Worthington Cylinders

Darling International Inc. is one of the nation's leading providers of rendering, recycling and recovery solutions to the food industry. Based in Wichita, Kan., the company offers an array of services, such as blending, clean star, trap cleaning and rendering, to name a few. It also provides a series of restaurant services, including used-cooking oil removal, used-oil storage systems and grease trap service. Additionally, Darling International Inc. offers a variety of animal protein meals, hides, fats, oils and many more.

Frontier El Dorado Refining is a subsidiary of Frontier Oil Corporation. The company produces gasoline, diesel fuels, aviation fuels and asphalt. It is one of the largest refineries in Kansas. Frontier El Dorado Refining has the capability to process approximately 110,000 barrels of crude oil and nearly 15,000 barrels of natural gas liquids daily. Frontier Oil Corporation is an independent oil refining and marketing company. It has refineries in Wyoming and Kansas. Its primary products of gasoline, diesel and asphalt are marketed in the Rocky Mountain and Plains States. Frontier Oil Corporation sells most of its gasoline and diesel to unbranded jobbers, but also has supply arrangements to retail operations of other oil companies, such as CITGO Petroleum. Frontier El Dorado Refining is located in El Dorado, Kan.