Abstract: A method for preparing an adjustable organic fertilizer is provided. The method includes providing a ratio of nitrogen, phosphorus, and potassium required for a target crop and collecting a plurality of wastes. The method includes categorizing the fertilizer concentrations of the same type of feeding substrates within the wastes separately, and adjusting the composition of the categorized wastes to form a composite feeding substrate according to the ratio of nitrogen, phosphorus, and potassium required for the target crop. The method includes subjecting the composite feeding substrate to an anaerobic fermentation process. The anaerobic fermentation process includes introducing the composite feeding substrate into an acidification tank to obtain a first mixture and introducing the first mixture into a methanogenesis tank to obtain a second mixture.

Abstract: A biological wastewater processing system is provided, which includes a processing unit and a desulfurization bacteria culture tank. The processing unit is used to remove humic acid or color from wastewater. The processing unit includes a plurality of porous carriers, and the desulfurization bacteria and white-rot fungi are immobilized on the porous carriers. The desulfurization bacteria culture tank is used for cultivating the desulfurization bacteria, and the desulfurization bacteria culture tank is connected to the processing unit. In addition, the desulfurization bacteria culture tank produces a liquid containing sulfate ions, and the liquid containing sulfate ions is introduced into the processing unit to control the pH value of the processing unit, so that the pH value of the processing unit is between 5.5 and 6.5. A method for processing biological wastewater is also provided.

Abstract: A biological desulfurization processing system is provided. The biological desulfurization processing system includes a desulfurization reaction tank and a culture tank of desulfurization bacteria. The culture tank of desulfurization bacteria is used for cultivating desulfurization bacteria and is connected to the desulfurization reaction tank. The desulfurization reaction tank includes a desulfurization reaction zone. The desulfurization reaction zone includes at least one desulfurization layer and at least one supporting layer, and the desulfurization layer and the supporting layer are stacked in a staggered manner. A biological desulfurization processing method is also provided.