 °C, 7 MPa) is only possible by droplet entrainment. This means that partitioning between liquid and steam phases is proportional to the steam moisture content, which is usually well below 0.1%. 

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