In order to improve the efficiency of the separation of an insulating liquid from a dispersum, in particular of water dispersed in oil, the electric conductivity of a dispersion having the dispersion constituents is measured continuously or discontinuously. An optimum frequency is calculated as a function of this conductivity. Pulsations of at least one pulsating electric field are thereby prescribed, this dispersion being led through said field. This frequency is preferably in the frequency range of >60 Hz-1 kHz. An electric field with a separating AC voltage can be arranged downstream of an electric field of a pulsating separating voltage of adjustable frequency in the flow direction of the dispersion, and an electric field of a pulsating charging DC voltage can be arranged upstream.

A method of removing harmful substances, particularly in the region of the earth's surface, wherewith an electrical voltage is applied to electrodes introduced into the soil. To remove the harmful substances, an electric field is established in situ by the electrical voltage, the intensity of which field is so great that harmful substances which are not electrokinetically transportable are broken up and/or degraded in place.

A unit for removal and prevention of scale deposits in a preexisting fluid containing system and destruction of microbes. The invention utilizes a.c. and d.c. superimposed electrical fields in combination with a sonic or ultrasonic transducer for supplying electrical and mechanical energy into a colloidal or particulate-containing solution. An impure fluid stream of reduced conductivity is passed between a cylindrical insulated electrode, having a first end and a second end, which electrode is axially centered within an insulated cylindrical electrode and housing. The configuration of the electrodes form a sealed cylindrical treatment chamber, having a inlet and an outlet for a fluid stream, and provide an electric field of a.c. waveforms superimposed on d.c. waveforms, comprising a resultant ripple voltage waveform. The ripple voltage is obtained by rectifying and filtering a standard and commercially available a.c. voltage. A sonic or ultrasonic transducer in combination with a deflecting cone axially affixed to the second end of the electrode is provided to emit sonic energy through the fluid stream for removal of scale deposits from the walls of preexisting closed fluid containing system and destruction of microbial organisms.

An in-well method removes hazardous organic substances including oily phases topping the groundwater (LNAPL) and dense liquid non-aqueous phases (DNAPL) occurring on top of the aquitard, irrespective of the viscosity of the pollutants, from groundwater and/or the perched water. In one embodiment, volatile organic pollutants are stripped from the contaminated water by an injected gas stream inside the well. In a second embodiment, the well acts as an electrode. By imparting an electrolytic current between the electrode well and a counter electrode, the organic pollutants are electrochemically degraded while at the same time within the well the degraded pollutants are stripped from the water. By the same arrangement metal ions and colloids can be caused to precipitate onto the well casing. Apparatus for carrying out these methods is also disclosed. In distinction from hitherto known solutions, the method and apparatus are applicable to low performing wells having a low natural throughput, shallow aquifers and in fizzurized rock.

Electrolytic treaters for treating highly conductive liquid media include a conductive housing structure which is fluidically sealed and has inlet and outlet fluid connections, a conductive electrode structure positioned within the housing structure, and a DC power supply connected to components of the housing and electrode structure in such a manner that the output voltage of the power supply is applied across a substantial portion of the liquid media to be treated to control the current flow from the power supply. In a preferred embodiment, the electrode structure is formed by a center electrode rod with a plurality of ring electrodes positioned coaxially between the center electrode rod and the housing. Each ring electrode is formed by a plurality of circumferentially spaced rod elements extending parallel to the center electrode. The rod elements in a given ring electrode are held in place by a plurality of annular spacer baffles which additionally affect the flow of liquid media through the treater.