The Snyder Industries 5500 Gallon Double Wall Vertical Chemical Storage Tank (SKU SII-5660000N43) is a White, high density linear polyethylene (HDLPE) tank rated for liquids up to 1.5 specific gravity, built with an integral secondary containment shell in a single vertical footprint. It stands 172 inches tall on a 120 x 120 inch footprint, holds a nominal 5,500 gallons, and is engineered for the chemical-storage and double-wall containment duty buyers searching for a vertical storage tank or double wall tank are trying to solve. The inner tank carries the product; the outer wall captures a release before it reaches your slab or berm.
Will it work for your liquid and your slab?
Sizing comes down to two weights. Filled with plain water, this tank carries roughly 45,870 lb. At its full 1.5 SG rating, the contents alone can reach about 68,805 lb. Design the pad, anchoring, and any structural review around roughly 68,805 lb of contents plus the tank and fittings, not the water number, because chemical service is where the rating earns its keep. The tank's dry weight is not listed here, so confirm it on the technical drawing on this page and add it to your load plan. Run your exact fill level and liquid density through our Tank Sizing Calculator, and if you are choosing between sizes, the Tank Sizing Guide walks through freeboard and headroom on a 172-inch-tall vessel.
Standard fittings per the technical drawing on this page include a flange, an 18-inch PE threaded and vented fitting, and a manway with 15-inch access. The 15-inch manway access is your entry point for inspection and level gauging; the 18-inch PE threaded/vented fitting handles fill and venting on a sealed chemical vessel. See the technical drawing on this page for fitting locations and elevations before you set piping or order valves.
Chemical compatibility
This is an HDLPE shell rated to 1.5 specific gravity. Always size the tank to the density of YOUR chemical, and match fitting and gasket materials to the liquid, not just the tank. As a quick rule on this tank: EPDM is the default gasket for the salts, carbonates, and glycols below; Viton is required for oxidizers and strong acids; and Aflas is reserved for peracetic acid. The pairings below come from the OEM chemical-resistance chart and are concentration- and temperature-specific, so verify your operating temperature and concentration against that chart.
Compatible with this 1.5 SG tank: Acetic Acid at 60% (PP/PVC fittings, EPDM gaskets); Aluminum Sulfate at 50% (PVC, EPDM); Calcium Chloride at 40% (PVC, EPDM); DEF at 32.5% (316SS, EPDM); Ferrous Sulfate at 20% (PVC, EPDM); Magnesium Chloride at 30% (PVC, EPDM); Sodium Carbonate at 30% (PVC, EPDM); and Urea Solution at 50% (PP/PVC, EPDM). Ozonated Water up to 10 PPM (PVC, EPDM) is also compatible, but it has no compatibility page yet, so confirm it against the OEM chart or call 866-418-1777 before you specify it. Running DEF (32.5% urea)? This tank is compatible, but DEF requires 316SS stainless fittings, not PVC, to keep the fluid uncontaminated.
Some chemicals need a heavier tank than this 1.5 SG model. Specify the higher 1.9 SG version for: Ethylene Glycol, Ferric Chloride, Ferric Sulfate, Hydrochloric Acid, Hydrofluoric Acid, Hydrofluosilicic Acid, Hydrogen Peroxide, Peracetic Acid, Phosphoric Acid, Polyaluminum Chloride, Potassium Carbonate, Potassium Hydroxide, Propylene Glycol, Sodium Bisulfate, Sodium Bisulfite, Sodium Hypochlorite, Sodium Thiosulfate, Sulfuric Acid, and Zinc Orthophosphate. Watch the gasket and fitting changes on the aggressive ones: sodium hypochlorite, hydrochloric, hydrofluoric, phosphoric, sulfuric, and hydrogen peroxide call for Viton (with CPVC fittings on sulfuric), and peracetic acid calls for Aflas. Confirm the full set on our Chemical Compatibility Database.
The mistake to avoid
The most common error on a double-wall chemical tank this size is sizing freeboard for water and ignoring thermal expansion and density. A liquid at 1.5 SG fills the tank with far more mass than water, and warm chemistry expands; both eat into usable volume. Our walkthrough on Captor double-wall freeboard sizing shows how to calculate the volume you can actually use. If this tank is part of an SPCC plan, the Captor SPCC 40 CFR 112 walkthrough covers how integral containment fits the rule, and pair it with the right level gauge for chemical service through that 15-inch manway and a layered high-level alarm and cutoff design to stop loadout releases before they reach the berm.
This Snyder tank ships LTL freight from the Lincoln, NE plant. Because freight on a vessel this size runs heavy, get an exact number with our Freight Cost Estimator quoted live to your ZIP, or call 866-418-1777 and we will quote it for you.
