Vibrating hearth burners

Abstract

The invention relates to vibrating hearth burners. Three problems exist in known such burners, these being uniformity of fuel combustion; ash discharge; and over-heating of the grate. To meet the first of these, the present invention provides a burner in which the grate (30) and the vibrating mechanism (10,16) cooperate to decelerate the movement of fuel along the grate (30) as it travels towards the discharge end. This results in a build-up of ash towards the discharge end providing a substantially uniform thickness of fuel/ash on the grate (30), and a substantially uniform pressure drop across the grate (30). The provision of an ignition grate (32) is also contemplated to ensure that the fuel is ignited at the delivery end of the grate (30). To meet the second, the invention contemplates the provision of an ash return chute (54) incorporated in the vibrating grate assembly (8). Ash is discharged into the chute from the front end of the grate (30), and the vibrating assembly (8) keeps the ash in motion as it returns to the rear end adjacent the delivery end of the grate (30) for discharge. The third problem is mitigated by the construction of the grate with transversely laid bars (54). While additionally enhancing the air flow through fuel on the grate (30), transversely laid bars inhibit distortion of the grate (30) by differential expansion due to the heat generated thereon.

Dependencies are inferred from the claim text.