FLK Gas Sampling System - MPIP - Free

SQ251 FLK Gas Sampling Probe
1.4 Construction and mode of operation
The gas-sampling probe is basically constructed from four units:
• sampling chamber,
• cooling pipe with coolant return pipes,
• gas sampling pipe,
• mounting flange.
Legends: 1. Connecting flange for coolant feed 5. Covering flange
2. Connecting flange for coolant return 6. Cooling pipe
3. Measuring gas output 7. Sampling chamber
4. Mounting rail 8. Sampling opening
Fig. 2 FLK Gas Sampling Probe
The sampling chamber is located at the tip of the probe and has a sampling opening at the side. This arrangement
of the opening prevents the direct entry of the gas / dust mixture. The opening is positioned in a partial gas flow
and allows only relatively dust-free gas into the probe.
The cooling pipe in high temperature-resistant special steel is hermetically enclosed and contains the coolant
return pipe. The oval shape of the cooling pipe ensures a high vertical bending strength. The cooling liquid is
carried to the probe tip via two feed pipes and flows back in the intervening space on the outer pipe. The two feed
pipes are fastened at the probe head with a flange and can therefore be disassembled separately and without
problem. A specially developed, synthetic heat transfer fluid is used as the coolant. This liquid has a very high
boiling point and a high heat absorption capacity. The operating temperatures of over 200 °C obtained with the
fluid are higher than the flue gas condensation point and acid dew point of the process gases. The coolant feed /
return hoses are connected to the probe via ball valves, enabling the probe to be removed without loss of coolant.
The gas-sampling pipe is a pipe arranged centrally in the cooling pipe at a distinct separation. The gas enters
through an opening situated in the sampling chamber. This produces a slightly lower dust content in the gas.
When high levels of contamination occur, this pipe can be easily cleaned. As with the two coolants return pipes,
the gas-sampling pipe is joined to the cooling pipe via flange joints and can therefore be easily disassembled.
The mounting flange provides the mechanical joint between the gas-sampling probe and the furnace inlet
chamber or the precalcination chamber. When an automatic device is used for inserting and withdrawing the
probe, the joint cannot be made using a screw-connected flange.
Copyright ® SIEMENS Page 34 04/04