The science of measuring and controlling variables is termed instrumentation. As the name suggests, the process involves using a wide variety of instruments. These are classified as any device that can measure amounts that are physically quantifiable. These instruments do not have to be extremely complex in design. For example, the ruler is an instrument to measure distance, and a simple thermometer measures temperature.
Instruments specific to petrochemical processing include platinum Resistance Temperature Detectors (RTD’s), P/I Converters, many types of level meters, chromatographs, and continuous gas analyzers. These instruments are essential to the day to day instrumentation at petrochemical plants, as it is impossible to gauge to the necessary extent by estimation alone. Human error is inevitable, but an instrument can easily be calibrated or replaced.
Now that you understand the definition of and tools used in instrumentation, you should also understand the necessity of it. Temperature and pressure meters serve to ensure that the environment stays safe for both the chemicals being processed and the employees of the plant. Heat is a very well-documented activator in chemical reactions. If the temperature rises to unusual levels, this could spark an undesired chemical reaction that could prove catastrophic. The flow meter must measure how much oil is leaving the refinery, as it is a very volatile substance. Analytical instruments, such as the chromatograph, analyze the chemical make-up of the refined oil. This allows for the opportunity to make sure that the chemical make-up is correct, giving evidence that the process was correctly completed at all stages of refinement.