Level

The goal of a level control system is to maintain a constant aqueous suspension depth despite changes

Figure 1 Example of level control loop. LT, level transmitter; LIC, level indicator and control; LY, level D/A signal conversion; LCV, level control device; MAG, magnetic flow detector; FT, flow transmitter; FI, flow indicator; PID, proportional-integral-derivative; PLC, programmable logic controller.

Figure 1 Example of level control loop. LT, level transmitter; LIC, level indicator and control; LY, level D/A signal conversion; LCV, level control device; MAG, magnetic flow detector; FT, flow transmitter; FI, flow indicator; PID, proportional-integral-derivative; PLC, programmable logic controller.

in feed flow, floatable material concentration or air rates. An example of this control is found in Figure 1. In water-oil separation, a periodic level rise may be organized to dump an accumulated organic pad. The simplest method of controlling level is to adjust the discharge height of the underflow using a 'gooseneck' or alternative form of gravity control. If this is not possible, then the level must be detected and that signal used to control either a variable-speed pump or control valve through a controller device. Detection devices include floats; pressure, capacitance, conductance, and ultrasonic transducers, or combinations of these devices. The set point for the level is determined from the desired froth depth. Generally, the higher the level, the greater is the recovery of the floating component and the lower its content in the overflow

(froth product). In more complicated systems, the level control may be used with froth or oil pad depth data to control overflow grade, with flow-monitoring devices for predictive control based on incoming feed, or multiple monitors to compensate for variations in air rate or feed composition.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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