| Project/Area Number |
12558073
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 展開研究 |
|---|
| Research Field |
環境保全
|
|---|
| Research Institution | Toyama National College of Technology |
|---|
Principal Investigator |
IWAI Masao Professor, Department of Ecomaterials Engineering, 環境材料工学科, 教授 (80042828)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
OHTSUKI Chikara Associate professor, Graduate School of Materials Science, Nara Institute of Science and Technology, 物質創成科学研究科, 助教授 (00243048)
TAFU Masamoto Research Associate, Department of Ecomaterials Engineering, 環境材料工学科, 助手 (50270244)
CHOHJI Tetsuji Professor, Department of Ecomaterials Engineering, 環境材料工学科, 教授 (80092790)
|
|---|
| Project Period (FY) |
2000 – 2002
|
| Project Status |
Completed (Fiscal Year 2002)
|
| Budget Amount *help |
¥6,500,000 (Direct Cost: ¥6,500,000)
Fiscal Year 2002: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 2001: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 2000: ¥3,700,000 (Direct Cost: ¥3,700,000)
|
|---|
| Keywords | Phosphate / Fluoride / Apatite / Waste from Marine Industries / Calcium Phosphate / Resource Recovery / 資源化 |
|---|
| Research Abstract |
(1) Recovery of phosphate : The kinetics of the oxidation of phosphorous acid solution with oxygen in the presence of Cu (II) was studied. The achievement of oxidation above 90% is readily done at 373K, 3 atm, pH 3, [Cu (II)] 1.0Χ10^<-3>moldm^<-3> during the retention time of 200 minutes. It was considered that autoxidation reaction may be applicable to the recovery of phosphate in spent electroless plating liquors.
(2) Fluoride removal from industrial wastewater : It is found that CO_2 in the atmosphere interferes with fluoride removal efficiency and produces a large amount of sludge by forming calcium carbonate. In order to confirm these phenomena, experiments using real wastewater under normal and degassed conditions were carried out not only by measuring the fluoride concentration in the wastewater, but also by characterizing the properties of the formed sludge. As a result, the calcium fluoride method under degassed conditions is suggested to be a very promising method for treatment of wastewater containing fluoride from the viewpoint of minimum emission.
(3) Development of fluoride recovery system : A novel system of fluoride removal from wastewater was assessed from the viewpoint of "Ecotechnology". The equipment with activated alumina in a column can remove fluoride without increment of any chemical components in treated water. However, this system must be regenerated after activated alumina saturating, in order to minimize the emission derived from it. Then, we proposed an ecotechnological fluoride treatment system, which is composed to combine the adsorption and co-precipitation with aluminum hydroxide, and fluoride was removed as calcium fluoride from the system. As a result, the system is suggested to be very promising because of it's possibility of energy saving and resources saving.
|
