Refineries and chemical plants have long been subjected to high costs incurred from failure of conventional sensors to accurately read moisture intrusion in feedstocks and hydrogen recycle streams, vital to optimizing product yield and catalyst life. Because typical analyzers, such as those based on surface absorption or adsorption, employ sensors that are exposed to harsh contaminants in the streams they monitor, timely and accurate moisture readings may be disrupted within a relatively short period of time. The disruptive operational life leads to substantial costs that can range from exorbitant consumables and maintenance to conceivably hundreds of thousands of dollars for premature catalyst recharging or untimely interruption of continuous processes.
Using tunable diode laser (TDL) technology has enabled the development of a new moisture technology called the laser-based spectroscopy moisture analyzer. Developed as a spinoff of NASA-JPL space technology by SpectraSensors, Inc., this optical device continuously samples reformer streams without coming into contact that avoids destructive contents such as hydrochloric acid.
The TDL-based moisture analyzer can provide refineries and chemical processors with a high return on investment based on avoidance of tangible costs, such as consumables, as well as extremely high intangible costs, such as catalyst recharging and process interruptions.
Tangible costs are greatly reduced through the use of the TDL-based moisture analyzer. While initial purchase price is somewhat higher, the reduced operating costs of this technology quickly overcome this initial investment quickly. The timely detection of excess water from feed streams enables refiners to lengthen the intervals between catalyst recharges in some instances. Lengthening the useful lifetime of catalyst represents a savings of hundreds of thousands of dollars or more, depending on specific plant requirements.
Speed and reliable measurements characterize TDL-based moisture analyzers that can detect moisture problems with high accuracy as quickly as one second, enabling practically instantaneous response. Examining operational costs over the life of an analyzer can eliminate costs associated with unreliable moisture measurements that include probe replacement, technician labor and overhead associated with maintenance and downtime.
The costs associated with redundant systems are equally straightforward to compute. The intangible costs of analyzer failure also can be examined. Although the probability of events such as catalyst failure or reduced efficiency or contaminated production may be low, the costs of these events are extremely high. For these reasons, the value of a reliable and fast measurement point goes far beyond the initial purchase price.