Liquid propane gas in bottles is used all over the world. When empty, the bottles are refilled. Siraga (Buzan Vais, France) designs and assembles filling installations for companies that fill bottles with liquid butane and propane. These installations may range from a simple filling apparatus to a large filling plant.
Gas bottles come in a wide variety of sizes, diameters and weights. The bottles also are returned in conditions ranging from virtually new to damaged or rusted. Some bottles are empty on return. Others are half full. The glass bottle valves and covers also differ according to the country where they're used.