Sewer Pump Station

[antonio09]

I need to know the following. How i can size a sewer pump station of a new hotel complex. I have to option:

a. Use the total unit fixture discharge an change it to GPM in the table of demand.

b. Use the demand in galons per day per person in the hotel and estimate the peak demand (more and less 4 times).

The problem is the following: the quantity is very different in both option. Could anybody explain how i can size the pump capacity. (option a or b)

 

[BigInch]

Use 2, for option A, 4 for option B. No... seriously, why don't you post this on the water treatment and distribution forum?

 

[trashcanman]

Flow rate coming out = flow rate going in. What is the potable water demand of the hotel? That is your answer.

 

[LHA]

Option b, with a Peak Factor of 4 will do it.

Option a would seem to yield an unnecessarily conservative result, as if every fixture was opened/flushed/operated at precisely the same time.

BUT, if this is for a Hotel chain, from jobs I've done for Hotel and restaurant chains, they will have diurnal sags and peaks from other similar bldgs. Use that, I'm suprised that isn't spec'd by them; it was on the last few I've done.

Engineering is the practice of the art of science - Steve

 

[BigInch]

Trashcanman, Outflow can be higher than metered inflow, if large quantities of beer is consumed on hotel premises.

 

[bimr]

Estimate the population capacity of the hotel and use 100 gallons per capita per day as the wastewater flowrate. That will give you the average daily flow. Multiply times 4 for the peak hourly flow.

ref: Viessman & Hammer, Water Supply and Pollution Control

 

[PEDARRIN2]

If the hotel has a pool area, you should investigate the need to account for the backwash on the pool water treatment system.

This can be a large plug flow that could exceed the estimated peak flow if only considering occupant load. I have seen the use of a surge pit or tank to minimize the large short term flow requirements from the treatment system.