Abstract: A process is disclosed for treating a mixture of a solid and a liquid, the mixture including a contaminant. The process comprises the step of subjecting the mixture to cavitation wherein at least a portion of the contaminant is chemically decomposed. The process subsequently comprises the step of introducing a pre-determined biological species into the treated mixture to give a desired biological outcome, such as a biodegradation treatment, remediation or decomposition of the contaminant. Such a dual process can reduce the concentration of a contaminant to extremely low levels as well as achieve outcomes that the introduction of a biological species alone is not able to achieve.

Abstract: A process for treating a solid-liquid mixture by cavitation to decompose at least some contaminant associated with the solid particles, the contaminant either being absorbed into the pores of the solid or onto the surface of the solid particles. The process includes the step of subjecting the mixture to cavitation such that a portion of the contaminant is chemically decomposed. Typically the chemical decomposition occurs at the surface of the solid particle. Typically the cavitation process is an ultrasonic treatment step, although other cavitation processes are applicable, for example high shear mixing. The cavitation effect is capable of achieving physico-chemical changes at the particle surfaces. The localized high temperatures on bubble collapse (as high as 5000K) can decompose contaminant substances such as PCB and other hazardous materials including polybrominated biphenyl PBB), organochloride and organophosphate compounds, pesticides and the like.

Abstract: A process for treating a solid-liquid mixture by cavitation has been developed to decompose at least some contaminant associated with the solid particles, the contaminant either being adsorbed into the pores of the solid or onto the surface of the solid particles. The process includes the step of subjecting the mixture to cavitation such that a portion of the contaminant is chemically decomposed. Typically the chemical decomposition occurs at the surface of the solid particles, although the process can also occur to some extent within the poses near the surface of the solid material being treated. Typically the cavitation process is an ultrasonic treatment step, although other cavitation processes are applicable, for example high shear mixing. The cavitation effect is capable of achieving physico-chemical changes at the particle surfaces.

Abstract: A fluid meter has a central cylindrical section in which time-of-flight ultrasonic measurements can be made between acoustic transducers disposed in spaced apart enlarged end sections. The central section has a smaller diameter than do the end sections. Transitional regions join the end sections to the central cylindrical section. The transducers are located at least in part in the transitional regions. The transitional regions in the intermediate central section are generally shaped such that in combination with the shape and location of the transducers, pressure drops along the central section along with back-reflections of acoustic pulses from the transitional regions are reduced.