Free worksheet / Food-processing wastewater
For high-pH food-processing wastewater: lime cook water (nejayote) from masa and tortilla plants, and other alkaline streams that get acid ahead of solids removal or ahead of a biological step. Fill it in before you size a metering pump or order a tank, and you'll have the numbers a supplier needs to quote the acid package in one pass.
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A pH reading can't size an acid feed. pH is a logarithmic snapshot, and the acid a stream needs depends on how much alkalinity it carries. Two streams at the same pH can need very different doses. The worksheet starts from a bench titration of the real wastewater at its worst case, then runs the arithmetic:
Acid demand as pure HCl
W = Q × D × 8.34
W = lb/day of 100% HCl · Q = flow, mgd · D = design dose from the titration, mg/L as 100% HCl
Product feed rate
F = (Q × D) ÷ (C × SG)
F = gal/day of delivered acid · C = mass fraction of HCl in the delivered product · SG = specific gravity from the supplier's SDS
Metering pump range check
Fpeak ≤ Pmax and Fmin ≥ Pmax ÷ TD
Pmax = rated maximum output at your discharge pressure · TD = the manufacturer's published turndown ratio. Batch plants need the real batch profile, not a textbook peaking factor.
Materials, from manufacturer data. For HCl service, Poly Processing requires a fume-tight manway and venting to a scrubber on its XLPE tanks (SAFE-Tank double-wall: 110% containment). Blue-White publishes ratings for 10% and 37% hydrochloric acid. Graco rates FKM, FKM-ETP, FFKM and TFE/P seals "Good" for hydrochloric acid, concentrated included. Asahi/America's guidance for 37% HCl is PVC with FKM seals and vented ball valves for off-gas relief. The worksheet turns each of those into a line to confirm on the submittal.
Worked setting. The flow figures come from a real public record: a Central Valley masa plant's tentative Waste Discharge Requirements, which describe cook water at about pH 11, up to 48 batches a day of about 3,500 gallons, a 0.21 mgd monthly average flow limit, HCl dosed ahead of the hydro-sieve for scale control, and a biological step that needs pH 6–9 below 100°F. Read the full nejayote wastewater guide.
Draft Proposal Worksheet, not a procurement-ready specification. Final sizing, materials and dose point are the engineer of record's call and must be confirmed against the project's design documents and each manufacturer's published data.
James Riggins
LibertyCES — Liberty Chemical Equipment & Supply
One supplier for the acid storage, metering, transfer and valve package, with submittal-ready cut sheets and "or equal" comparisons. No charge to review a spec before it's issued.
(559) 395-5500 ·[email protected] ·[email protected] ·libertyces.com