Reduction of sludge in waste water drains Improvement of waste water processing,reduction of sludge and reduction of BOD loading
Here are examples of water quality improvement of waste water drains (reduction of BOD loading volume) and cost reduction of sludge processing by BW water reforming device.
Sludge by cleaning septic tank in housing reduced drastically from 80% full, and transparency of septic tank water increased rapidly
Building： Septic tank of general residence Location: Kouzu, Odawara city, Kanagawa prefecture
Occupation volume of activated sludge in septic tank was increased from 20% to 70~80% in three months before installation of BW device. The volume of sludge reduced drastically to 5 % after installation of BW water reforming device. Degree of transparency of water in septic tank was changed from 9.3 cm in average before installation of BW to 16 cm in average after installation of BW. Dissolved oxygen will activate aerobic microorganism which process and eat sludge. Amount of dissolved oxygen (DO value) was increased after BW installation.
Sludge in septic tank at Mr. N’s house Changes of SV value (Space Velocity value, sludge sediments ratio) and water transparency
Blue line : with BW installed Orange line: without BW 3 months/6 months/9 months after installation of BW
| Date measured | SV value(sludge sediments ratio）（％） | Transparency(cm) | DO（dissolved oxygen）(mg/l)※ |
|---|---|---|---|
| 平成11年11月10日 | 70 | 6 | 3.3 |
| 平成12年2月9日 | 20 | 11 | 4.0 |
| 平成12年5月6日 | 80 | 11 | 3.3 |
| 平成12年11月28日 BW設置 | |||
| 平成13年8月10日 | 5 | 18 | 6.1 |
| 平成13年11月12日 | 5 | 14 | 6.0 |
| 平成14年2月8日 | 5 | 16 | 6.0 |
Reduction of BOD load in waste water drains
Building: Ohtaki Co., Ltd. Wet towel cleaning factory
Location: Ibaragi plant
Test period: March 13, 2005 to June 13, 2005
Test method:
- BW water reforming device “The Biowater Ω８０” was installed in one of the two automated cleaning.
equipment lines at their wet towel cleaning factory. - Compare quality of finished products at the lines with and without BW water reforming device.
- We investigated the effect on waste water quality by supply water reformation, because waste water drains did not meet the specification (BOD 25) of waste water at Mitsukaido city.
Ohtaki Co., Ltd. Ibaragi factory Progress of BOD value of Waste water drains
25 is maximum limit of waste water specification at Mitsukaido city.
BOD value was drastically reduced in 3 months after installation of BW water reforming device.
Reduction of sludge processing cost by 67％
Building:Yokorei Co., Ltd.
Hitachi, Ltd. Storage System Division
How to estimate cost reduction of removal process of excess sludge
Building: Office building of Ricoh Engineering Co., Ltd. Location: Ebina office
Measurement: by Sougoukankyobunseki Co., Ltd.
| Water type | BOD value |
|---|---|
| Mixed water 1 to 1 ratio of BW reformed water and kitchen waste water | 20 |
| Mixed water 1 to 1 ratio of non-reformed water and kitchen waste water | 70 |
With diluted BW reformed water, waste water had reduction of BOD by 20%.
With this test, waste water was diluted by 50%. In actual case, entire waste water is reformed by BW device, and therefore 40% reduction of BOD value is possible. Also, 40% cost reduction is possible as processing cost.