Heat exchanger with bulk material retarder system

Apparatus for controlling the flow characteristics of bulk material through a heat exchange structure, comprising:

• (a) a housing including a top wall and side walls,
• (b) an inlet in said top wall for receiving bulk material,
• (c) said side walls extending downwardly from said top wall terminating at a discharge funnel,
• (d) said housing defining an internal space for directing the flow of said bulk material,
• (e) said internal space including an upper zone and a lower zone,
• (f) a heat exchanger positioned in said upper zone,
• (g) an upper cascade plate extending between said side walls and situated between said upper zone and said lower zone,
• (h) said upper cascade plate including a plurality of openings formed therein,
• (i) a lower cascade plate extending between said side walls spaced from and positioned beneath said upper cascade plate,
• (j) said lower cascade plate having a plurality of openings, the number of openings being substantially less than the number of openings in said upper cascade plate, and the size of said openings being substantially greater than the size of said openings in said upper cascade plate,
• (k) a plurality of perforated spacer plates extending vertically between said upper and said lower cascade plates, and together with said upper and said lower cascade plates forming a plurality of intercommunicating cascade chambers,
• (l) each of said openings in said lower cascade plate forming a centrally located discharge passage for each of said cascade chambers, and
• (m) movable flow regulating means situated beneath said lower cascade plate for controlling the accumulation of bulk material in said cascade chambers.