In　this　paper,　two　configurations　of　Kalina-Flash　cycles　(KFC)　are　proposed　to　recover　low-grade　heat　source.　The　thermodynamic　and　economic　models　of　Kalina-Flash　cycles　are　established.　A　numerical　simulation　is　conducted,　and　a　parametric　analysis　is　performed　to　examine　the　effect　of　five　key　parameters,　including　separator　temperature,　separator　pressure,　ammonia　mass　fraction　of　ammonia-water　basic　solution,　flash　pressure　and　pinch-point　temperature　difference,　on　the　thermodynamic　and　economic　performances　of　Kalina-Flash　cycles.　Furthermore,　a　single-objective　optimization　and　a　multi　objective　optimization　are　carried　out　by　genetic　algorithm　and　Non-dominated　sorting　genetic　algorithm-II　to　obtain　the　optimum　thermodynamic　and　economic　performances.　The　single-objective　optimization　results　show　that　the　Kalina-Flash　cycles　can　achieve　higher　exergy　efficiency　and　lower　specific　investment　cost　than　Kalina　cycle　does.　The　multi-objective　optimization　results　of　Kalina-Flash　cycles　present　the　Pareto　frontier　solutions,　which　is　a　series　of　optimum　solutions　for　exergy　efficiency　and　total　capital　investment.　The　Pareto　frontier　solutions　indicate　that　Kalina-Flash　cycles　are　superior　to　Kalina　cycle　in　the　aspect　of　thermodynamic　and　economic　performances.　(C)　2017　Elsevier　Ltd.　All　rights　reserved.