Abstract: Distribution of pollution reducing agents within an effluent at the effective temperature window for effective gas phase reaction is greatly improved. A two-phase mixture having fine droplets of liquid, e.g. a NO.sub.x reducing agent such as aqueous solutions of urea or ammonia, dispersed in a gaseous component, such as air, is injected into the effluent an sonic velocity to achieve a distribution of particles of sizes effective to uniformly reduce NO.sub.x within the zone of effective temperature while not producing a significant level of droplets so large that they survive beyond the temperature zone.

Abstract: The invention relates to a device for atomizing liquid with the aid of gas or for comminuting gas into small bubbles with the aid of liquid, in which the gas and the liquid are joined into a two-phase mixture in a mixing chamber and mixed, and the inflow speeds and volumetric flows of the individual phases are selected such that the outflow speed of the two-phase mixture is equal to the characteristic sonic velocity. An essential feature is that to maintain the mixing ratio, the outlet cross section is adjustable.

Abstract: Measuring the mass flow of a liquid gas pumped from a storage tank to a consumer through a measuring station, includes the steps of throttling the flow of the liquid gas by a throttle in the measuring station; measuring the flow of the liquid gas according to the relationship ##EQU1## WHEREIN M is the flow rate, C and m are instrument constants evaluated by calibration, .DELTA.p is the head difference and .rho. is the liquid density; maintaining the delivery pressure of the liquid gas higher than its vapor pressure plus the maximum momentary head difference at the throttle; and compensating for the temperature-caused liquid density variation, including the steps of measuring the temperature of the liquid gas by a semiconductor having a resistance/temperature curve and adapting the curve to the density/temperature curve of the liquid gas.