Using the Earth to Clean Water ALCO CO., LTD. IP

Website: ALCO CO., LTD. (Japanese)external link
Category: Machinery

Making use of the microorganisms that live inside the soil around us, ALCO puts clean water within easy reach

Treating sewage and wastewater can be expensive and put a heavy load on natural resources. ALCO CO., LTD. harnesses the power of soil microbes to purify water for some of the country's best known parks and public spaces, using a method that is ecologically sound and economically viable.

Based in Mie Prefecture, ALCO has been building sewage and wastewater treatment tanks that combine a low environmental footprint with impressive filtration capabilities. As Kazuo Higashi, President and Representative Director of ALCO, explains, these tanks harness what are known as soil microbial membranes.


ALCO CO., LTD. President and Representative Director, Kazuo Higashi

SOFIL, the company's soil microbial membrane treatment product, comes into its strength after the primary treatment of the wastewater. The SOFIL tank is filled with a layer of permeable soil that contains microbes that remove a variety of polluting compounds.


The SOFIL wastewater treatment system – the primary treatment tank above, and the microbial membrane tank below, courtesy of ALCO CO., LTD

The Importance of Being Grounded

Thanks to the hardiness of the microbes, ALCO's method can offer several benefits. One is that it can be used in locations with seasonal or irregular usage. While the organisms used in water-based filtration methods might die out if the facility is not used regularly, SOFIL's microbes can survive during periods of dormancy and be quickly reactivated.

Because SOFIL only uses a very small fan powered by a minimal amount of electricity, the product can be kept running with power generated by a solar panel or a portable battery. And, despite its low power and maintenance requirements, using soil microbes for water filtration can reduce wastewater's biochemical oxygen demand, suspended solids, carcinogenic trihalomethanes, and water-bound estrogen at higher rates than activated sludge or biofilm methods. Thanks to their track record, Higashi explains, “we are the only water filtration via soil microbe method that is approved by the Ministry of Transportation. We are also the only company that is using the technique at this scale to clean water.”

SOFIL is being used around Japan at 170 different parks and other public spaces. Higashi adds with pride that it is being used at Okubo-ji, the final temple of the famous 88 Temple Pilgrimage in Shikoku, as well as the World Heritage Sites of Shirakami Sanchi (Shirakami Mountains) in Akita and Shimane's Iwami Ginzan (Iwami Silver Mine). “To be able to help keep the water beautiful at these World Heritage Sites is something that we are very proud of.”

A Pipeline for Future Plans

Currently, the soil used in SOFIL comes from four different places in Japan, and has been chosen for ideal permeability and microbe content. ALCO is now researching manmade soil in collaboration with Mie University, and they are testing it in Okinawa; at the same time, they have an updated soil microbial water treatment patent pending. ALCO has also teamed up with a solar panel provider and a construction company in order to create water treatment facilities with integrated power systems.

ALCO's first target for expansion is Asia: they are looking to find partners in Taiwan and they are engaged in research at Ho Chi Minh University in Vietnam. They hope to create manmade microbial soil for each new country they expand to, with a potential long-term goal of doing business in the United States or Europe.

Based on interview in January 2016


SOFIL is being used at the Shirakami Sanchi World Heritage Site in Akita Prefecture, courtesy of ALCO CO., LTD