Converting Boiler steam rating from Kg/hr to Liters of water capacity

Hi there

Can someone help, I have a steam boiler, and have the KG Per hour steam rating the boiler can acheive (15,000kg/hr) , and need to convert that to the water capacity the boiler will hold

thanks

[JohnS]

Originally Posted by The Stalker

Hi there

Can someone help, I have a steam boiler, and have the KG Per hour steam rating the boiler can acheive (15,000kg/hr) , and need to convert that to the water capacity the boiler will hold

thanks

As cold water, 15000 kg is about 15000 L. However, I assume this is a closed system, the steam flows to a radiator or other load, is condensed and returned to the boiler. So the same water may make several trips per hour through the steam system and return being counted (as kg of steam) several times.

The water capacity will depend on the level of water needed in the boiler for best operation, and the amount out in the pipes as steam and condensate. I don't see a way to calculate it from the steam rating.

Thanks for the reply

The boiler is a industrial steam boiler, which uses the steam for the process on site ( brewing boooz ) in this case

in the past I have always been given the steam rating in LB/HR and have used the following;

boiler capacity - 15000 lb.hr x 2 Devided by 10 x 4.54 = water capacity of 13620litres

it has seemd to work so far, what do you think?? and would you just times the kg by 2.2 to get the lb rating?

thanks

[JohnS]

Originally Posted by The Stalker

Thanks for the reply

The boiler is a industrial steam boiler, which uses the steam for the process on site ( brewing boooz ) in this case

in the past I have always been given the steam rating in LB/HR and have used the following;

boiler capacity - 15000 lb.hr x 2 Devided by 10 x 4.54 = water capacity of 13620litres

it has seemd to work so far, what do you think?? and would you just times the kg by 2.2 to get the lb rating?

thanks

Without associated units, I am having trouble identifying the nature or validity of the formula. I will guess from "litres" that Imperial, not US, gallons may be involved. That leaves me stuck on the factor of 2. The division by 10 would appear to convert the rating to Imperial gallons of water, and the multiplication by 4.54 (s/b 4.546) to liters or litres. The factor of 2 seems incorrect unless it is judgmental and accounting for losses throughout the system.


The real question: is condensate returned to the boiler? If not, you keep processing new water to steam, and 15000 kg/h of steam requires 15000 kg/h of new water (plus additional to offset any steam losses along the way) 15000 kg of water is about 15000 L (true at 4 °C, reasonable approximation from 1 - 20 °C)

[JohnS]

Oh, I had a thought on the "2."

How do you process your water? I assume you can't use tap water due to mineral content which would scale up your boiler. Most water treatments use considerably more raw water than they produce boiler water. 2:1 is not unreasonable, with the wastewater having twice the mineral content. But I'm just guessing here.

Hello John

I think you are possibly correct with the assumption of the water treatment, also I think they will use de-mineralised water, or softner of somekind to fill the boiler.

the condensate I think is just wasted, so the boiler will have to keep replenishing its supply.

so I think maybe the boiler will hold around 30,000ltrs as I poredicted before.

I have just sent some figures through to the customer, and will find out in due course if I was right, I will let you know to put your mind at rest

many thanks

HI, I am trying to compare two electric steam humidifiers where their generating capacities are given in kg/h and the other in gal/h. Can any one help me with a conversion so that i may compare their capacities. Thanks for any help.

[JohnS]

Originally Posted by Unregistered

HI, I am trying to compare two electric steam humidifiers where their generating capacities are given in kg/h and the other in gal/h. Can any one help me with a conversion so that i may compare their capacities. Thanks for any help.

For the cold water you add, it is near enough to 1 kilogram per liter (just below boiling, it is 0.95 kg/L). Multiply the gallons by 3.8 (more exact is 3.7854) to get liters and use 1 kg/L.

Thank you for the help.