Removal of phosphorus from wastewater by activated alumina adsorbent

1997 ◽  
Vol 35 (7) ◽  
pp. 39-46 ◽  
Author(s):  
Tadashi Hano ◽  
Hirokazu Takanashi ◽  
Makoto Hirata ◽  
Kohei Urano ◽  
Shunji Eto

The adsorption characteristics of activated alumina treated with aluminum sulfate were studied to develop a new removal process for low concentration phosphorus in the waters of rivers and lakes. The equilibrium study showed that the adsorption capacity was enhanced about 1.7-fold by treating with aluminum sulfate. The effective intraparticle diffusion coefficients, determined by the Boyd's method based on batch runs, were hardly affected by such a low phosphorus concentration as observed in the water of rivers and lakes under investigation. The temperature dependence of the intraparticle diffusion coefficients based on the concentration in solid showed the activation energy of 29.7kJ·mol−1, which was a little higher than that in usual pore diffusion. The maximum continuous operation term (regeneration cycle) of the present phosphorus adsorption system was estimated. Under the conditions of influent phosphorus concentration of 0.1 g·m−3, removal extent of 90%, particle size of 2 × 10−3m, temperature of 298K and space velocity of 1.39 × 10−3s−1 (5h−1), the present removal system remained effective for about 500 days.

2010 ◽  
Vol 152-153 ◽  
pp. 945-949
Author(s):  
Chun Sheng Ding ◽  
Ying Long Zou ◽  
Fang Ming Ni ◽  
Qian Fen Zhu

In the study, activated alumina was modified by calcium chloride, and after modification the phosphorus removal from aqueous solution increased by 13% or so. Then the activated alumina with and without treatment were subjected to characterization by the methods of the BET and SEM, and the adsorption characteristics of modified activated alumina were further studied at different contact time, pH values, adsorbent dosage levels and initial phosphorus concentration. Moreover, the equilibrium adsorption data for phosphorus were better fitted to Langmuir adsorption isotherm, and it means that the uptake of phosphorus preferably followed the monolayer adsorption process.


2015 ◽  
Vol 71 (7) ◽  
pp. 996-1003 ◽  
Author(s):  
Yupan Yun ◽  
Xiaoqin Zhou ◽  
Zifu Li ◽  
Sayed Mohammad Nazim Uddin ◽  
Xiaofeng Bai

This research mainly focused on the phosphorus removal performance of pilot-scale vertical flow constructed wetlands with steel slag (SS) and modified steel slag (MSS). First, bench-scale experiments were conducted to evaluate the phosphorus adsorption capacity. Results showed that the Langmuir model could better describe the adsorption characteristics of the two materials; the maximum adsorption of MSS reached 12.7 mg/g, increasing by 34% compared to SS (9.5 mg/g). Moreover, pilot-scale constructed wetlands with SS and MSS were set up outdoors. Then, the influence of hydraulic retention time (HRT) and phosphorus concentration in phosphorus removal for two wetlands were investigated. Results revealed that better performance of the two systems could be achieved with an HRT of 2 d and phosphorus concentration in the range of 3–4.5 mg/L; the system with MSS had a better removal efficiency than the one with SS in the same control operation. Finally, the study implied that MSS could be used as a promising substrate for wetlands to treat wastewater with a high phosphorus concentration. However, considering energy consumption, SS could be regarded as a better alternative for substrate when treating sewage with a low phosphorus concentration.


1998 ◽  
Vol 38 (1) ◽  
pp. 55-62 ◽  
Author(s):  
S. C. Williams ◽  
J. Beresford

Thames Water have built a three-stage Bardenpho activated sludge plant to treat 50% of the wastewater flow at Slough in the United Kingdom. Following commissioning, the plant performed well in terms of nitrification and denitrification but did not produce an effluent with a low phosphorus concentration. One possible explanation for the poor performance was the mixing of the anaerobic zone. The flow characteristic of the anaerobic zone was identified by tracer tests and alternative mixing regimes were tested. The results showed that reducing the mixing energy in the anaerobic zone had no detrimental effect on the effluent quality. The plant has operated with the reduced mixing input for nine months and the effluent phosphorus concentration has been reduced from 2.1 mgl−1 to 0.8 mgl−1.


BioResources ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. 1335-1357
Author(s):  
Qing Zhang ◽  
Yan-mei Ding ◽  
Lin Lu ◽  
Jing-xi Li ◽  
Mei-na Liang ◽  
...  

This study combined chemical ultrasonic modifications and microwave oven heating to prepare a novel adsorbent, bagasse iron oxide biochar, (BIBC) to remove phosphate from aqueous solutions. The characterization of BIBC was made by energy dispersive spectrometry (EDS), Brunauer–Emmett–Teller (BET), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses, and the mechanism of phosphorus adsorption on BIBC was researched by adsorption batch experiments with emphasis on pH, dosages of BIBC, initial phosphorus concentration, and adsorption time. The BIBC’s BET specific surface area and pore volumes were 81.94 m2 g−1 and 26.74 cm3 g−1, respectively. The pH for the optimal phosphorus adsorption by BIBC ranged from 5.0 to 7.0. The maximum adsorption capacities of phosphorus (according to the Langmuir model) were 3.62, 4.06, and 4.32 mg g-1 at temperatures of 25, 35, and 45 °C, respectively. Electrostatic interaction, surface adsorption of phosphorus on BIBC, and ion exchange were the main mechanisms of phosphorus adsorption. According to XPS results, Fe2p was involved in the adsorption reaction. The adsorption of phosphorus by BIBC is considered to be mainly chemical adsorption. The BIBC was stable under a pH range from 4.0 to 10.0 and secondary pollution did not result.


2017 ◽  
Vol 55 (2) ◽  
pp. 285-293 ◽  
Author(s):  
N. Veronica ◽  
D. Subrahmanyam ◽  
T. Kiran ◽  
P. Yugandhar ◽  
V. P. Bhadana ◽  
...  

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