Odorant injection apparatus

An apparatus for odorizing LPG, comprising:

• (a) a pressurization means for supplying a pressurized gas;
• (b) tank for storing odorant under gas pressure directed from said pressurization means, said tank means having an interconnecting pipeline between said pressurization means and the top of said tank means to pressurize said odorant with said pressurized gas and provide an isolating blanket of said gas on top of said odorant, which limits the amount of odorant vented therefrom;
• (c) level pot means for measuring and holding a portion of odorant delivered thereto through a pipeline interconnecting said tank means to the bottom of said level pot means, said level pot means having an interconnecting pipeline between said pressurization means and the top of said level pot means to provide an isolating blanket of said gas on top of said odorant that limits the amount of odorant vented therefrom, further having an interconnecting pipeline from the top of said level pot means to a vent pipeline connected directly to a vapor return line, and having a pipeline interconnecting the bottom of said level pot means to a LPG loading pipeline;
• (d) first switch means for drawing a measured portion of said odorant from said tank means into said level pot means, which comprises:
• a first valve located in said pipeline between said tank means and said level pot means,
• a second valve located in said pipeline between the top of said level pot means and said vent pipeline,
• a first manually operated switching means connected to selectively direct gas flow from said pressurization means to operate a first pneumatic, valve actuator,
• a first four-way valve, which is actuated by said first pneumatic actuator, and which is connected to direct gas flow from said pressurization means, and
• a second pneumatic, valve actuator, which is connected to receive a gas flow directed from said first four-way valve and which is configured to simultaneously actuate said first and second valves to maintain said gas blanket in said level pot means during the filling thereof with odorant, thereby limiting the venting of odorant therefrom;
• and
• (e) second switch means for supplying said measured portion of odorant from said level pot means into said LPG loading pipeline, which comprises:
• a third valve located in said pipeline between said pressurization means and said level pot means,
• a fourth valve located in said pipeline between the bottom of said level pot means and said LPG loading pipeline,
• a second manually operated switching means connected to said pressurization means for flowing gas therefrom to operate a third pneumatic, valve actuator,
• a second four-way valve, which is actuated by said third pneumatic actuator and which is connected to direct gas flow from said pressurization means, and
• a fourth pneumatic, valve actuator, which is connected to receive a gas flow directed from said second four-way valve and which is configured to simultaneously actuate said third and fourth valves, thereby flowing odorant from said level pot means to said LPG loading pipeline.