On a conveyor firing machine, pellets are heated along the layer height in the heating and firing zone from top to bottom by gas – a heat carrier passing through the pellet layer and giving off part of the heat to heat the pellets. The temperature rise curve in the layer also changes – in the upper part, pellets are heated to 1280-1350 C, in the lower part to 1200 C. Different horizons of the layer along its height are processed with different temperature-time parameters. For example, pellets in the upper part of the layer are at a temperature of 1200 C for about 7-8 minutes, in the middle part of the layer for about 3-4 minutes, the presence of pellets in the lower part at the layer-bed boundary practically tends to zero time values. The strength characteristics of the pellets also change along the layer height. The strongest pellets are in the upper part of the layer, the least strong in the lower part of the layer. This is due to the low firing temperature in the lower part of the bed of about 1180-    1220 C and a short time interval between pellets being at these temperatures. To equalize the temperature characteristics along the bed height, it is necessary to keep the pellets in the lower part of the bed at the firing temperatures for a longer period of time and increase the filtration rate of the coolant in the bed. Temperatures in the furnace of the firing machine are monitored using thermocouples installed on the longitudinal walls of the furnace and determining the temperature of the coolant in the furnace or using pyrometric devices installed outside the furnace and directly determining the surface temperature of the pellet bed. The completion of the pellet firing process is monitored by the temperatures in the last vacuum chamber of the firing zone and the vacuum chamber of the recovery zone. The recommended temperature values in these vacuum chambers should be in the range of 450-600 C. In practice, when assessing the required temperature conditions in the furnace of the firing machine, the values of temperatures in the vacuum chambers, filtration rates and productivity of the firing machine, it is necessary to be guided by the requirements for the main quality characteristics of the roasted pellets shipped to the consumer - compressive strength (CSS), abrasion strength (AI), tumble strength (TI), strength at low-temperature recovery (LTD). When the specified values are met, the operation of the firing machine is optimized empirically, for example, by increasing the productivity of the firing machine or reducing the regulatory temperatures in the furnace of the firing zone or vacuum chambers.