NOVELTY - Apparatus for use in scavenging hydrogen sulfide from sour natural gas under pressure at a well or battery site to produce sweetened gas, comprises a contactor pressure vessel (2) forming an internal reaction chamber (5) for containing continuously replenished triazine; a porous, permeable body (23) of inert material; heater (26) for externally heating the contactor vessel; and a gravity separation vessel (3) forming an internal separation chamber (6), and having outlet for separately removing and recovering separated sweetened gas and spent triazine from the separation chamber.    USE - In scavenging hydrogen sulfide from sour natural gas under pressure at a well or battery site to produce sweetened gas.    ADVANTAGE - The system is capable of treating sour natural gas at a well or battery site so that sufficient sweet or fuel gas may be produced to operate ancillary equipment at the site. The system equipment is compact so that it is easily and readily transportable to and from the site. The system enables the natural gas producer to use some of the gas produced from a well to operate on-site equipment. The system sweeten enough sour gas to supply fuel gas at a pressure sufficient to operate ancillary equipment at the site, thus supplanting the use of propane.    DETAILED DESCRIPTION - Apparatus for use in scavenging hydrogen sulfide from sour natural gas under pressure at a well or battery site to produce sweetened gas, comprises a contactor pressure vessel (2) forming an internal reaction chamber (5) for containing continuously replenished triazine, the vessel having first inlet, communicating with the reaction chamber at one end, for supplying and distributing triazine and sour natural gas across the reaction chamber, the vessel having outlet, communicating with the reaction chamber at its other end, for removing sweetened gas and spent triazine; a porous, permeable body (23) of inert material providing a contact surface for dispersing sour gas in triazine for scavenging interaction, the body extending across the reaction chamber between the inlet and outlet; heater (26) associated with the contactor vessel, for externally heating the contactor vessel; and a gravity separation vessel (3) forming an internal separation chamber (6) and having second inlet connected with the contactor vessel outlet for receiving the sweetened gas and spent triazine, the separation vessel having second outlet for separately removing and recovering separated sweetened gas and spent triazine from the separation chamber. An INDEPENDENT CLAIM is included for method for scavenging hydrogen sulfide from a pressurized side stream of sour natural gas at a well or battery site, involving continuously introducing and distributing a mixture of sour natural gas and neat triazine across the cross sectional area of a columnar reaction chamber at the chamber's lower end; dispersing the mixture over a reactant contact area provided by a mass of interconnected strands, where the triazine scavenges sulfides from the sour natural gas to produce sweetened natural gas and spent triazine; removing spent triazine and sweetened natural gas from the reaction chamber; separating the spent triazine and sweetened natural gas by gravity separation in a separation chamber; separately recovering spent triazine and sweetened natural gas streams from the separation chamber; and using the recovered sweetened natural gas to operate ancillary equipment at the site.    DESCRIPTION OF DRAWING(S) - The figure shows current flow sheet.    Contactor pressure vessel (2)    Gravity separation vessel (3)    Internal reaction chamber (5)    Internal separation chamber (6)    porous permeable body (23)    Heater (26)