An environmental control system includes an air conditioning subsystem and a contaminant removal subsystem downstream of the environment to be conditioned. The contaminant removal subsystem includes: a first gas-liquid contactor-separator; a second gas-liquid contactor-separator; and a dehumidifier disposed either upstream of the first gas-liquid contactor-separator or downstream of the second gas-liquid contactor-separator.

An aircraft environmental control system includes means for mixing and conditioning bleed air from a bleed air input and recirculation air from an aircraft interior to provide mixed, conditioned air to the aircraft interior. The system also includes a first contaminant removal device and a second contaminant removal device arranged in a path of at least part of the recirculation air, prior to the means for mixing and conditioning, and a valve (SV1) arranged to alternate flow of recirculation air through the first and second contaminant removal devices.

A compact lightweight air filtration system is disclosed. The air filtration system includes a hydrophobic particulate/coalescing filter and a cleanable ozone converter housed in a housing with an inlet and an outlet. Air flowing from the inlet to the outlet passes through the particulate/coalescing filter element and then the cleanable ozone converter to remove particulates, aerosols, liquids, and ozone. The air filtration system may comprise a fuel tank inerting system (FTIS) filter assembly. The FTIS filter assembly may include a binderless media (no binder) suitable for use in high temperatures. The FTIS filter assembly includes a catalytic converter configured to adsorb one or more VOCs, such as Toluene, Propylene Glycol (C.sub.3H.sub.8O.sub.2), Pentanoic Acid, Butane (C.sub.4H.sub.10), Formaldehyde (CH.sub.2O), and Carbon Dioxide (CO.sub.2).

There is provided an apparatus for preparing a ventilation gas mixture for pilots and crew of aircraft, the apparatus comprising a first gas mixer feed configured to receive exhaled air from a person, wherein the exhaled air comprises carbon dioxide, a second gas mixer feed configured to receive an air mixture comprising at least one gas, and a gas mixing device configured to receive the exhaled air and the air mixture from the first and second gas mixer feeds and combine the exhaled air with the air mixture in the gas mixing device to form a ventilation gas mixture. The apparatus further comprises a pressure adjuster configured to increase the pressure of the exhaled air in the first gas mixer feed so that it substantially matches the pressure of the air mixture in the second gas mixer feed.

An environmental control system includes an air conditioning subsystem and a contaminant removal subsystem downstream of the environment to be conditioned. The contaminant removal subsystem includes: a first gas-liquid contactor-separator; a second gas-liquid contactor-separator; and a dehumidifier disposed either upstream of the first gas-liquid contactor-separator or downstream of the second gas-liquid contactor-separator.

An onboard rebreathing loop system resident on an aircraft for providing oxygen to aircraft personnel includes a ceramic oxygen generating system (COGS) module configured to receive an inlet air and output a high purity oxygen (O.sub.2) gas into a breathing loop and a carbon dioxide (CO.sub.2) scrubber module configured to receive exhaled air from the aircraft personnel and output a CO.sub.2-scrubbed air into the breathing loop. The high purity O.sub.2 gas and CO.sub.2-scrubbed air are mixed to form a mixed gas having a partial pressure of O.sub.2 suitable for breathing by the aircraft personnel. The onboard rebreathing loop system may further include an odor removal module, an air temperature and/or humidity control module to condition the mixed gas before breathing by the aircraft personnel, and a gas sensor module to confirm the partial pressure of O.sub.2 within the mixed gas before breathing by the aircraft personnel.

An aircraft contaminant removal system includes one or more membrane separators configured to absorb a contaminant from a cabin air stream into a liquid sorbent, desorb the contaminant from the liquid sorbent, discharge the contaminant in a contaminant stream, and return clean air back to the cabin. In some examples, the contaminant removal system includes a membrane scrubber-separator and a membrane stripper-separator, while in other examples, the contaminant removal system may include a single membrane separator configured to operate in a scrubbing mode and a stripping mode. The contaminant removal system may include a humidity management system configured to maintain a humidity of the clean air stream or water concentration of the liquid sorbent using one or more water sources of the aircraft or a thermal management system configured to maintain a temperature of the liquid sorbent using one or more heat exchangers fluidically coupled to an aircraft air stream.

An inerting system for aircraft including a gas circuit with successively at least one air inlet, a compressor and an air separation module. The air separation module includes an outlet for oxygen-enriched gas and an outlet for inerting gas. The air separation module includes gas permeation membranes resistant to a temperature greater than or equal to 100° C. and preferably 140° C., and the inerting gas outlet is connected to a turbine for releasing pressure and cooling the inerting gas.

An environmental control system includes an air conditioning subsystem and a contaminant removal subsystem downstream of the environment to be conditioned. The contaminant removal subsystem includes: a first gas-liquid contactor-separator; a second gas-liquid contactor-separator; and a dehumidifier disposed either upstream of the first gas-liquid contactor-separator or downstream of the second gas-liquid contactor-separator.

An aircraft environmental control system includes means for mixing and conditioning bleed air from a bleed air input and recirculation air from an aircraft interior to provide mixed, conditioned air to the aircraft interior, the system further includes one or more rotating wheels arranged in a path of at least part of the recirculation air, prior to the means for mixing and conditioning, the one or more wheels configured to remove one or more contaminants and/or moisture from the recirculation air before mixing and conditioning.