Calumet Specialty Products Partners LP announced its investment Monday as a joint venture partner in the construction of a $135 million commercial gas-to-liquids plant in Lake Charles.

The plant is expected to be operational by late 2015. It will produce from natural gas 1,100 barrels per day of refined products, including waxes, drilling fluids, distillate and naphtha.

The plant will be owned and operated by Juniper GTL LLC , a company also co-owned by SGC Energia and Great Northern Project Development.

It will be funded through a combination of equity and senior secured debt. Calumet, a major producer of specialty hydrocarbon and fuel products, intends to invest $25 million in exchange for an equity interest of about 22 percent in the joint venture.

“This joint venture offers Calumet the opportunity to lead a growing market that converts lower-cost natural gas into higher value liquids,” said Jennifer Straumins, president and chief operating officer of Calumet.

Calumet is based in Indianapolis, Indiana, and has 13 facilities located in northwest Louisiana, northwest Wisconsin, northern Montana, western Pennsylvania, Texas, New Jersey and Oklahoma.