Cooling Tower Hydraulics

[syncrudewater]

I am sourcing a consultant who has experience with plant cooling water dynamics.

I am in charge of commissioning a new ICT 18 cell 828 mW cooling tower (design: 150,000 gpm) with 2 electric and 2 steam driven 55,000 gpm circulating pumps.

The new tower has to come online at the same time as a 5 cell 260 mW cooling tower (design: 79,035 gpm) is shutdown... in a working 250,000 bpd refinery:

- all units nust be kept operational
- water temperature and flow rate supplied must not be compromised
- circuating CW pumps must not be damaged
- high high and low low forebay levels must be prevented. Liquid levels must be maintained at/near NLL

The 2 towers are ~5300' apart and ~15' different in NLL elevation. Supply and discharge headers are 54" on the old and 72" on the new. The plant cooling water header between the towers varies through 54", 48" and 66".

After the old CT is down, we will install stopples in the CW headers, add 5 cells and 1 pump to the old tower, and re-commission it along with several new refinery units.

ICT has stated they have no experience with this type of swing-over, and doubt it has ever been done. The Fluor engineers have presented a credible execution plan that is now at Rev. 1, but before we take it to senior management we need to have it vetted by an alternate authority.

This is critical path: the new tower must be operational in early 2004. Basin has been hydro'd and tower construction is underway.

Bill Hopkins
Lead Operator - Water Systems
Syncrude UE-1 Project
Alberta Canada
robert.hopkins@ue-1.com
hopkins.robert@syncrude.com

 

[svanels]

I am no water authority but it looks like two of the new pumps could take over your current load. I suspect that the pumps are centrifugal pumps.

I would map the areas in acording to their need of water to determine the critical points.

If possible look for a major activity like a decoking to do the switch.

Keep a close eye on incoming/outgoing water temperature in the basins.

A rise of the incoming temperature in the new basins against a drop in the old basins is the main indication that the load is transfering.

Have an emergency fill of both basins in place to prevent running dry.

Have the new lines filled with water before start-up

These are some of the points I can think of.

Regards Steven van Els
SAvanEls@cq-link.sr