Fujita Corporation Innovative Products

Earth Air Purification

Civil Marker

Unmanned Construction

As traffic volumes increase, so urban air quaility deteriorates - particularly along main roads and highways, and at busy intersections. Although the long-term solution is reduction of traffic levels through improved public transportation, in the short term the most pressing need is to reduce levels of atmospheric pollutants. In this case, Fujita's Earth Air Purifiers (EAPs) provide a new and innovative solution.

Fujita's Earth Air Purifier Systems

EAPs are an environmentally-friendly way of improving urban air quality by taking advantage of naturally-occuring biological and biochemical processes. EAPs pump polluted air into a wind tunnel under specially-designed 'gardens'. As the air passes through the soil (and through the root-zone of the plants in the bed) physical, biochemical and biological processes combine to remove pollutants from the air stream.

EAP schematic

EAPs are suitable for installation in many urban environments, including at busy road intersections, above underground car parks and road tunnels, and at airports. In addition to improvements in local air quality, such installations also replace urban 'dead space' with visually-attractive greenery.

The performance of our EAPs have so far been very encouraging. On an annual basis Fujita's eight Japanese pilot plants have been shown to remove more than 80% of nitrogen oxides from polluted air. They also remove more than 90% of carbon monoxide, sulfur dioxide and suspended particulate matter, and more than 75% of non-methyl hydrocarbons.

Recent EAP installations

Project	Type	Area (m²)	Purified Air (m³/h)
Type U= underground parking lot; Type R= roadside installation; Type T= road tunnel HVAC
1. Adachi Ward	U	110	8,000
2. Ashiya City	U	80	5,760
3. Seishin City	U	200	14,400
4. Suita City	R	500	36,000
5. Hanna Tunnel	T	400	28,800
6. Itabashi Ward	R	40	2,800
7. Kawasaki City	R	500	72,000
8. Fujisawa City	R	280	20,600
9. Itabashi Ward	R	700	100,000

The success of Fujita's EAP technology in the field was not unexpected. Prior to deployment of EAP pilot plants, rigorous testing was carried out at Fujita's Technical Institute.

laboratory testing

The diameter of the plexiglass columns are 18 cm and thickness of the soil layer is 50cm (the same depth as used in the field). Artificially polluted air passes through the soil layer, from the bottom to the surface at the speed of 10-30mm/sec and total flow volume is 60-180 l/min.

The figure below shows the monitoring apparatus used in the laboratory testing of the EAP process and in assessing the effectiveness of different soil mixes.

Schematic of laboratory system

Click the icon to download our EAP brochure in Adobe® Acrobat® format. For further information contact Dr. Sam Kadota