System and method for co-producing low carbon olefin and ammonia by low carbon alkane

Abstract

The invention relates to a system and method for co-producing low carbon olefin and ammonia by low carbon alkane. The system comprises an alkane dehydrogenation device (100), an air separation unit (200) and an ammonia synthesis device (300). The alkane dehydrogenation device (100) is connected with the ammonia synthesis device (300) by a hydrogen conveying pipeline (12). The air separation unit (200) is connected with the ammonia synthesis device (300) by a nitrogen conveying pipeline (22). The low carbon alkane is reacted in the alkane dehydrogenation device so as to obtain the corresponding low carbon olefin and hydrogen, a low carbon olefin product with high purity and the hydrogen are obtained by the separation, the hydrogen is conveyed into the ammonia synthesis device, and reacts with the high-purity nitrogen obtained by the air separation unit, so the ammonia is generated. Compared with the current olefin uni-yield alkane dehydrogenation technology or coal-based synthesis ammonia technology, the method is capable of adequately using the byproduct hydrogen in the alkane dehydrogenation process to generate the ammonia, and has the advantages of short technological process, less waste discharge, and high economic and social benefit.

Description

technical field [0001] The invention belongs to the field of chemical industry, and in particular relates to a system and method for co-producing low-carbon olefins and ammonia from low-carbon alkanes. Background technique [0002] Olefins, especially low-carbon olefins, ethylene, propylene and butene (including n-butene, 2-butene and isobutene) are the basis of the entire petrochemical industry, and their output and technical level represent the country's economic and technological development level. At present, low-carbon olefins mainly come from petroleum cracking (including steam cracking and catalytic cracking). The emerging coal chemical route, that is, methanol to olefins (MTO, MTP) is mainly suitable for countries and regions rich in coal resources, because methanol can be produced with cheap coal, and it is currently developing rapidly in my country. In addition, with the exploitation of natural gas in the United States and the Middle East, especially shale gas, a ...

AI Technical Summary

Problems solved by technology

At present, my country's ammonia synthesis route mainly adopts the coal gasification route with coal as raw material, which requires large investment, high energy consumption, and pollution of waste gas, waste residue and waste water.

Images