7 Mechanical transport and conveyor devices for feeding solids in biogas fermenters, namely, pneumatic and hydraulic transporters, conveyors and machines for conveying solids, all unrelated to electronic equipment; mechanical transport and conveyor devices for use in sliding floor bunkers and silos, namely, pneumatic and hydraulic transporters, conveyors and machines for conveying solids, all unrelated to electronic equipment; mechanical transport and conveyor devices for biogas installations and block-type cogeneration installations, namely, pneumatic and hydraulic transporters, conveyors and machines for conveying solids, all unrelated to electronic equipment; agitators for circulating liquid and semi-liquid media for biogas installations and block-type cogeneration installations, and crushing and pressing machines, namely, waste crushing machines, industrial machine presses for biogas installations and block-type cogeneration installations; installations for separating solid and liquid substances, namely, centrifuges; valves for controlling excess pressure and negative pressure in gas storage units and fermentation vessels, namely, pump control valves, valves for pumps, servo-valves; installations for process heat recovery in biogas installations, namely, heat exchangers being parts of machines for recovering process heat; installations for extracting nutrients and fertilizers, namely, centrifuges and extracting machines; valves for controlling excess pressure and negative pressure in gas storage units and fermentation vessels, namely, valves being parts of machines; valves for controlling excess pressure and negative pressure in gas storage units and fermentation vessels, namely, automatic valves, control valves for regulating the flow of gases and liquids; valves for controlling excess pressure and negative pressure in gas storage units and fermentation vessels, namely, automatic valves, thermostatic control valves for machines, for regulating the flow of liquids and gases; installations for carrying out biogas processes, namely, power plants