An　integration　system　for　1000　MW　S-CO2　connected-top-bottom　power　cycle　with　overlap　utilization　and　coal-fired　boiler　is　developed.　The　adaptive　modification　module　is　introduced　to　eliminate　the　non-convergence　for　S-CO2　superheater　thermal　calculation　in　the　system　iteration.　Thermal-hydraulic　performance　in　terms　of　thermal　performance,　cycle　efficiency,　heater　configurations,　heater　areas　and　final　parameter　evenness　are　discussed.　Firstly,　the　strong　constraint　effects　of　inlet　and　outlet　parameters　on　superheater　thermal　calculation　convergence　are　demonstrated　and　the　adaptive　modification　module　is　established.　Secondly,　based　on　the　detailed　thermal-hydraulic　analysis,　different　layouts　are　compared　to　identify　the　flow　path　way　and　the　heat　absorption　of　S-CO2　flow　in　different　heating　processes.　The　midpoint　between　the　two　peaks　of　heat　flux　is　recommended　as　the　start　point　for　the　cold　fluid　placement　in　cooling　wall　arrangement.　Finally,　a　new　layout　is　proposed　to　obtain　the　highest　overall　thermal-hydraulic　performance,　with　a　net　power　efficiency　up　to　47.57%　and　a　total　heater　area　of　316426.18　m2.　The　design　sequences　for　S-CO2　coal-fired　boiler　heaters　are　recommended　as　well.　©　2020　Elsevier　Ltd