The Snyder Industries 120 Gallon Vertical Double Wall Liquid Chemical Storage Tank (SKU SII-5700102N51) is a self-contained primary-plus-secondary containment unit molded in high density linear polyethylene (HDLPE), finished in black, and rated to a 1.9 specific gravity. The double-wall construction places a sealed inner tank inside an integral outer shell, so the tank itself supplies the secondary containment that aggressive chemical service demands - no separate berm or basin required - in a 34 x 34 inch footprint and 51 inch height. With 120 gallons of working capacity, this is a vertical storage tank built for tight rooms and loadout pads where a stand-alone containment structure is impractical.
Will this double wall tank handle my chemical?
The inner tank is HDLPE carrying a 1.9 specific gravity rating, and that number is the whole point. Max rated contents weight is 1,902 lb across 120 gallons - about 15.85 lb per gallon, versus 8.34 lb per gallon for water - so the shell is structurally rated to hold product up to roughly 1.9 SG. A standard 1.5 SG vertical tank simply cannot carry the densest chemistries below, such as 98% sulfuric acid, 50% ferric chloride, or 50% and 60% ferric sulfate. There is no higher-tier tank to step up to for this duty - the 1.9 SG rating is the appropriate spec, so do not under-spec it. Always confirm your chemical against the OEM chemical-resistance chart at your specific concentration and temperature before committing to service. Full of water the tank weighs roughly 1,001 lb; size the pad, anchoring, and floor loading to the 1,902 lb max figure, not the water figure - at the 34 x 34 inch footprint that is about 238 lb per square foot to hand your structural contact. The Tank Sizing Calculator and Tank Sizing Guide help confirm size and fill weight against your duty cycle.
Fittings and access - match them to your chemical
Per the technical drawing on this page, this tank is configured with a 14 inch PE threaded/vented lid and a manway with 11-3/8 inch access for filling, cleaning, and inspecting the inner tank. Treat every bulkhead, valve, and gasket you add to those ports as a verify-before-you-buy item: the HDLPE shell is compatible, but the connection materials are what fail. Match each fitting body (PVC, CPVC, PP, or 316SS) and each elastomer (EPDM, Viton, or Aflas) to your chemical's row in the table below before adding the tank to your cart. See the technical drawing on this page for fitting locations and the manway detail.
Chemical compatibility
This is an HDLPE inner tank rated to 1.9 specific gravity. The pairings below come from the OEM chemical-resistance chart and are concentration- and temperature-specific, so verify your exact conditions before ordering. The single most common mistake is running an EPDM gasket where the chemistry demands Viton or Aflas. Watch these:
- Viton gasket required (EPDM will fail): Hydrochloric Acid (37%, PVC), Hydrofluoric Acid (48%, PP/PVC), Hydrofluosilicic Acid (26%, PP/PVC), Hydrogen Peroxide (50%, PVC), Phosphoric Acid (85%, PVC), Sodium Hypochlorite (<16.5%, PVC), Sulfuric Acid (98%, CPVC body)
- Aflas gasket + 316SS body: Peracetic Acid (30%)
- 316SS body: DEF (32.5%, EPDM)
- PP/316SS body, EPDM: Propylene Glycol, Zinc Orthophosphate
- PVC/PP body, EPDM: Sodium Bisulfate, Sodium Bisulfite
- PVC fittings, EPDM gasket: Acetic Acid (60%, PP/PVC), Aluminum Sulfate (50%), Calcium Chloride (40%), Ethylene Glycol (100%), Ferric Chloride (50%), Ferric Sulfate (60%), Ferrous Sulfate (20%), Magnesium Chloride (30%), Polyaluminum Chloride, Potassium Carbonate (50%), Potassium Hydroxide (saturated), Sodium Carbonate (30%), Sodium Thiosulfate (40%), Urea Solution (50%, PP/PVC), and Ozonated Water (up to 10 PPM)
Browse the full Chemical Compatibility Database for the complete picture. If you are sizing for spill protection and freeboard, the guides on Snyder Captor double-wall tanks for SPCC 40 CFR 112 compliance, freeboard sizing per ASTM D1998, tank level gauge selection, and spillover redundancy engineering walk through the engineering.
Freight
This vertical double wall tank ships LTL from the Snyder plant in Marked Tree, Arkansas, with freight quoted live to your ZIP. Get a number on your screen with the Freight Cost Estimator, or call 866-418-1777 and we will quote it for you and help confirm the right fittings and gaskets for your chemical before the tank ships.
