Packaged Steam Boiler Water is dirty

tc0624

My boiler is packaged steam boiler (8000lbs/hr) with natural gas fired. The boiler has just operated for 3 months, and the water sample from the boiler found dirty and cloudy as the image attached. The water in the feedwater tank is clean and no problem with the water source. We did blowdown constantly but the problem still exist. The steam is use for direct injection to processing food, and this kind of water quality has contaminated the steam and our product.
Can anyone help to suggest a solution to resolve it?

nicholas bonham-carter

What is the make of the boiler?
Was it piped strictly in accordance with the manufacturer's instructions?
Was it cleaned, (skimmed), after the installation?--NBC

ChrisJ

Please post some pictures of the boiler and the piping around the boiler.

There's a good chance it just needs another good cleaning. It takes a long time to wash all of the oils out of the block and new piping.

ratio

Is this a new install, or a replacement? If a replacement, how was the supplied stream from the old unit, satisfactory?

As mentioned, oils from newly installed piping & the boiler itself need to be mechanically (as in not chemically) removed, Google "boiler skimming".

It may be minerals from the water itself precipitating out as the water is heated. What is your makeup water source? I believe Dan Holohan offered a solution to that problem in his book "The Lost Art of Steam Heating", available at this website: run the makeup water through a sacrificial water heater to wring the minerals out into a cheap water heater instead of an expensive boiler.

Henry

A 12 hour wash is always required on a new steam boiler. Have you checked the water chemistry in the boiler? Sometimes too much of chemicals is worst than insufficient water treatment. I have a good number of years in the food industry. If you are direct injecting for pasteurisation or in baking, a S/S micro filter is required at each point of use. It is also a FDA requirement for some foods. I had one install that the filters would block after two weeks. After the blame going from the installer to the supplier to the maker, the boiler chemicals were the culprits.

EBEBRATT-Ed

May have to use a hx to get clean steam

Big Ed_4

When water turns to vapor it leaves the solids behind ..The solids are the minerals that are normally in the water source ... I was to believe , the steam used in process would be pure water.. Hmmm

ChrisJ

Big Ed said:

When water turns to vapor it leaves the solids behind ..The solids are the minerals that are normally in the water source ... I was to believe , the steam used in process would be pure water.. Hmmm

It should be, or extremely close to pure water.

Improper piping and or dirty water can cause things to be sucked up with the steam though.