NOVELTY - A wastewater treatment equipment (1A) has a sulfuric acid reductive reaction tank (2) in which anaerobic processing of wastewater as process target is carried out to produce hydrogen sulfide, decomposition of organic substance is carried out with injection of sulfate reducer, and reduction of sulfate ion is carried out with injection of methane producer, a methane fermentation tank (3) in which anaerobic processing is carried out to decompose organic substance in processed wastewater discharged from sulfuric acid reductive reaction tank, and biological desulfurization processing tank (4).    USE - Equipment is used for treating wastewater (claimed) e.g. industrial wastewater and sewage.    ADVANTAGE - The equipment efficiently removes organic substance from the wastewater.    DETAILED DESCRIPTION - A wastewater treatment equipment has a sulfuric acid reductive reaction tank in which anaerobic processing of wastewater as process target is carried out to produce hydrogen sulfide, decomposition of organic substance is carried out with injection of sulfate reducer, and reduction of sulfate ion is carried out with injection of methane producer, a methane fermentation tank in which anaerobic processing is carried out to decompose organic substance in processed wastewater discharged from sulfuric acid reductive reaction tank, and biological desulfurization processing tank in which sulfuric acid is produced using hydrogen sulfide generated by sulfuric acid reductive reaction tank and carrying out desulfurization by Acidithiobacillus, and the generated sulfuric acid is supplied to sulfuric acid reductive reaction tank for reduction of sulfate ion. An INDEPENDENT CLAIM is included for wastewater treatment method.    DESCRIPTION OF DRAWING(S) - The drawing shows the schematic view of the wastewater treatment equipment. (Drawing includes non-English language text)    Wastewater treatment equipment (1A)    Sulfuric acid reductive reaction tank (2)    Methane fermentation tank (3)    Biological desulfurization processing tank (4)    Pipes (11-19)