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Growth Strategies and Sustainability Management ︱3Feature

Our Technological Contribution to
Sewage Treatment Facilities

IntellectualCapital

Natural Capital

Sewage Treatment Mechanism and Sanki Engineering’s Major Technologies

Sludge collector withearthquake-proof mechanism
Equipment for scraping settled
sludgeSewageinflow

Sedimentation
basin

AEROWING
A diffuser that delivers oxygen to the reaction tank todecompose and purify contaminants, saving significant
energy by more efficiently transferring oxygen

Initial sedimentation
basin

Final sedimentation
basin

Aeration tank

SludgeTurbo-charged fluidized bed
incineration systemPiston pumpDehydrated sludge istransported via highpressure pipelines

Gravitational concentration

Mechanical concentration

SludgeDischarge

Disinfection

Feature 2 / Feature 3Sludge

Dyna Sand Filter
A sand filtration systemcapable of continuous
operation without clogging

Significantly reduces electricity consumption
by installing a turbocharger in the incinerator
that burns dehydrated sludge

Dehydration

Growth Strategies and Sustainability Management

Wastewater is an inevitable by-product of human society and industrial activity. The Sanki Engineering Group has helped enhance
comfortable living environments by providing advanced water treatment systems that combine wastewater purification and reusetechnologies. Sewage treatment facilities require enormous amounts of energy, and we recently observed strong demand for energy
conservation toward creating a sustainable society. In addition, as Japan’s population continues to fall, the declining volume of waterflowing into sewage treatment plants has posed the major challenge of downsizing to reduce treatment costs and scale. Sanki Engineering
is making a technological contribution to various stages of the sewage treatment process by fully leveraging the total engineering expertise
we have cultivated over the years.

Incinerator
SludgeAshSANDEC G3 decanter centrifuge
Research onconversion tofertilizer and feed

Separates sludge into water and solids. Its highcentrifugal force improves decanting performance
while reducing power consumption.

Case 1Case 2

Received an Order for Energy-Saving
Diffusers for a Large Sewage Treatment
Plant in Australia

Developed the Technology to Convert Sewage
Sludge into Feed and Fertilizer

In February 2023, AQUACONSULT, a Group company, received
an order for 5,700 energy-saving air diffusers used in the aeration
process* of sewage treatment at the Western Treatment Plant in
Melbourne, Australia, and the plant is scheduled to start operationsin the second half of 2024. It will treat 150,000 m3 of water per day,serving an equivalent of 750,000 people. The construction work
involves upgrading the huge lagoon, which stores 485,000 m3of water per day, by replacing it with reaction tanks equippedwith energy-saving diffusers. Furthermore, the diffusers will bearranged at closer proximity to enable the removal of organic
matter and nitrogen. The order
was awarded based on theproven life cycle cost, stableperformance, and energy
efficiency of the 1,700 diffusersthat have been in operation atthe plant since 2019.
*Provides oxygen to microorganisms that process organic matter andnitrogen contained in the water

Sewage sludge is invariably generated in the process of treating sewage,
and the conversion of sludge into feed and fertilizer has been attracting
attention. In March 2023, a joint research project by Akita Prefecture,
the Tokyo Metropolitan Government’s Bureau of Sewerage, and SankiEngineering on low-cost technology for converting sewage sludge
incineration ash into fertilizer was adopted as a feasibility study for theMinistry of Land, Infrastructure, Transport and Tourism’s Breakthrough by
Dynamic Approach in Sewage High Technology (B-DASH) Project. The
technology is expected to lower costs and save energy by using a simple
method for converting the incinerated ash of sewage sludge into granularfertilizer. In addition, in April 2023 our researchon the conversion of sewage sludge into feedand fertilizer using insects* was selected by
the ministry for its FY2023 Applied Researchon Sewage. This innovative technology is used
for feeding sewage sludge to immature insects
and converting the adult insects into feed andGranular fertilizer made fromtheir feces into fertilizer.
incinerated ash*Joint research by BioAlchemy Inc. and the Okinawa Institute of Science and Technology
SANKI REPORT 2023

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