Abstract: A process and apparatus for regulating an electrodialyzer having a stack of ion-exchange membranes (2, 3) immersed in an electric field, and including sampling the dilute solution at the discharge (6), measuring in a cell (12) the content of a predetermined ion substance of this sample, in particular the content of free cyanide, and driving by means of a processing unit (14) a pump (15) as a function of that content so as to add a solution containing the ion substances (free cyanides) in an amount inversely related to the measured content at the intake (5) of the electrodialyzer, thereby eliminating electrodialyzer shutdown and membrane clogging.

Abstract: A speed limiter for the regulation of the speed of an internal combustion engine wherein in addition to a first kinematic linkage chain between a manually operable acceleration pedal and an engine throttle is provided a second computer controlled kinematic linkage chain which can assume speed regulation control in such a way that the second chain can take over from the first when the first has maximally opened the throttle and without the first chain hindering the functioning of the second under the command of the computer as soon as the vehicle has entered the prescribed range of regulation. In one embodiment the second kinematic chain includes a pneumatic actuator coupled to the throttle and operable by means of the opening electrovalves as controlled by the computer in accordance with vehicle speed and acceleration. In another embodiment, the second kinematic linkage chain includes a reversible motor having a shaft rotatable under the control of the system computer.