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Quotes - Engineering - SalesCarbonated soft drinks, flavored and still water
Three exchangers that never see a pasteurizer
A carbonated soft drink plant has almost no pasteurization. Its exchangers dissolve and cool sugar syrup, chill blended product so carbon dioxide will stay in it, and warm treated water so a vacuum deaerator can strip the air out. Bottled and flavored water adds a hot water sanitizing loop and, on some still products, a light pasteurization before cold fill.
None of these duties is thermally hard. What makes them worth a page is syrup viscosity, gas coming out of solution on a warm wall, and one frame being asked to do two jobs.
Syrup, chilling and deaeration, one at a time
Syrup dissolving and cooling
Simple syrup is made by dissolving granulated sugar at 150 to 180 F in a batch tank or continuous dissolver, and the heat for that comes from a steam-to-water set or a U-tube shell-and-tube with low-pressure steam. Once dissolved, the 65 Brix syrup has to be cooled to 70 to 80 F for flavor blending, and that cooler is where syrup gets awkward: viscosity is about 30 cP at 180 F and 100 to 120 cP at 70 F, and a standard plate channel at that viscosity is laminar, low in coefficient and high in pressure drop.
The cooler is a wide-gap plate or a shell-and-tube with syrup on the shell side, sized on the cold-end viscosity with a 15 degree glycol approach. Tanker sweetener at 90 to 100 F is cooled on the same unit. Caramelized sugar on a hot dissolver wall is the usual fouling; hot water at 200 F rather than steam on the dissolver is the fix.
Chilling before carbonation
Carbon dioxide dissolves in proportion to pressure and in inverse proportion to temperature: a cola at 36 F holds about 3.5 volumes of CO2 at a pressure the filler can manage, and the same drink at 60 F needs nearly twice the pressure and foams at the fill valve. The product chiller is a gasketed plate exchanger on glycol that takes blended product from the proportioner at 60 to 75 F down to 34 to 38 F in one pass, at flows up to 800 gpm on a large line.
Two things are specific to this chiller. It is held under back pressure, 30 to 60 psi, so that any CO2 already in the water does not break out on the plates and gas-lock the channels. And the glycol approach is kept to 5 to 8 degrees; pushing glycol lower to shrink the chiller risks ice on the last plates when flow drops.
Deaeration and water treatment heat
Dissolved air in the water makes foam at the filler and oxidizes flavor, so treated water goes through a vacuum deaerator before the proportioner. The deaerator works better warm, and the water is preheated to 100 to 120 F on a plate exchanger against hot water or against the plant's warm return streams.
Bottled water plants run a hot water sanitation loop at 180 to 190 F through the filler and lines, made in a steam-to-water plate or shell-and-tube set, and some still products are lightly pasteurized at 165 to 175 F on a small three-section plate pasteurizer before cold fill.
The common mistake
Buying one plate frame to chill product on one shift and cool syrup on the next. The chiller wants a narrow channel and high velocity; syrup wants a wide channel and low pressure drop. Run syrup through a chiller pack and it channels, comes out warm and takes a shift to clean. HeatX quotes two units, or one frame with separate sections. Send the Brix, the flows and the outlet temperatures for each. Call and talk it through with an engineer: 1-805-484-2992
Soft drink and water process conditions
Syrup, finished product and treated water each get their own conditions here, since they rarely share a construction. Check the rows against your line and include your syrup strength and chilling target when you request a quote.
| Condition | Detail |
| Product | Sugar or HFCS syrup 55 to 67 Brix; blended product 10 to 13 Brix; treated water |
| Flow range | Syrup 5 to 60 gpm; product chiller 50 to 800 gpm; deaeration preheat 50 to 800 gpm |
| Temperatures in / out | Syrup 180 F cooked to 70 to 80 F; product 60 to 75 F to 34 to 38 F; water 55 F to 100 to 120 F |
| Hold | None; still-water pasteurization where used, 165 to 175 F for 15 to 20 seconds |
| Utility | Tower water then propylene glycol at 26 to 30 F; low-pressure steam or hot water on the dissolver and preheat |
| Approach | 5 to 8 degrees on the product chiller; 15 degrees on syrup |
| Construction | Gasketed plate for product and water; wide-gap plate or U-tube shell-and-tube for syrup |
| Finish / class | 316L on syrup and product, 304L on treated water; 32 Ra; food-grade drainable |
| CIP | Caustic at 160 F and sanitizer; hot water flush on the syrup side before caustic |
Common FAQs
34 to 38 F for most carbonated drinks at 3 to 4 volumes of CO2. Lightly carbonated products and flavored water can carbonate at 40 to 45 F with a higher carbonator pressure.
Wide-gap plate up to about 200 cP, shell-and-tube with syrup on the shell side above that or where the plant wants steam on the tubes for a dissolver. Standard plates channel on syrup below 80 F.
Usually not; it is treated, ozonated or UV-treated and cold filled. Flavored and vitamin waters with sugar or juice content are pasteurized like clear juice and often hot filled.
Air solubility falls with temperature and vacuum deaerators strip faster at 100 to 120 F than at 55 F. The preheat is a small plate exchanger, often on a warm return stream.
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