화학공학소재연구정보센터
Chemical Engineering and Processing, Vol.107, 157-167, 2016
Alternatives of integrated processes for coproduction of LNG and NGLs recovery
In this paper, integrated schemes for production of LNG and NGLs recovery are presented and DMR liquefaction cycle serves as a base process to which separation process of NGLs is integrated at. Main highlight of integration is a split of demethanizer into rectifying and stripping sections whereby light components of liquid stream from natural gas flashed throughout phase separator are stripped via stripping column while vapor stream is rectified into rectifier. To reach operating pressure of demethanizer requires to reduce pressure of flashed natural gas which gives an option of reusing the released power to recompress lean methane from NGLs recovery process. As for heat integration, rectifier is operated at low temperature and direct heat integration between both sections of demethanizer is not likely; thus heat of the final products in NGLs recovery train is retrieved by interreboiling stripping section. After all integration, mixed refrigerant cycle is optimized for compression energy requirement by varying the refrigerant composition and operating pressure levels through knowledge-based optimization methodology. The integrated schemes minimize the overall energy requirements. (C) 2016 Elsevier B.V. All rights reserved.