According an embodiment, a liquid storage system comprises a tank for storing liquid fuel, a vent pipe for providing communication between outside of the tank and a gas space above a level of liquid fuel in the tank, a nonflammable gas supplying apparatus for supplying the gas space with nonflammable gases, a pressure control apparatus installed in the vent pipe to operate responsively to the pressure difference between the gas space and atmospheric pressure so as to limit a pressure in the gas space to a predetermined range. The pressure control apparatus introduces ambient air outside the tank into the gas space through the vent pipe when a pressure in the gas space is lower than a predetermined lower limit, and discharge a gas from the gas space out of the tank through the vent pipe when a pressure in the gas space is higher than a predetermined upper limit.

According to one embodiment, a substrate processing apparatus includes a tank that stores a treatment liquid; a liquid level pipe connected to the tank such that the treatment liquid stored in the tank flows therein, and configured such that the liquid level of the treatment liquid therein moves according to increase and decrease of the treatment liquid in the tank; a liquid level sensor that detects the liquid level in the liquid level pipe; an air supply pipe for supplying a gas to a piping space above the liquid level in the liquid level pipe; and a controller that determines whether there is erroneous detection of the liquid level sensor based on a detection result obtained by the liquid level sensor in response to the movement of the liquid level in the liquid level pipe caused by supply of the gas to the piping space from the air supply pipe.

A container may be supplied with an incompressible fluid. For example, the container may be partially or completely prefilled with the incompressible fluid. The container may be supplied with a flow of compressible gas via a first valve. The first valve may regulate the flow of the compressible gas supplied to the container based on a pressure setting of the first valve. A second valve may release the incompressible fluid from the container as the container is filled with the compressible gas and in response to a pressure of the container being greater than a pressure setting of the second valve. The pressure setting of the first valve may be greater than the pressure setting of the second valve.

The invention relates to the automatic reloading of the gas space of a hydropneumatic accumulator. An apparatus for readjusting the load of the gas space includes a pressurized gas source connected via an air system to a loading check-valve and a reinjection valve controlled by a unit for calculating a cycle for reinjecting gas into the gas space.

According an embodiment, a liquid storage system comprises a tank for storing liquid fuel, a vent pipe for providing communication between outside of the tank and a gas space above a level of liquid fuel in the tank, a nonflammable gas supplying apparatus for supplying the gas space with nonflammable gases, a pressure control apparatus installed in the vent pipe to operate responsively to the pressure difference between the gas space and atmospheric pressure so as to limit a pressure in the gas space to a predetermined range. The pressure control apparatus introduces ambient air outside the tank into the gas space through the vent pipe when a pressure in the gas space is lower than a predetermined lower limit, and discharge a gas from the gas space out of the tank through the vent pipe when a pressure in the gas space is higher than a predetermined upper limit.

A vehicle, in particular a rail vehicle, includes a compressed-air-operated toilet device and a compressed air supply system which supplies compressed air to the toilet device during normal operation. The vehicle also includes an emergency compressed air source that is suitable for providing compressed air for continued operation of the toilet device in the event of a failure of the compressed air supply system.

A pressure supply system for a fresh water system is provided. The pressure supply system includes a water reservoir having a bleed air inlet and a water outlet. The pressure supply system also includes a water pump so as to load water, which is loaded with bleed air pressure, with a further pressure downstream until a predetermined nominal operating pressure range is achieved. As a result, the pressure supply system provides an increased redundancy by pressure generator assemblies which are based on different pressure generation principles.