A weighted secret sharing and reconstructing method includes encoding the secret using a predetermined code, producing voices so that different weights are assigned to errors in an error vector according to locations of the errors, encrypting the encoded secret using the error vector and distributing the encrypted encoded secret to a plurality of participants. The nozzle system is elongated and includes a fixed shell and a movable shell movably supported by the fixed shell. The arsenic contained in the influent is thus removed by crystallization. A hydraulic piston applies pressure to the locking collar to actuate the locking collar to the locked position, wherein teeth on the locking collar engage corresponding teeth on the differential housing thereby fixing the differential housing for rotation with the locking collar and thus the side gears. A preload spring has a first end which is attached to the frame member, and a second end which is attached to the second end of the first hydraulic cylinder.