摘要 |
<p>Fumigation of grain in a storage facility having a plurality of grain silos (13) is effected from a single source (10) of a mixture of a carrier gas and a gaseous fumigant. The single source is connected to a single gas supply duct (11), to which gas inlet ports (16) of the silos are also connected. The connection between each gas inlet port and the duct is provided with a respective valve (14) and a respective orifice plate (15), which is adjusted so that the pressure drop across the orifice plate into the silo is substantially greater than the pressure drop across any other component between the gas source and the silo. With this arrangement, the flow rate of gaseous fumigant through the grain-containing silos in the facility suffers only a minor perturbation when a valve between the gas supply duct and a silo is opened or closed. This minor perturbation can be readily compensated by returning the gas pressure in the duct to its previous value. <IMAGE></p> |