Abstract
The authors have been developing the establishment method of a phosphate ion removal, recovery and recycling system using a synthesized Mg-Al-Cl form hydrotalcite (HT).The powder form of HT, however, was not ideal for wastewater treatment because of its poor solid-liquid separating efficiency; thus, the authors have developed a HT-carrying fiber (HTCF). We have investigated practical ability by measuring the removal adsorption rate and breakthrough capacity of the HTCF for phosphate ions by a column method using a sample phosphate solution and secondary treated wastewater from a rural sewerage facility. It was found that, the breakthrough capacities of the HTCF were in the range of 28.72-30.68 mg-P·g-1 in the case of using the sample phosphate solution, and in the range of 15.32-16.27 mg-P·g-1 in the case of the secondary treated wastewater with the range of space velocities being from 1.5 to 6.0·h-1. It was suggested that the decreased breakthrough capacities of the HTCF in the case of using the secondary treated wastewater were attributed mainly to HCO3- ions contained in the wastewater. However, the removal ability of the HTCF for phosphate ions in using actual secondary treated wastewater is sufficient, that is to say, it seems that the developed HTCF is a promising practical removal adsorbent for phosphate ions in wastewater.
