This product belongs to the field of agricultural machinery technology and is mainly used for mechanical acid regulation of soil automatic irrigation. The product is mainly composed of a feeding box, a combustion chamber, a sprinkler, a water-gas reaction buffer chamber, and a centrifugal pump. The feeding box is connected to the combustion chamber through a lower feeding channel. The top of the combustion chamber is equipped with an air duct, and a sprinkler is installed on the air duct. The sprinkler is connected to the inlet pipe of the irrigation main pipeline and is connected to the water-gas reaction buffer chamber through a conduit. The water-gas reaction buffer chamber is connected to the centrifugal pump through a pipeline, and the top of the water-gas reaction buffer chamber is equipped with a flue. The outlet of the centrifugal pump is connected to the outlet pipe of the irrigation main pipeline.