forms a separated space 4 and when outflow takes place after a separated space has been opened to the outlet duct in spite of these disadvantages in relation to the preferred embodiment a more homogeneous treatment result is obtained than with conventional continuous technology because the majority of the energy applied is applied in controlled forms when the flowing medium is located in the separated spaces 4 this embodiment has the advantage that it is less expensive to construct than the embodiments described above with pulsed fields and can be used when a lower degree of homogeneity of the energy quantity applied to the flowing medium is required arranged around the separated spaces 4 are three pairs of electrodes 6 these constitute the source for generating the electric field each of the electrode pairs surrounds a respective separated space the electrode pairs are arranged with the positive electrode on one side of a separated space 4 and the negative electrode on the other side of the space 4 each electrode pair therefore surrounding at some time a respective separated space it is of course possible within the scope of the invention to vary the number of spaces 4 and electrode pairs the electrode pairs generate an electric field in the separated spaces 4 the separated spaces 4 are rotated and translated in the pump housing 5 so that the pumpable substance 3 accommodated in the separated spaces 4 is moved in the direction in which the rest of the pumpable substance 3 accommodated in the remaining part of the container 1 is moved this takes place however without.