The disclosure relates to a preferably automated change system for changing a mixer, comprising a mixing device, having a mixer, for mixing at least two different components for a multi-component application agent for application onto a workpiece, and a handling device for moving the mixing device, wherein the change system comprises a change station for depositing a mixing device with a mixer to be changed and preferably for receiving a mixing device with a new mixer. The disclosure relates also to a corresponding changing method.

An automated system associates an agitator with a respective container for containing fluid, such as paint. The system includes a plurality of agitators; a storage area where the plurality of agitators are arranged; a moving device for moving the agitators at least between the storage area and the container; and a control system for controlling and coordinating the operations of the system. The agitators include a locking mechanism for removably fixing the agitator to the respective container.

An apparatus for use with a wastewater treatment tank is described. The apparatus includes a track, pipe modules coupled to the track such that the pipe modules are translatable along the track, and diffusers attached to the pipe modules. Each pipe module defines a respective partially curved mating surface, a respective partially curved mating cavity, and a respective gas passage passing through it. The respective partially curved mating surface of a first pipe module is inserted into the respective partially curved mating cavity of a second pipe module, while the respective partially curved mating surface of the second pipe module is inserted into the respective partially curved mating cavity of a third pipe module. Each gas passage of the pipe modules is in gaseous communication with the other gas passages of the pipe modules. At the same time, each diffuser is in gaseous communication with the gas passages of the pipe modules.

An auger protection system used in a stirring system is disclosed. According to a first preferred embodiment, an auger protection system is provided which protects augers on a stirring machine from breaking or bending. Accordingly to this first preferred embodiment, the auger protection system includes a switch which is enclosed in a housing and connected to a timer which supplies power to a gear motor that propels the unit around a silo. Preferably, the housing for the holding switch is attached pivotally to the structure on which the down auger is connected. Additionally, the auger protection system preferably further includes a spring which is connected to a pivot assembly and which extends horizontally and comes in contact with the down auger at one end.

An automated system associates an agitator with a respective container for containing fluid, such as paint. The system includes a plurality of agitators; a storage area where the plurality of agitators are arranged; a moving device for moving the agitators at least between the storage area and the container; and a control system for controlling and coordinating the operations of the system. The agitators include a locking mechanism for removably fixing the agitator to the respective container.