Methods and apparatus for a desiccant saturation monitoring system having a body with a first portion configured to hold a desiccant material and a second portion configured to position a sensor in relation to the desiccant material. A light source can irradiate the desiccant material and the sensor can detect irradiance from the desiccant material for at least one wavelength to determine saturation information for the desiccant material.

The apparatus for producing liquid water from ambient air includes a lower frame and an upper cover defining an inner space, and at least one air inlet in the lower frame. An adsorption and desorption module is arranged in the inner space with a bed of adsorbent material. A ventilator varies between a first mode in which it imposes vertical forced circulation of the ambient air, and a second mode in which the upper cover acts as a condenser for the ambient air. A valve is arranged in the upper cover to allow the ambient air to flow from the inner space to the outside environment when the ventilator is in the first mode, the valve being otherwise closed. An electronic unit switches the ventilator selectively into the first mode during a period of night time and into the second mode during a period of day time.

Process for producing biomethane from a biogas stream including methane, carbon dioxide and at least one impurity chosen from ammonia, volatile organic compounds, water, sulfur-based impurities (H.sub.2S) and siloxanes. A biogas stream is dried, the at least one impurity is at least partially removed by solidification and removal of the impurity. The methane and the carbon dioxide contained in the biogas obtained from the second step are separated so as to produce a biomethane stream and a CO.sub.2 stream.

A dehumidifying element includes a plurality of sheets that have moisture adsorption and desorption properties and that are stacked on top of each another. At least some of the sheets each have an irregular shape. The sheets each contain a hygroscopic agent having properties of a re-moistening-type glue that exhibits adherence when adsorbing moisture and that solidifies when being dried. The sheets are bonded to each other by the hygroscopic agent.

Embodiments may include a hydrogen sulfide scrubber system that includes a charging chamber, a reaction vessel, and a treated gas trap. Embodiments may include a mobile vehicle, vessel, or platform that includes a mobile vehicle, vessel, or platform with a mounted hydrogen sulfide scrubber system. The hydrogen sulfide scrubber system is configured as previously described. Embodiments may include a method of using a hydrogen sulfide scrubber system.

A bypass for an air dryer having an inlet, a prefiltration stage having a drain valve to purge contaminants, a pair of inlet valves in communication with the prefiltration stage to control the flow of compressed air through the desiccant towers, and an outlet coupled to the pair of desiccant towers. The bypass may be a bypass valve that is normally open to the outlet when the air dryer is unpowered and pilotable to be a closed to allow air to flow to the prefiltration stage when the air dryer is powered. The bypass may be a three-way valve that is normally coupled to the outlet and that may be piloted to connect to the prefiltration stage when the dryer is powered. The bypass may also be a check valve that opens in response to pressure in the inlet to allow compressed air to flow directly to the outlet.

Air purification and dehumidification apparatus includes a first cooler that cools air introduced through a first inlet, a first rotor that primarily adsorbs and absorbs VOCs and moisture contained in the air cooled by the first cooler, an air conditioning unit that cools or heats the air primarily purified and dehumidified by the first rotor, a blower that moves the air cooled or heated by the air conditioning unit, a second rotor that adsorbs and absorbs VOCs and moisture remaining in the air moved by the blower, a second cooler that re-cools the air secondarily purified and dehumidified by the second rotor, a first heating unit that heats air that is introduced through a second inlet and is then supplied to the first rotor, using sequentially solar energy and electric energy, and a third cooler that condenses air containing the VOCs and moisture that are released from the first rotor.

A first aspect of this work relates to water harvesting in power plants. A water adsorbent material is driven through adsorption-desorption cycles using waste heat from a power plant to harvest water from ambient air. In a preferred embodiment, metal-organic-framework (MOF) powders are used as the water adsorbent material for this application. A second aspect of this work relates more generally to rapid adsorption-desorption cycling of MOFs for various applications.

Disclosed are a disease diagnosis device and a diagnosis method thereof. The disease diagnosis device includes a pump for pumping a respiratory gas, a first pre-treatment portion connected to the pump and removing moisture and bad breath in the respiratory gas, and a volatile organic compound (VOC) detection portion connected between the first pre-treatment portion and the pump to detect VOCs in the respiratory gas.

A CO.sub.2 separation system configured to separate CO.sub.2 from mixed gas containing CO.sub.2 includes a CO.sub.2 separator, a CO.sub.2 collector, and a pressure difference generator. The CO.sub.2 separator includes a separation membrane configured to separate the CO.sub.2 from the mixed gas, and a separation-membrane upstream chamber and a separation-membrane downstream chamber demarcated by the separation membrane. The CO.sub.2 separator is disposed to cause the mixed gas to flow into the separation-membrane upstream chamber. The pressure difference generator includes at least a negative pressure generator. The negative pressure generator is disposed on a gas path of the permeating gas that connects the separation-membrane downstream chamber and the CO.sub.2 collector.