NOVELTY - The method for biologically treating petroleum-contaminated waste/wastewater, comprises introducing a kenaf core powder into the waste/wastewater, processing the petroleum-contaminated waste/wastewater and kenaf in a bio-reactor (13) and a clarifier (14), and dewatering the petroleum-contaminated waste/wastewater and kenaf mixture to produce a bio-solid material. The kenaf powder is introduced into the petroleum-contaminated waste/wastewater at a rate of 100-5000 mg/l. After the dewatering process, the bio-solid material is dried to produce a biomass fuel.    USE - The method is useful for biologically treating petroleum-contaminated waste/wastewater by petroleum refining and/or petrochemical industry, while simultaneously producing a high energy solid fuel that is useful in industrial cement plants and/or power plants.    ADVANTAGE - The method is capable of treating and converting the hazardous waste to non-hazardous waste, can able to produce a viable solid fuel product instead of a waste, and requires less operating cost.    DETAILED DESCRIPTION - The method for biologically treating petroleum-contaminated waste/wastewater, comprises introducing a kenaf core powder into the waste/wastewater, processing the petroleum-contaminated waste/wastewater and kenaf in a bio-reactor (13) and a clarifier (14), and dewatering the petroleum-contaminated waste/wastewater and kenaf mixture to produce a bio-solid material. The kenaf powder is introduced into the petroleum-contaminated waste/wastewater at a rate of 100-5000 mg/l. After the dewatering process, the bio-solid material is dried to produce a biomass fuel. The method further comprises a clarifier step prior to directing settled clarifier solids to the bio-solid dewatering step. An INDEPENDENT CLAIM is included for a method of producing a biomass fuel.    DESCRIPTION OF DRAWING(S) - The drawing shows a process flow diagram illustrating the method for treating petroleum-contaminated waste/wastewater.    Influent waste/wastewater stream (11)    Kenaf feed system (12)    Bio-reactor (13)    Clarifier (14)    Dewatering solids (17)    Drying solids (21)    Biomass fuel. (22)