A method of high pressure, high shear processing of a fluid, the method comprising the steps of: providing at least one isolator for selectively containing and discharging a second fluid, the at least one isolator further including an isolator wall defining a chamber , a separator positioned in the chamber and movable between a first end of the chamber and a second end of the chamber, the separator engaging the isolator wall to further divide the chamber into a first sub-chamber and a second sub-chamber that are in pressure communication with each other but are not in fluid communication with each other, a first sub-chamber inlet valve in fluid communication with an ultrahigh pressure pump and the first sub-chamber , a first sub-chamber outlet valve in fluid communication with the first sub-chamber , a first check valve in fluid communication with the second sub-chamber to allow fluid to enter the second sub-chamber , and a second check valve in fluid communication with the second sub-chamber to exhaust fluid from the second sub-chamber ; providing a processing unit in fluid communication with the second check valve of the at least one isolator ; alternately directing a first fluid at a pressure of at least 1.38 × 10 8 Pa (20,000 psi) into the first sub-chamber and directing the second fluid into the second sub-chamber , wherein directing the first fluid into the first sub-chamber causes the second fluid to be discharged from the second sub-chamber , through the second check valve , and through the processing unit ; and collecting the second fluid after it has passed through the processing unit . providing at least one isolator for selectively containing and discharging a second fluid, the at least one isolator further including an isolator wall defining a chamber , a separator positioned in the chamber and movable between a first end of the chamber and a second end of the chamber, the separator engaging the isolator wall to further divide the chamber into a first sub-chamber and a second sub-chamber that are in pressure communication with each other but are not in fluid communication with each other, a first sub-chamber inlet valve in fluid communication with an ultrahigh pressure pump and the first sub-chamber , a first sub-chamber outlet valve in fluid communication with the first sub-chamber , a first check valve in fluid communication with the second sub-chamber to allow fluid to enter the second sub-chamber , and a second check valve in fluid communication with the second sub-chamber to exhaust fluid from the second sub-chamber ; an isolator wall defining a chamber , a separator positioned in the chamber and movable between a first end of the chamber and a second end of the chamber, the separator engaging the isolator wall to further divide the chamber into a first sub-chamber and a second sub-chamber that are in pressure communication with each other but are not in fluid communication with each other, a first sub-chamber inlet valve in fluid communication with an ultrahigh pressure pump and the first sub-chamber , a first sub-chamber outlet valve in fluid communication with the first sub-chamber , a first check valve in fluid communication with the second sub-chamber to allow fluid to enter the second sub-chamber , and a second check valve in fluid communication with the second sub-chamber to exhaust fluid from the second sub-chamber ; providing a processing unit in fluid communication with the second check valve of the at least one isolator ; alternately directing a first fluid at a pressure of at least 1.38 × 10 8 Pa (20,000 psi) into the first sub-chamber and directing the second fluid into the second sub-chamber , wherein directing the first fluid into the first sub-chamber causes the second fluid to be discharged from the second sub-chamber , through the second check valve , and through the processing unit ; and collecting the second fluid after it has passed through the processing unit . <EOS>