309 Highland Terrace
Prince Frederick, MD 20678
USA
Phone: (410) 535-6851
Fax: (410) 535-6846
Email:
Specializing in Sampling and Instrumentation, Corrosion,
Water and Steam Chemistry, and Failure Analysis
Serving the power industry since 1983
Wet Steam Enthalpy and % Moisture Monitor
Jonas, Inc. developed an on-line instrument (calorimeter) that continuously monitors the heat (enthalpy) and moisture (quality) contents
of wet steam. Applications include steam generation (desuperheating, moisture separation, efficiency, boiler carry-over), co-generation,
district heating, desalination, industrial processes (separation, condensation), oil recovery, gas liquification, erosion analysis,
steam for sterilization, and many others. The instrument is also applicable to other condensing fluids. This leaflet presents
a description of the Jonas, Inc. Enthalpy and % Moisture Monitor (Figures 1 and 2) as well at typical operating parameters.
Optional
use of this instrument is for collection of the moisture for chemical analysis (early condensate).
The objective of the Enthalpy and % Moisture Monitor is to measure the wetness of saturated steam in process piping. In order
to achieve this, the Monitor isokinetically samples the wet steam and uses a specially designed Moisture Separator to remove moisture.
The steam and condensate are cooled and the temperature, pressure and flow rate of each stream is monitored.
The outputs
from the flowmeters, as well as temperature and pressure indicators are sent to the Windows-based Monitoring Computer and used to
calculate the % moisture and enthalpy of the sampled steam (or other fluids). These values are then displayed and can be output
to a data acquisition system.
Isokinetic Sampling - For representative sampling of the gaseous and liquid phases, the EPRI Isokinetic
Sampling Nozzle, which has been a part of ASTM Standard D-1066, Standard Practice for Sampling Steam, since 1997, is used.
Figure 1. Schematic of Wet Steam Enthalpy and % Moisture Monitor
Copyright (c) 2009 Jonas, Inc. All Rights Reserved
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Sample Flowrate:
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0.05 to 25 L/min (condensed)
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Pressure:
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20 psia to 700 psia (1.4 to 48 kg/cm^2) (lower pressures can be achieved using
special sampling equipment)
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Temperature:
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500°F (260°C) max.
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% Moisture:
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0.1 to 20%
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Response Time:
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10 seconds
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Available Outputs:
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enthalpy,
% moisture, pressure, temperature, mass flow, BTU/hr or W/hr, cost/hr
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Signal Output:
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0 - 10 V, 4 - 20 mA, RS232 (specify when ordering)
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Figure 2. Jonas, Inc. Wet Steam Enthalpy and %Moisture Monitor
