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Quotes - Engineering - SalesPlant steam, made fit for food
Culinary steam is plant steam with the chemicals limited, the water knocked out and the particles filtered
Most food plants do not build a clean steam generator for every use. Where steam touches product, in an injection heater, an infusion chamber, a cooker, a tank sterilization or a deaerator, they make culinary steam from the plant boiler under 3-A Accepted Practice 609: boiler treatment limited to compounds the FDA lists for food-contact steam, an entrainment separator for carry-over, and a stainless filter close to the point of use. The header downstream of the filter is stainless, because carbon steel sheds rust into steam the filter just cleaned.
The Steam Generators page covers steam made from purified water. This page is about the other route: separator, filter, chemistry limits, and the condensate and steam quality tests.
Building a culinary steam supply
The chemistry limits
The boiler that makes culinary steam is treated only with compounds the FDA permits in food-contact steam, within the limits on that list. Volatile amines that ride with the steam to protect condensate lines are the usual problem: some are permitted at low limits, others excluded, and a plant sharing one boiler between culinary and general service lives with the culinary limits on the whole system. The alternative is a separate small boiler on RO water, or an unfired generator, which most plants choose once the culinary load passes a few thousand pounds per hour.
Separator, filter and the stainless header
Boiler carry-over is water droplets carrying dissolved solids and treatment chemical, and no filter stops it; a cyclone or baffle separator ahead of the filter does, dropping the water to a trap. The filter follows, close to the use point, in a 316L housing with a sintered or pleated stainless element rated to remove 95 percent of particles 2 microns and larger, with a differential gauge across it. Clean, the pair drop 1 to 3 psi; the element is changed when the drop doubles. Everything from the filter to the product is stainless and sloped to drip legs, and the pressure-reducing valve sits upstream so the element sees the lowest velocity.
- Separator first, trapped; filter second, within a few feet of the use point
- 316L housing, stainless element, differential gauge, spare element on the shelf
- Stainless pipe, drip legs and traps from the filter to the injection point
Condensate quality and steam quality testing
The plant proves the steam by condensing a sample and testing the water. A sanitary sampling condenser on the header draws steam, condenses it against cooling water, and passes the condensate through a sample cooler to 77 F. The condensate is checked for the treatment compounds at their permitted limits, for conductivity as a carry-over indicator and, where the site's program asks, for taste and odor against potable water. Steam quality itself is tested at the use point for dryness fraction, non-condensable gas and superheat with the same condenser and a calorimeter arrangement; a dryness under 0.95 means the separator is overloaded or the header is losing heat and needs insulation or a trap.
HeatX supplies the sampling condenser and sample cooler as sanitary exchangers, the coil rated for full steam pressure and the cooling side on chilled water so 77 F is reachable in summer.
The common mistake
Installing the filter at the boiler house and running 300 feet of carbon steel pipe to the injection heater. The steam arrives carrying rust from the pipe, the filter never saw it, and the first inspection finds iron in the product. The filter goes at the use point, the pipe downstream of it is stainless, and the separator ahead of it catches what the boiler sends. Call and talk it through with an engineer: 1-805-484-2992
Culinary steam conditions
What follows is the steam, separator and filter arrangement that fits food contact practice. Check it against your boiler treatment and use points, then send those details with the quote request.
| Condition | Detail |
| Fluid | Plant steam from a boiler on FDA-listed treatment; condensate quality tested |
| Flow range | 200 to 10,000 lb/h per use point; injection heaters take 5 to 10 percent of product mass |
| Temperatures in / out | Steam at 15 to 100 psig, 250 to 338 F; reduced at the use point |
| Hold | None; drip legs and traps at every low point |
| Utility | Plant boiler; no product-side utility |
| Approach | Not applicable; separator and filter pressure drop 1 to 3 psi clean |
| Construction | Cyclone or baffle separator, then a 316L filter housing with sintered or pleated stainless element |
| Finish / class | 3-A 609 practice; stainless header downstream of the filter; sanitary condenser and sample cooler for testing |
| Filter rating | Elements rated to remove 95 percent of particles 2 microns and larger |
| CIP / SIP | Filter element steamed in service; changed on differential pressure or schedule |
Common FAQs
Boiler compounds limited to those the FDA lists for food-contact steam, an entrainment separator, a filter at the use point rated to remove 95 percent of particles 2 microns and larger, and stainless piping from the filter to the product. The plant demonstrates it by testing the condensate.
For food contact under 609 the separator and filter are enough if the boiler chemistry meets the list. Pharmaceutical duties and plants that cannot control the boiler chemistry use a generator on RO or purified water instead.
When the differential pressure across it doubles from its clean value, or on a schedule the plant sets, typically every six to twelve months. The element is stainless and is steamed in service, so it does not grow anything between changes.
A sanitary sampling condenser at the use point condenses a measured sample; dryness fraction, non-condensable gas and superheat are calculated from it, and the condensate goes through a sample cooler to 77 F for conductivity and treatment compound tests.
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