Abstract: Cotton waste is transferred to a heated reactor and mixed with a pigment in the presence of steam. Cotton waste is converted to mulch by a plurality of rotating mixing elements disposed in the reactor and which mix, cut and/or chop the cotton waste therein. In particular, the reactor includes a cylindrical wall section and a longitudinal drive shaft extending through the reactor. A series of radial arms extend from the drive shaft. Mounted on the terminal ends of the radial arms is a first set of mixing elements. As the drive shaft is driven, these mixing elements move adjacent the inner surface of the cylindrical wall section. Further, there is provided a second set of mixing elements disposed adjacent the inner face of the cylindrical wall section. These rotary mixing elements are secured to a shaft that extends through the cylindrical wall section at an angle to the longitudinal drive shaft.