Modularized assembly for bulk material analyzer

A bulk material analyzer of the type in which the bulk material is transported through the material analyzer assembly on a conveyor belt between at least one radiation source and at least one radiation detector, includes a plurality of lower and upper modules that contain radiation shielding material and are so shaped as to define a passageway for the conveyor belt between the upper modules and the lower modules when the upper modules are placed on the lower modules. A primary centrally located lower module also includes the radiation sources and a primary centrally located upper module also includes the radiation detectors. Some of the outwardly located modules contain less radiation shielding material. The radiation shielding material includes a plurality of personally portable blocks. The conveyor belt is supported by compressed air passed through central upper wails in the outwardly located lower modules. The lower modules contain alignment members on upward facing surfaces thereof and the upper modules contain alignment members on downward facing surfaces thereof that are complementary to the alignment members on the upward facing surfaces in order to enable the upper modules to be accurately placed on the lower modules. The lower modules each include a central upper wall bounded by outwardly inclined inner side walls to define a trough for accommodating passage through the passageway of a conveyor belt having a contour corresponding to the trough. The container includes apertures disposed beneath at least part of the passageway, and includes conduits leading to the apertures from a port adapted to be connected to a source of compressed air so that the conveyor belt can be at least partially supported by compressed air while passing through the passageway.