Treatment of phosphorus waste water using crystallization method
Dejun Bian1, Shengshu Ai1, Jing Liu2
1School of Water Conservancy and Environment, Changchun Institute of Technology, Changchun 130012, China.
Journal of Environmental Sciences (China)
|August 2, 2014
Summary
This study demonstrates an efficient phosphorus removal method from wastewater using crystallization with ethanol. The process achieved over 85% phosphorus removal, recovering valuable resources.
Area of Science:
- Environmental Science
- Chemical Engineering
- Water Treatment
Background:
- Phosphorus is a key limiting nutrient in aquatic ecosystems, and its excess leads to eutrophication.
- Effective phosphorus removal from wastewater is crucial for environmental protection.
- Resource recovery of phosphorus from wastewater is an important economic and environmental consideration.
Purpose of the Study:
- To investigate the crystallization method for treating high concentration phosphorus wastewater.
- To optimize parameters for efficient phosphorus removal and resource recovery.
- To analyze the impact of organic solvent selection and process conditions on crystal properties.
Main Methods:
- Crystallization technique was employed for phosphorus removal and recovery.
- Ethanol was used as the organic solvent (extractant).
- Key parameters investigated included solvent-to-wastewater ratio, precipitation time, and stirring speed.
Main Results:
- Ethanol proved effective as an extractant for phosphorus crystallization.
- Optimal conditions: ethanol-to-wastewater volume ratio of 1.5:1 and stirring speed around 200 rpm.
- These conditions resulted in rapid precipitation of fine, high-purity crystals.
- Phosphorus removal efficiency exceeded 85%.
Conclusions:
- The crystallization method using ethanol is a viable technique for high-efficiency phosphorus removal from wastewater.
- Optimized conditions ensure rapid crystal formation with desirable purity.
- This method contributes to both environmental remediation and phosphorus resource recycling.
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