Description

The 4,000 gallon concrete grease trap tank — model GT-4000 — is a precast interceptor for commercial kitchens, institutional catering and food processing. Its job is to slow wastewater down enough that fats, oils and grease separate and float before the flow reaches the sanitary sewer, where they would otherwise congeal into the blockages that municipalities increasingly fine businesses for. Listed at $5,500.

GT-4000 Specifications

Model: GT-4000
Capacity: 4,000 gallons
Material: precast concrete
Length: 14 ft
Width: 6 ft
Height: 7 ft 6 in
Weight: 39,600 lb
Construction: modular — base section, riser sections, top sections and lids
Internals: precast sludge weirs, oil weirs and outlet weirs fitted in the base section
Design: five-sided watertight construction
Access: rectangular frames with galvanised covers, or manhole frames with cast or ductile iron covers
Cover loading: 2, 4, 8 and 20 ton options
Handling: embedded lifters cast in; 1 ton universal lifters available
Price: $5,500

How the Weirs Work

The weirs are the whole mechanism. Wastewater enters, and the sludge weir holds back the heavy solids that settle to the floor. The oil weir traps the grease layer that rises to the surface. The outlet weir draws from the middle band of relatively clean water between the two and passes it on to the sewer. How many weirs a given installation needs is set by the project’s flow rate and loading, which is why they are cast into the base section to the design rather than fitted generically.

Modular Construction and Depth

The base section, risers, top sections, grade rings and covers stack to suit the invert depth on your site. That is what makes a precast interceptor practical: the same base can sit under two feet of cover on one job and six on another, with risers making up the difference and the access covers finishing flush to grade. Knock-outs are cast into the walls and broken out with a hammer for the pipe positions the design actually needs, and block-outs can be specified where a custom connection is required.

Installation Notes

At 39,600 lb this is a crane lift onto a prepared, level bedding — not a job for an excavator bucket and hope. Get the invert levels right before the tank goes in, because a grease trap installed out of level does not separate properly and cannot be corrected afterwards. Confirm the cover loading class against the traffic that will actually pass over it: a 2 ton lid in a delivery yard will not survive a truck.

Freight

Ships on a flatbed; crane offload required. Freight is quoted to your delivery ZIP code — send us the site address and access details for a price. For domestic and rural wastewater see the 1,000 gallon HDPE septic tank.