A control process and apparatus provide feed forward control of stoichiometric proportions of hydrogen sulfide and ammonia to a thermal oxidizer and an ammonia scrubber, respectively. To account for unmeasured or uncalculated sulfur feed to the thermal oxidizer, a feed back measurement of sulfur dioxide and ammonia concentration is used to correct the flow rate of hydrogen sulfide to the thermal oxidizer and/or ammonia to the ammonia scrubber.

A control process and apparatus provide feed forward control of stoichiometric proportions of hydrogen sulfide and ammonia to a thermal oxidizer and an ammonia scrubber, respectively. To account for unmeasured or uncalculated sulfur feed to the thermal oxidizer, a feed back measurement of sulfur dioxide and ammonia concentration is used to correct the flow rate of hydrogen sulfide to the thermal oxidizer and/or ammonia to the ammonia scrubber.

A control system for an onboard oxygen generating system (OBOGS) includes a gain control communicatively coupled to an oxygen sensor configured to measure an oxygen concentration outputted from the OBOGS. The gain control selectively switches between unbalanced and balanced bed cycling modes of the OBOGS to produce a target oxygen concentration based on demand. A corresponding method includes providing a gain control communicatively coupled to an oxygen sensor configured to measure an oxygen concentration outputted from the OBOGS, controlling the OBOGS to operate in the unbalanced bed cycling mode when a low demand is placed on the OBOGS whereby the gain control provides a short bed cycle and a corresponding long cycle of a fixed cycle time, and switching the OBOGS to operate in the balanced bed cycling mode when a high demand is placed on the OBOGS. The balanced bed cycling mode operates at a decreased bed cycle time.

A control system for an onboard oxygen generating system (OBOGS) includes a gain control communicatively coupled to an oxygen sensor configured to measure an oxygen concentration outputted from the OBOGS. The gain control selectively switches between unbalanced and balanced bed cycling modes of the OBOGS to produce a target oxygen concentration based on demand. A corresponding method includes providing a gain control communicatively coupled to an oxygen sensor configured to measure an oxygen concentration outputted from the OBOGS, controlling the OBOGS to operate in the unbalanced bed cycling mode when a low demand is placed on the OBOGS whereby the gain control provides a short bed cycle and a corresponding long cycle of a fixed cycle time, and switching the OBOGS to operate in the balanced bed cycling mode when a high demand is placed on the OBOGS. The balanced bed cycling mode operates at a decreased bed cycle time.

Ionization systems and methods include moving air into contact with one or more ion generators and then past an ozone removal assembly to remove at least some ozone from the air. The air may be moved by a fan and may be filtered before contacting the one or more ion generators. The amount of one or more of the following of the air may be measured: the amount of ions, particulates, temperature, humidity, and other relevant factors. The ionization amount may be adjusted based on one or more of the measured amounts. The one or more ion generators and ozone removal assembly may be constructed as part of a single unit so they can be removed and replaced easily.

Ionization systems and methods include moving air into contact with one or more ion generators and then past an ozone removal assembly to remove at least some ozone from the air. The air may be moved by a fan and may be filtered before contacting the one or more ion generators. The amount of one or more of the following of the air may be measured: the amount of ions, particulates, temperature, humidity, and other relevant factors. The ionization amount may be adjusted based on one or more of the measured amounts. The one or more ion generators and ozone removal assembly may be constructed as part of a single unit so they can be removed and replaced easily.

Apparatuses and methods are provided for applying accelerated electrons to a gaseous medium by means of an electron beam generator, which has at least one cathode for emitting electrons and at least one electron exit window, wherein a) the at least one cathode is annular and the at least one electron exit window is in the form of an annular first hollow cylinder, the annular electron exit window in the form of the first hollow cylinder forms an inner wall of an annular housing of the electron beam generator, wherein the electrons emitted by the cathode are accelerated to the ring axis of the annular housing; b) an annular second hollow cylinder is arranged within the electron exit window in the form of the first hollow cylinder and delimits an annular space between the first hollow cylinder and the second hollow cylinder; c) a cooling gas is fed through the annular space between the first hollow cylinder and the second hollow cylinder; and d) the gaseous medium to which accelerated electrons are to be applied is fed through the second hollow cylinder.

A method for improving effectiveness of a steam generator system includes providing air to an air preheater in excess of that required for combustion of fuel and providing the air at a mass flow such that the air preheater has a cold end metal temperature that is no less than a water dew point temperature in the air preheater and such that the cold end metal temperature is less than a sulfuric acid dew point temperature. The method includes mitigating SO.sub.3 in the flue gas which is discharged directly from the air preheater to a particulate removal system and then directly into a flue gas desulfurization system. Flue gas reheat air is fed from the air preheater to heat the flue gas prior to entering a discharge stack to raise the temperature of the flue gas to mitigate visible plume exiting and to mitigate corrosion in the discharge stack.

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 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.