BEIJING CENTRAL GRAIN DEPOT

PH3ReCirc Fumigation Recirculation Systems in Sealed Silos


This 1997 project involved the design and installation of PH3ReCirc recirculation fumigation systems in four sealed silos at the (then new) Beijing Central Grain Depot.

The system was designed for use with phosphide tablets placed on aluminium trays in the silo headspace (rather than on or in the grain itself), with fixed fans and ductwork to produce a downward flow of air through the grain mass.

Special gas-tight grain inlet and outlet valves were designed and installed by GTS at the top and bottom of each silo, with the bottom valves incorporating a diffuser through which air+fumigant is extracted from the base of the silo and recirculated back to the headspace.

GTS undertook the design, coordination and project management for this project.


Two recirculation ducts can be seen behind the stairway outside the end bins.



Gas tight grain inlet valves above silos 

Recirculation Fans above the silos



Gas-tight valves under silos, with
diffuser and recirculation duct immediately above.