CASE STUDY: Catalyst Changeout Project

PROBLEM

During a TAR (Turnaround) in 2018, a customer performed a catalyst replacement on their dehydrogenation reactors. To safeguard the catalyst and environment inside the reactors, climate control equipment was necessary. The customer requested a continuous air supply that met the following specific conditions: a dew point of 7°F-25°F or lower, relative humidity of 10%-15%, and a dry bulb temperature of 55°F-60°F or lower. Additionally, the equipment needed to achieve three to five volume changes per hour within the system. To achieve this, air had to be supplied to various locations, such as nozzles and manways. The vacuum equipment would also be operating at a rate of 3000 CFM (cubic feet per minute) during the vacuuming activities.

SOLUTION

To meet the specific requirements of the customer, ERS-Cat devised an engineered solution utilizing a combination of portable power, mechanical air conditioning, dehumidifiers, chillers, heat exchangers, and oil-free air compressors. While it was possible to achieve the desired dryness using only dehumidification equipment, the workers operating inside the reactor had temperature as a primary concern.

To address this, multiple 40T air conditioning units were placed in line with 5000cfm dehumidification units, resulting in a total of 10,000cfm of conditioned air. Custom-built high-static machines were employed to ensure the delivery of conditioned air through 350' of ductwork, generating over 10" of static pressure.

In order to achieve the specified dew point, an additional 3000cfm of air was introduced through multiple oil-free compressors. The aftercooled oil-free air was then fed into desiccant dryers to lower the dew point to -70°F. To achieve even lower temperatures, a small chiller and tube and shell exchanger were added to cool the air stream.

OUTCOME

By employing this comprehensive setup, ERS-Cat was able to fulfill the customer's requirements for temperature, humidity, and dew point control during the catalyst replacement process in the dehydrogenation reactors. These conditions were maintained throughout the entire duration of the project which lasted approximately 2 months. ERS was able to meet all client objectives protecting their $10 million catalyst investment.