Rotodynamic degassing pumping unit and rotor bearing design

Abstract

The present invention is concerned with degassing processes, and more specifically with a degassing apparatus and method for removing hydrogen sulfide and hydrogen polysulfides from liquid sulfur in a rapid and efficient manner to result in low residual hydrogen sulfide and hydrogen polysulfide levels. Utilizing a rotodynamic degassing pumping unit, a first fluid, typically in the liquid phase, is pumped or drawn under pressure or vacuum, while a second fluid, typically in a gaseous phase, is pumped or drawn under pressure or vacuum into the first fluid, effecting a chemical reaction. A rotary impeller having a plurality of blades is presented at a submerged location in the liquid sulfur surrounded by a draft-tube. The rotor (impeller) is divided into three distinct blade sections: a) a radial flow section; b) a mixed flow section; and c) an axial flow section. An overflow weir controls the depth of the liquid inside the degasser's housing. The overflow weir includes a corrugated type cross-section, comprising segments split longitudinally and welded lengthwise. The “wavy” or sinusoidal cross-sectional shape or trapezoidal or triangular shape (extending radially inwards) increases the length of the weir, which in turn minimizes the head required, and maximizes the capacity. A novel rotor bearing design is introduced as a means to mitigate excessive deflection of the main shaft. The design removes one of the two rotor bearings of the prior art and places two immersed bearings down the shaft.

Dependencies are inferred from the claim text.