TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Components: The device further comprises padding with desulfurizing bacterium filled in the inner chamber of the upper desulfurization tower and located under the spray head. The inner chamber of the upper desulfurization tower is further respectively provided with a hot water pipe coil, a marsh gas inlet pipe and a marsh gas distribution pipe arrayed under the padding from the top to bottom, and the marsh gas inlet pipe is connected with the marsh gas distribution pipe. The inlet end of the hot water pipe coil and the inlet end of the marsh gas inlet pipe hermetically pass through the side wall of the upper desulfurization tower and are located at the outer side of the upper desulfurization tower. The side wall of the upper desulfurization tower is provided with an upper single-substance sulfur discharge valve connected with the inner chamber of the upper desulfurization tower. The upper single-substance sulfur discharge valve is close to the bottom of the upper desulfurization tower. The inlet end of the liquid inlet pipe is hermetically connected with a nutrient liquid supplying tank at the outer side of the lower desulfurization tower. The outlet end of the liquid inlet pipe hermetically passes through the side wall of the lower desulfurization tower and located in the inner chamber of the lower desulfurization tower. The outlet end of the liquid inlet pipe is provided with a floating valve for controlling the connection of the liquid inlet pipe. A disc-shaped aerator with an aeration head is mounted in the lower desulfurization tower and the floating valve is located above the disc-shaped aerator. An air inlet pipe at the outer side of the lower desulfurization tower is connected with the aeration head of the disc-shaped aerator and provided with a gas inlet valve. The bottom of the lower desulfurization tower is provided with a lower single-substance sulfur discharge valve connected with the inner chamber of the lower desulfurization tower. The upper end of the reflux pipe is provided with a downwardly bent head connected with the bottom of the inner chamber of the upper desulfurization tower. The reflux pipe is provided with a balancing pipe for connecting the inner chamber of the reflux pipe with the outer atmosphere. An exhaust pipe is connected with the upper half part of the inner chamber of the lower desulfurization tower. A filter, a circulating pump and an adjusting valve are mounted on the conveying pipe based on the liquid flow direction in the conveying pipe and the inlet end of the conveying pipe is connected with the inner chamber of the lower desulfurization tower under the disc-shaped aerator. A discharge valve is mounted at the lower end of the filter. The upper and lower ends of the padding are respectively provided with a suit of data collector I containing a temperature sensor and a pH sensor. The inlet of the marsh gas inlet pipe is provided with a data collector II for detecting the hydrogen sulfide concentration and flow rate. The marsh gas outlet is provided with a gas concentration collector for detecting hydrogen sulfide concentration and oxygen concentration. The inner chamber of the lower desulfurization tower is provided with a data collector III for detecting the liquid temperature in the lower desulfurization tower, the pH value and the dissolved oxygen.