NOVELTY - An in-vessel composting and digesting apparatus (100) comprises rotary drum fermenters (102); rectangular heater duct (104) to provide maximum heating surface area, and safety thermostat; heater pipe (108) coupling heater duct to each fermenter; supply blower for forcing air to enter each fermenter via heater duct; centrifugal blower (114) for sucking vapors and air outside the fermenter; thermocouples positioned at locations inside the apparatus; drive motor for driving fermenters; microwave guns coupled to fermenters via mechanical seal; and control panel.    USE - An in-vessel composting and digesting apparatus for organic material such as waste, particles and organic particles (claimed).    ADVANTAGE - The apparatus reduces pathogen contamination in organic material or fertilizer. Thus, yielding good quality of organic fertilizer; and providing smooth, safe, secure, continuous, and improved economical, convenient and energy efficient in-vessel thermophilic composting process.    DETAILED DESCRIPTION - In-vessel composting and digesting apparatus (100) comprises rotary drum fermenters (102); rectangular heater duct (104) having finned tube heaters arranged inside heater duct to provide maximum heating surface area, and safety thermostat; heater pipe (108) coupling heater duct to each fermenter, entering from a side of fermenter through mechanical seal, and extending horizontally inside the fermenter; supply blower for forcing air to enter each fermenter via heater duct; centrifugal blower (114) for sucking vapors and air outside the fermenter through exhaust pipes via mechanical seal; thermocouples positioned at locations inside the apparatus; drive motor for driving fermenters, and coupled to fermenters via gearbox and double chain system; microwave guns coupled to fermenters via mechanical seal; and control panel mounted on apparatus, and includes programmable logic controller, touch screen for providing automatic operation and monitoring of apparatus, and data logger for real time monitoring of temperature and time data. An INDEPENDENT CLAIM is included for a method of in-vessel composting and digesting organic material.    DESCRIPTION OF DRAWING(S) - The drawing is a perspective view of in-vessel composting and digesting apparatus.    In-vessel composting and digesting apparatus (100)    Rotary drum fermenters (102)    Rectangular heater duct (104)    Heater pipe (108)    Centrifugal blower (114)