Municipal wastewater phosphorus removal by coagulation
Kai Yang1, Zhenhua Li, Huaiyu Zhang
1School of Civil Engineering, Wuhan University, Wuhan, 430072 China.
Environmental Technology
|June 15, 2010
Summary
This study shows that phosphorus adsorption using goethite-coated silica sand is more effective than chemical precipitation for wastewater treatment. This method can remove approximately 65% of phosphorus from secondary effluent.
Area of Science:
- Environmental Science
- Water Treatment Technologies
- Chemical Engineering
Background:
- Phosphorus is a key pollutant in wastewater, contributing to eutrophication.
- Effective phosphorus removal is crucial for protecting aquatic ecosystems.
- Current wastewater treatment methods require optimization for enhanced phosphorus removal.
Purpose of the Study:
- To compare the efficacy of adsorption and chemical precipitation for phosphorus removal from wastewater.
- To evaluate the performance of goethite-coated silica sand in adsorptive phosphorus removal.
- To determine the optimal method for phosphorus management in municipal wastewater.
Main Methods:
- Wastewater phosphorus removal was investigated using adsorption and precipitation techniques.
- Precipitation tests utilized four common metal salt coagulants with secondary effluent.
- Adsorption experiments were conducted using column studies with goethite-coated silica sand.
Main Results:
- Adsorption demonstrated a more significant role in phosphorus removal compared to precipitation.
- Column experiments indicated that goethite-coated silica sand retained approximately 65% of phosphorus.
- The breakthrough curve analysis confirmed the efficiency of the adsorption process.
Conclusions:
- Adsorption using goethite-coated silica sand is a highly effective method for wastewater phosphorus removal.
- This adsorption process is superior to chemical precipitation with common metal salts.
- The findings support the implementation of advanced adsorption techniques for sustainable water management.
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