Abstract: An improved contaminant abatement process is disclosed which provides effective, cost efficient abatement of contaminants, and particularly hydrogen sulfide and sulfide ions, from geothermal power plant effluents. The process of the present invention is suitable for use with geothermal power plant effluent treatment systems having a primary hydrogen sulfide abatement system for removal of hydrogen sulfide from noncondensable gases, and a secondary hydrogen sulfide abatement system for removal of hydrogen sulfide from condensate. At least a portion of the condensate separated in the primary condenser is diverted for reinjection to the geothermal well prior to treatment in the secondary hydrogen sulfide abatement system. Diversion of at least a portion of the condensate comprising substantial amounts of hydrogen sulfide and sulfide ions reduces the cost of secondary hydrogen sulfide abatement, and reduces the costs involved in abatement of other contaminants.

Abstract: A lighting system for illuminating a given area is disclosed herein and includes a number of luminaires, each having a light source and a light sensitive device for automatically connecting the light source to a supply of power during the dark hours of the night and for automatically disconnecting the light source during the light hours of the day. This system also includes light control circuits associated with some but preferably not all of the luminaires. Each light control circuit overrides the operation of an associated light sensitive device and automatically disconnects its light source from the power supply for a predetermined period during the dark hours at a time when it is not important to provide a high degree of illumination, for example in the middle of the night.