Eliminated Shutdown Thermal Oxidizer (TOx) by Manipulated Wave Signal of Flame Scanner with UV-IR Wave

Abstract

PP Gundih is one of the Central Processing Plant which operated in Pertamina EP Asset 4 – Field Cepu. One of the facilities in CPP  Gundih is Thermal Oxidizer (TOx) which used for processing / combusting acid gas which generated from sweetening gas  process to reduce air polution in many chemical plants that decomposes hazardous gas at a high temperature. For operate TOx,  there are some Instrument equipments supported to control, measure and protect during operation.

Previously, TOx in CPP Gundih used Flame Scanner with UV (Ultra Violet) Type to monitor firing operation inside TOx. Output data from Flame Scanner was used to control from PLC. PLC is hardware which have function to control and generate some data by using cause & effect matrix. Unfortunately, during 7 years operation, Flame Scanner which installed at TOx CPP Gundih always override because the signal strength from Flame Scanner was too low (less than 50%) and could not detect actual firing condition inside TOx and this issue was so dangerous because flame scanner triggered cause & effect for shut down system. If the operation didn’t do override, TOx will shut down and probably loss production because of this case.

By that case, Maintenance teams tried to solved the problem by manipulating wavelength range of Flame Scanner, concern range  of radiation. We replaced existing flame scanner from UV Type became UV – IR (Infa Red), which combination of UV and IR wavelength can cover wider radiation spectrum. All known electromagnetic radiations are customarily arranged monotonically according to their energy in a continuum called the electromagnetic spectrum. The electromagnetic spectrum spans many orders of magnitude in energy and, correspondingly, in frequency and wavelength. The optical radiation range is located between microwave radiation and X‐rays. The optical radiation range is composed, in order of increasing energy, of infrared, visible, and ultraviolet radiation. Fortunately, after replaced flame scanner by using UV-IR Type, the signal strength was high, above 80% and operation don’t do override again.