The document discusses the MASTER System for optimizing the use of alternative fuels in cement plants. The system includes new grinding equipment, a drying step, and new burning equipment to increase the substitution rate of solid alternative fuels to 100%. It is a combination of the Rocket Mill for grinding and drying fuels and the Flexiflame EcoPro rotary kiln burner. The MASTER System significantly increases the total substitution rate and allows for 100% substitution of solid alternative fuels, providing advantages like increased fuel substitution rates, higher efficiency, and reduced CO2 emissions and fuel costs.