Temperature recorder controller

Fig. 1. Fat sphtter. TRC, temperature recorder controller FLIC, Hquid level indicator controller PCV, pressure control valve and HCV, heat control valve.

Column Bottom Temperature. The bottom temperature is often controlled on the reboiler outlet line with a control valve in the heating medium line. The control point can also be on a bottom section tray. Care must be exercised in location of the temperature control point. It is recommended, especially for large columns, that a cascade arrangement be used. The recommended scheme has a complete flow recorder/controller (FRC) in the heating medium line including orifice and control valve. The set point of this FRC is manipulated by the temperature recorder/controller (TRC). This eliminates the TRC from manipulating the control valve directly (recall that temperature is the most difficult parameter to control). This makes for smoother control for normal operations. Also, it is handy for startup to be able to uncouple the TRC and run the reboiler on FRC for a period. 

Two furnaces were each fitted with a temperature recorder controller and high-temperature trip. The two recorders were side by side on the instrument panel in the control room, with the recorder for A furnace on the left (Figure 3-2). 

Tanks with vent hlters must be designed for pressures of -20 kPa and +100 kPa and must be equipped with a rupture disk. Tanks for hot loop and steam sterilizable line must be designed to withstand steam sterilization (121°C). A steam jacketed sterile vent hlter must be used to avoid condensation in the hlter and the vent hlter housing temperature controlled. The tank for hot storage is steam jacketed and insulated for temperature maintenance. Minimum instrumentation shall include level indication, temperature recording controller, pressure gauge, and pressure relief valve. 

There are two ways to answer this question. Let s first look at the reboiler. As the tower-top temperature shown in Fig. 4.1 goes down, more of the lighter, lower-boiling-point alcohol is refluxed down the tower. The tower-bottom temperature begins to drop, and the steam flow to the reboiler is automatically increased by the action of the temperature recorder controller (TRC). As the steam flow to the reboiler increases, so does the reboiler duty (or energy injected into the tower in the form of heat). Almost all the reboiler heat or duty is converted to vaporization. We will prove this statement mathematically later in this chapter. The increased vapor leaving the reboiler then bubbles up through the trays, and hence the flow of vapor is seen to increase, as the reflux rate is raised. 

FRC flow recorder controller TRC temperature recorder controller LIC level indicator controller PIC pressure indicator controller... 

Supervisory control and data acquisition Solid-state relay Self-tuning regulator Temperature recorder controller Transistor-transistor logic Zero order hold element... 

Temperature recording controller, board mounted (electric measurement)... 

Temperature recording controller and tenipeniture lecorder, combined instninient board mounted... 

PRC = pressure recorder controller TRC = temperature recorder controller TC = thermocouple V = viscometer... 

Flow record controller Temperature record controller Temperature indication controller Temperature recorder Pressure indication controller Level record controller pHIR Indication recorder... 

Temperature recording controller, boord mounted, resetting locally mounted flow indicoting controller (Atofe that Cehtri Stating should be shorn alongside airline to indicole cascade control)... 

FIGURE 18.52 Instrumentation diagram of a temperature control system for a stirred tank reactor symbols electrical instrument line, TT temperature transmitter, TRC temperature recorder-controller. 

For temperature recorder control, find the associated thermowell. 

The temperature recorder controller (TRC) holding the reboiler outlet temperature signaled the steam-inlet control valve to pinch back. 

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