HiSIS High-speed Seabed Infiltration System Realizing a significant cost reduction for seawater desalination plants.

High-speed Seabed Infiltration System
Joint patent with Hitachi Zosen Corporation

The fact that of all the water on the Earth, just and only 3% is fresh water and the rest is seawater. In order to solve water shortage prevailing throughout the world, sea water desalination can be the only left solution for this global issue. The reality is that RO (reverse- osmosis), the dominant technology, can process at a rate of only 50% (at a maximum) of the whole amount of sea water intake. The larger the scale of the desalination plants become, the higher the initial cost goes up.
NAGAOKA has developed High-speed Seabed Infiltration System “HiSiS” jointly with Hitachi-Zosen, which is an innovative desalination technology with the application of NAGAOKA infiltration screen, reducing significant cost.

Comparison table
(case: intake amount of 100,000m3/day)

Technology HiSIS Conventional
seabed infiltration
Linear Velocity (LV) 100m/day 6m/day
Site area
1,000m2 Approximately
  • No marine
    organisms adhesion

  • Significant reduction
    in area of on-shore facilities

  • Reduction in dose
    of chemical

  • SWRO Flow
  • SWRO Flow(HiSIS) HiSIS significantly reduces pretreatment processes!
  • Comparison table
    Water intake method Direct intake HiSIS
    Marine organism adhesion 1-2 serious case(s) / year None
    Pretreatment drainage disposa Various facilities needed such as backwash waste tank, thickener, primary washer, secondary washer, dehydration None (Reduction in area of
    on-shore facilities)
    Chemical injection Large volume of sodium hypochlorite and coagulant are required Significant reduction in
    dose of chemicals.
    (No production of industrial disposal)

Reduction in initial costs and running costs

Pilot plant of HiSIS in the world

Umm Al Nar(Arabian Gulf/ Sas Al Nakhl Island),
June, 2014 ‒ March, 2016
Partnership with Hitachi Zosen for design, fabrication,
construction under the sponsorship of the Abu Dhabi Water and Electricity Authority(ADWEA)
400m3/day (LV 100m/d)
Caofeidian District, Tangshan-City, China
September, 2014 - September, 2016
Partnership with Beijing Enterprises Group Ltd.
for design, fabrication, and construction
4,400m3/day (LV 100m/d)