Previous in Forum: Grout and Machine Vibration Next in Forum: Combustion dynamics
Anonymous Poster

# airconditioning question

09/08/2008 11:17 PM

hello sirs, kindly tell me how much tonnage of chiller (reciprocating) is required to chill the water tank of 40,000 litres,of water for cement factory,plzzz give me the exact tonnage of chiller

Interested in this topic? By joining CR4 you can "subscribe" to
Anonymous Poster
#1

### Re: airconditioning question

09/08/2008 11:54 PM

Impossible without knowing initial and final temperatures!!!!!!!!!!!

Also - is this simply a static cooling or is there a flow rate involved?

Anonymous Poster
#2

### Re: airconditioning question

09/11/2008 8:39 AM

For concreate cooling to transport them from batching plant to site, it has to be at 7C and will be around 11C when it is poured. And water is cooled by reciprocating chillers mostly procuired from Harrage having 30 TR x 7 = 200 TR actual cooling capacity air cooled chillers. For cooling 40 cu.mtr water from 35C to 7C, u require 2 insulated tanks of 20 cu mtr each filled with water. This water is circulated by pump @ 2.4 gpm per TR capacity from one tank to another thro the chiller. The final chilled water storage tank over flow into the initial storage tank which will b circulated by a pump again thro chiller till the temperature reaches 7C. THis is normally done in the night before the concreate mixing is started at Batching plant and takes about 8 hrs or so. The water at 7C is again pumped by another pump to mix with the concreate in the transporting truck.

The heat load can b calculated as per the following formulea:

Q = m x td where cooling capacity in btus/hr and mass is in lbs and Temperature difference of raw water and fhilled water is in F

Btus/hr = (40,000 /3.785412) x (95-45) x 8.3333333 x 60

where 3.7854 ltrs = 1 US galn. 95 - 45 is TD, 8.333... lbs is wight of 1 US Gaqlon water and 60 is to convert them to per hr.

Now the product of the above is 264170981 btus per hr

264170981 / 12,000 = 22014 TR

Now u have 200 TR Chiller, so the running hours to pull down the temperature is

22014/200 = 110 Hrs. If u want to pull it down in 8 hrs over night, then the capacity of chiller required is 200 x 14.

But in actual the temperature will be pulled down in less than 8 hrs, with 1 x 200 TR chiller alone of the above capacity. I have installed and seen such system

Anonymous Poster
#3

### Re: airconditioning question

09/19/2008 12:05 AM

1.You need to know the temperature of the water which is to be chilled

2. You need to know what temperature you want to chill the 40000 litre water to

3. You need to know over what period of time is required to chilled the water from it's initial temperature to the temperature you want the water to be for the process.

Know all tthe above yoy can calculate tthe tonnage refrigeration using the formula

Q=m flow l/s rate X Delta T X 4.19 kJ/kG