The Macro Process and Product
The typical Macro system is comprised of two main components.
The first component is the inner unit that is a ½” thick polyethylene macro containment liner. It has an open top to allow waste, such as contaminated equipment and debris to be loaded directly into it or to overpack drums and overpacks.
The second component is an outer container, typically a standard metal container, that the inner macro liner sits inside of. The void space between the inner container and outer box is pre-filled with foam or vermiculite. The system can be designed for fissile or non-fissile, Type A, LSA-1, LSA-2 or strong, tight packaging depending on the needs of the particular waste form being macroencapsulated and shipped. The steel box can be qualified for up to 45,000 lbs. Custom containers can be developed for higher weight capacities.
Once loaded, the void space is filled with a filler, such as vermiculite and a ½” thick polyethylene lid is lowered onto the macro unit. A resistance wire heating element is embedded in the lid perimeter and mates up with the flange on the macro container. A weight distribution device is placed on the lid and a sealing weight is placed on that.
The lid is plugged into an Encapsulation Control Unit (ECU) and a button is pushed to initiate the process. The ECU automatically selects the required voltage and amperage. The electrical current flows through the resistance wires for a predetermined duration (e.g., 20 minutes) causing them to heat up and fuse the lid to the container body. The ECU signals the process is complete and successful.
The waste is now totally isolated from potentially leaching media in the environment by a half-inch of chemically inert polyethylene.
The whole process takes about two hours from loading to ready-to-ship.
Another novel approach in using the Ultra-Macro process is to use DOT- and UN-approved drums or boxes on the inside of the Macro liner. The inner steel drum or box provides the credit for meeting the transportation regulations while the outer liner provides the macro treatment and no additional steel box or drum is needed external of the macro liner. This can provide significant cost savings.