Abstract: Disclosed in the present disclosure is a double-deck multi-span bridge construction method. According to the double-deck bridge construction method of the present disclosure, construction is carried out by using a method of disassembling a support jig frame in a graded and span-separated mode, an upper chord jig frame and a lower chord jig frame can be used in a recycle manner, and construction costs are reduced. In addition, a construction period of building the support jig frame is shortened, and other construction operations can be synchronously carried out on a span in which the jig frame is disassembled, for example, fire retardant coating construction can be carried out on a mounted bridge deck after the jig frame is disassembled, and the construction period of a double-deck multi-span bridge is effectively shortened.

Abstract: A method for effectively removing acidic sulfide gas using ammonia-based desulfurization includes the following steps of: 1) pre-treatment, wherein sulfide in acid gas undergoes through pre-treatment methods of sulfur recovery, acid making or/and incineration to convert remaining sulfur in the acid gas into sulfur oxides, and the acid tail gas with sulfur oxides is obtained; and the acid gas is derived from petrochemical industry, natural gas chemical industry, coal chemical industry, etc.; 2) ammonia absorption of sulfur oxides, wherein the acid tail gas with sulfur oxides is allowed to flow into an ammonia absorption apparatus, and a cyclic absorption solution is used to absorb sulfur oxides; and 3) post-treatment of ammonium sulfate, wherein a saturated or nearly saturated absorption solution undergoes concentration, crystallization, solid-liquid separation, and drying to obtain a solid product of ammonium sulfate.