5 replies to this topic

[guoyinyanliner]

​"Process Flow Diagrams (PFDs) or simplified P&IDs for utility systems, specifically thermal oil, chilled water, and hot water systems, for study purposes。

[breizh]

Consider these resources to support your work.

Water Cooled Chiller Design Data - The Engineering Mindset

Breizh

Attached Files

•  Chiller principle.xls   850KB   15 downloads
•  hot oil design guide.doc   687KB   16 downloads

[chemconsultant66]

Need certain guidance for induced draft cooling tower for efficient performance with minimum blow down and chemical consumption at modern time recommended COC. Say for 2000 m^3/hr. water circulation rate, 5degC approach, 10 DegC range, 29 Dec C wet bulb temperature. Kindly suggest best chemical treatment. Initially make is from RO water conductivity 4.6. Kindly suggest most cost-efficient chemical treatment scheme! This is all for process development and study purpose.

[Pilesar]

Since you are posting in the industrial professionals forum and not the student forum, I will assume you are an industrial professional and not a student. If optimizing chemical treatment is not part of the purpose of the study, then I would just select a treatment scheme that you know will work. Choose a treatment scheme that is already in place at the plant or nearby plants. Your Nalco Water representative (or equivalent) may be a useful resource. Another resource would be a cooling tower vendor who may do much of this design for you in anticipation of a future sale.

[breizh]

Hi,

To me your post does not make much sense. It all depends on the quality of the water. In other words, your blow down and chemical consumption is the result of the treatment. Don't play with them if you are not familiar with cooling water. 

Check with cooling water treatment company to have a proposal for treatment with achievable results on Blowdown and chemical usage.

Talk to big name who can provide equipment and regular monitoring outside Ph and conductivity continuous monitoring.

Breizh

Attached Files

•  evaporative cooling system.pdf   705.46KB   2 downloads
•  cooling tower basic calculations.pdf   652.75KB   8 downloads
•  Chemical Treatment for Cooling Water .pdf   4.2MB   2 downloads

[Plantcalckit.forums]

On the blowdown part of the question: the water balance sets the floor regardless of chemistry. At 2,000 m³/h and a 10 °C range the heat load is about 23 MW and evaporation is about 1.5–1.7% of circulation, so ~30–34 m³/h. Blowdown ≈ evaporation / (COC − 1): about 8 m³/h at 5 cycles, about 4 m³/h at 9.

With RO permeate at 4.6 µS/cm, scale isn't what limits your cycles. The water is very low in hardness and alkalinity, so it's corrosive, and cycles usually end up limited by chloride/silica build-up or biological control. That's the brief to give the treatment vendors Breizh and Pilesar mentioned: corrosion inhibition and biocide for very soft makeup at high COC.

Free makeup/blowdown calculator if you want to try different COC values: plantcalckit.com/tools/cooling-tower-water-balance/ (disclosure: I'm involved with PlantCalcKit).