Intrusive probes

A series of tests were conducted in the furnace to compare CARS temperature measurements with those acquired with a suction pyrometer [84]. A suction pyrometer is an intrusive probe to measure gas temperature in a flame. The principle of the device is to insert the water cooled probe to the measurement point and draw furnace gases over a thermocouple located at the tip of the probe in an enclosure shielded from flame radiation. The gases are drawn at sufficient velocity to enhance the convective heat transfer to the thermocouple bead. Typically, the flow rate of furnace gases through the probe tip is increased until the thermocouple temperature no longer increases. At this point the thermocouple is assumed to measure the true gas temperature. The disturbance by such a measurement technique can be considerable in the near burner region where chemical reactions are occurring and there is heat release. 

EXPERIMENTAL METHODS, 264 Intrusive Probes, 265 Steady State Tracers, 267 Impulse Tracers, 269 Optical Tracers, 274 Chemical Reaction, 276... 

Measurement techniques for the gas phase in CFB risers are becoming increasingly more sophisticated and accurate, and many find application in industrial-size equipment. In this section, we classify the different methods into five categories intrusive probes, steady state tracers, impulse (non-steady state) tracers, chemical reaction, and optical tracers. No single tracer technique is capable of quantifying... 

Intrusive probes are robust and have been used to measure velocity profiles in industrial scale equipment. However, data interpretation is not straightforward, and... 

Corrosion monitoring is done directly on the pipe wall, and therefore gives more direct and representative information than traditional intrusive probes or coupons. 

Cody GD, Bellows RJ, Goldfarb DJ, Wolf HA and Storch GV 2000 A novel non-intrusive probe of particle motion and gas generation in the feed injection zone of the feed riser of a fluidized hed catalytic cracking unit, Proc. ASNEIMECE 2000, Orlando, Florida, US, Nov 5-12... 

Intrusive probes and coupons for monitoring corrosion and erosion... 

The technique has the advantage that it measures the actual corrosion taking place within the process system, regardless of process fluid type and with a high degree of sensitivity, without the need for access fittings, intrusive probes, and retrieval operations. Removal of the spool pieee for confirmation of the pattern and extent of corrosion being indieated is reeommended. This wiU normally have to coincide with a plant shut-down. 

The following three studies were performed injection velocity study, adiabatic compression study, and plastication study. Each study is detailed in the discussion section prior to presenting the results. For the studies a high flow polycarbonate (PC) resin was used, which was dried prior to processing. The barrel temperature profiles used for each study are available in Table 1. With the exception of the compression study, each of the runs was stabilized for 15 consecutive shots before data was recorded for five consecutive shots. For the injection velocity study and the screw recovery study the melt temperature was also measured with a hand held intrusive probe. Directly following data collection the injection unit was retracted, the machine was manually purged, and the melt temperature was measured using a hand held probe that had been preheated to the barrel temperature. 

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