Abstract: Methods and an apparatus for measuring gas flow with greater reliability than earlier single-rotor and double-rotor turbine meters and dual turbine meter systems are disclosed. The apparatus comprises two independent rotors, in close proximity of each other, housed in the same meter body, but isolated from the effects of each other. No pressure and temperature correction are needed for accuracy performance comparison between the two rotors. Because of the two rotor averaging technique, the reliability of the volume totalization is greatly improved over earlier double-rotor and single-rotor designs.

Abstract: Two types of boilers for generating high pressure steam from gaseous effluents containing abrasive and corrosive solids are provided. Both types of boilers are vertical boilers of the fire-tube type with the gas flowing within the boiler tubes and with the water and steam surrounding the boiler tubes.In one type of boiler according to this invention, the solids-containing gas is downfed through the boiler tubes with the gas emerging from the tubes and impinging on a concave, conical deflector and a convex nose cone located below the deflector. The deflector and nose cone serve to disengage solids from the gas.In the other type of boiler according to the invention, the solids-containing gas first impinges on a baffle plate which serves to disengage solids from the gas. The solids flow down for removal, while the gas flows up the boiler tubes to generate steam.