Disinfection CLO2 electrical power demand

[BRIS]

The client wishes to change from CL to CLO2 to be manufactured on site from sodium Chlorite and HCL. water is desalinated water at 48 degree C volume is 50 Million gallons per day - dosing at 2 ppm, I am trying to prepare a budget estimate for the supporting infrastructure works. Question is does anyone have a ball park estimate for the electrical power demand of a CLO@ plant. I have been given a figure of 2MW electrical power demand for the chillers - This sounds excessive ?

 

[ashtree]

There are a couple of things to look at.

The chiller is not for the CLO2 production directly but for cooling of the desalinated water. However this is unusual because most RO membranes unless they are the heat sanitisable type used for dairy production typically have a 40-45 degree C limit.

The final decision would have to be very site specific but you might use an evaporative type cooler to achieve the cooling you need for this project. It could be an open cycle once through type unit or perhaps a closed lop unit with a heat exchanger. Raw water chemistry may well dictate this decision. Power would be needed for fans and pumps and for a plant of this size power demand will be considerable. The amount of temperature reduction, water quality, closed loop/open loop , ambient temperature and humidity will all influence the power demand.

Chlorine dioxide generation itself is not particularly energy intensive but will require pumps, mixers , valving and instrumentation, to operate and monitor the system. Without know specifics it is difficult to advise, but you will probably need to generate 600-700lbs of chlorine dioxide per day.



Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[BRIS]

Thanks for the reply - the project is in the gulf - 25% of the distillate is from MSF and the other 75% from RO. we are advised that the water can be received at up to 48 degree C -

Why is it necessary to cool the desalinated water ? I assumed that only the "motive" water being drawn off the supply and run through the plant would need to be chilled.

We do not need to get involved in the process - our task is to provide the infrastructure - electrical power supply, pumping stations reservoirs etc. The process plant will be designed and constructed on an EPC basis by others.

 

[ashtree]

The water going to the MSF may not have to be chilled but the RO water most likely would as this is above the temperature that RO membranes can typically tolerate. Likewise depending on how the desalinated water is going to be used the treated water may be too hot as well.

But this requirement would be the same regardless of whether chlorine or chlorine dioxide was being used.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[BRIS]

Thanks again - I am sorry for not being clear - we are receiving the water from the desalination plants the RO and MSF supply are blended and then disinfected - the current disinfection is by chlorine. The client wants to change to Chlorine Dioxide. Water is stored in reservoirs providing 3 days storage and then pumped into distribution. Our task is to provide the infrastructure reservoirs, pump stations etc. including standby diesel generator. The power demand we have been given for the CLO2 plant is 2 MW which appears excessive. We are told that the incoming supply may be 48 degree C - That will be for the supply from the MSF plant the supply from the RO plant will be less.

 

[ashtree]

Yes I agree.
The CLO2 plant would be very unlikely to be 2MW.
I would be suprised if it was 200kw.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"

 

[bimr]

Have you contacted a manufacturer of these systems?

http://www.google.com/url?sa=t&rct=...995QC97LWCj6_VdHg&sig2=x_rnlj18cGnMpGk7Hi03ow