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.

A technique is provided for incorporating pneumatic control in centrifugal microfluidics. The technique involves providing a chip controller that has pressurized fluid supply lines for coupling one or more pressurized chambers of the controller with ports of a microfluidic chip. At least part of the chip controller is mounted to a centrifuge for rotation with the chip. A flow control device is provided in each supply line for selectively controlling the pressurized fluid supply, and is electrically controlled. Bubble mixing, on and off-chip valving, and switching are demonstrated.

A method and a device for air injection into a vinification tank (1) use air injection nozzles (2) installed therein. A rule is applied for automatic variation of injections with time, by a coordinated and combined action of the nozzles, so that for each of the installed nozzles the delivered air jets may be modulated in duration and frequency and combined with the jets delivered by the other nozzles according to a programmable sequence.