DHW WATER HEATING PIPING DESIGN

Need to run 500 feet ( 250 supply, 250 ft return) of DHW heating copper pipe ( 2 inch) from a 140 KW ( 500,000 BTU) heat pump to a 500 gallon storage tank and need to determine
(1) pump size ( suggest HP)
(2) verify if 2 inch is adequate
(3) type of piping to use ( suggest using 2 inch copper,"L", victaulic quick connect )