Hydroentanglement
Specific energy is the process variable, not pressure. Same bar, half the belt speed, twice the entanglement.
— kJ/kg
Hydraulic energy delivered per kilogram of web
Water circulated is not water consumed — a spunlace line recirculates through filtration, and make-up water is a small fraction of this figure. Size the filtration plant on the circulated flow.
Spunlace Water Pressure, Flow & Specific Energy Calculator — free, with the formula and a worked example, at Textile School.