Biomass feedstocks (e.g., plant biomass, animal biomass, and municipal waste biomass) are processed to produce useful products, such as fuels. For example, systems are described that can convert feedstock materials to a sugar solution, which can then be fermented to produce ethanol. Biomass feedstock is saccharified in a vessel by operation of a jet mixer, the vessel also containing a fluid medium and a saccharifying agent.

An example fluid moving device for manure agitation in a pit located beneath a confinement building can include: a boom extending vertically into a pump-out wall of the pit; and a mechanism for extending horizontally into a main chamber of the pit to provide agitation. In some examples, the device can also include a self-propelled mechanism for moving along a surface.

An example fluid moving device for manure agitation in a pit located beneath a confinement building can include: a boom extending vertically into a pump-out wall of the pit; and a mechanism for extending horizontally into a main chamber of the pit to provide agitation. In some examples, the device can also include a self-propelled mechanism for moving along a surface.