Snyder Industries 8500 Gallon XLPE Vertical Liquid Storage Tank with ASTM Certification in White

Sixty-seven tons of oxidizer on a ten foot circle

Cross-linked polyethylene is a different molecule from the linear grade: the chains are bonded to each other during molding, so an oxidizer that would slowly crack a linear wall has nothing to work on, and the same bonding is what lets the wall hold its shape twenty degrees hotter than a linear tank. A 1.9 wall on top of that resin is sized for a liquid nearly twice as dense as water, and 3,100 pounds is what that takes on this shell, 700 pounds more than the lighter cross-linked grade in the same mold; the HDPE tank wall thickness guide explains the D1998 sizing logic and why the headspace, where hypochlorite vapor lives, is where a wall ages, and the freeboard sizing guide works out the usable volume once thermal expansion is accounted for. Full, it puts 134,691 pounds on a 120 inch circle at the rating: an engineered slab in full contact under the whole floor, inside a berm sized to the tank, with the empty tank strapped against wind at two heights and the manway reached from a fixed platform with a rail. The tank sizing calculator works the volume out from feed rate and delivery interval, and the tank sizing guide covers the reserve; hypochlorite loses strength in storage, so the reserve is sized to turnover as much as to supply.

Grades on the 120 x 194 inch tank, and the sizes beside it

The N40 is the lighter cross-linked wall for oxidizers that never approach this density, the N48 the other heavy wall at this tank's weight, and the N46 a linear grade. The 5300600N40 is the cross-linked 8,000 on this base 8 inches lower, and the 5360100N40 lays 8,750 gallons of cross-linked resin down on a 142 inch base at 146 inches for a lower roof.

Comparing across brands too? Call 866-418-1777; we carry Norwesco, Snyder, Chem-Tainer, Enduraplas and Bushman and will say which one fits, or price the freight first.

Connections

• Access: 18 inch threaded, vented manway, 194 inches up; vent outside on hypochlorite and peroxide service, fill through a dip tube, and size the vent for a tanker's unload rate.
• Outlet: name the chemical when ordering so the bulkhead fitting matches it; a flanged transition, an expansion joint, and a valve supported off the slab, in PVC or a fluoropolymer for hypochlorite, never brass.
• Service limit: 140 F / 60 C.

The level sender is chosen for the chemical and read from the ground, not the platform; keep the manway closed against vapor loss, and shade the tank, because hypochlorite in sun loses strength faster. For a regulated chemical a single wall tank stands in a berm sized to it. Label it so the fire inspector and the workplace inspector read the same thing. Insulate or drain the outlet valve and the first run of pipe wherever the ground freezes.

Delivery day at the manway

A tanker's pump moves liquid faster than a manway vent can pass air, so either the vent is sized to the unload rate or the fill comes in through its own top bulkhead with a separate vent line. The fill pipe runs to the floor so the chemical does not free-fall and foam; on a shell this tall that is a long drop. Watch the first delivery from the first gallon to the last, checking the slab edge and the outlet fitting as the level rises, and the log takes the date and strength of every load that follows; for hypochlorite the log is also the turnover schedule.

What it holds in practice

Sodium hypochlorite bulk storage at a water or wastewater plant with a full reserve, hydrogen peroxide at industrial scale, dense oxidizers delivered by tanker, warm process chemicals a linear tank could not take, and water where the buyer wants the toughest wall in the line, including a fire reserve of the kind the fire-water reservoir design guide describes. One chemical to a tank, with a label the fire inspector and the workplace inspector both accept.

Getting it to the pad

At 120 inches across and 194 inches long on the deck the 7400000N42 ships as oversize freight on a flatbed at a lane rate; the freight cost estimator quotes the haul to your ZIP; what is listed is the price before freight. A crane sets 3,100 pounds upright on the slab; a forklift gets it off the truck but cannot stand it up. Water-fill it once to the manway, hold it, then drain and dry before the chemical connection is made. Write the fill date on the manway with a paint marker; it answers the first question anyone asks about a tank.