Patented fast reactor cooling for major Turnaround at a large US refinery

A Houston based refinery wanted to cool their hydrotreating reactor quicker during a planned Turnaround.

Cooling was needed to enable faster entry into the reactor by Turnaround personnel to remove the deactivated catalyst.

Nitrogen is traditionally used to cool a hydrotreater fixed bed reactor, however this is an expensive and slow, taking around 5 days to cool the reactor catalyst down, meaning the refinery process is offline longer.

The faster the refinery can cool the catalyst down, the faster they can finish the Turnaround and get back to full production.

Aggreko Process Services (APS) partnered with the customer ahead of the turnaround to design and install a process system based on the anticipated design conditions and recommended a new approach using our unique patented method.

Aggreko engineers designed a system based on mechanical chillers, a shell and plate heat exchanger, centrifugal pumps, a process drum, power generator and associated piping to cool the reactor. We worked to install a network of stainless-steel cooling hoses to the plate side of a heat exchanger on site. Recycled hydrogen gas from the customer was then circulated to the same side of the heat exchanger.

This ensured that cold recycled gas from the exchanger could be directed to the reactor via a closed recirculating circuit bringing the temperature down quickly. An innovative solution saving time.

We reduced the catalyst cooling step by more than 50% allowing the refiner to eliminate 3 days from their Turnaround allowing a quicker return to full operations.

The accelerated project schedule combined with an attractive financial return, showcase Aggreko’s unique position in the market with this form of patented cooling. A previous Turnaround with this refinery’s reactor took around 125 hours compared to an impressive 45 on this occasion.

Depending on the size of the refinery and the scope of the Turnaround, an Aggreko Reactor Cooling project can return millions of dollars to a plant when you consider the lost profit opportunity, as well as the savings in labour and nitrogen.

The benefits were clear for the customer, who was happy with the delivery of the cooling solution. Other safety advantages such as a reduction in truck traffic on site and eliminating logistical placement issues at the reactor, reinforced that Aggreko solutions always deliver.