Biochar produced from biosolids using a single-mode microwave: Characterisation and its potential for phosphorus...

Area of Science:

• Environmental Science
• Materials Science
• Soil Science

Background:

• Biosolids generation is increasing, posing environmental challenges due to contaminants.
• Biosolids contain nutrients and can be repurposed, offering sustainable waste management solutions.
• Microwave assisted pyrolysis (MWAP) is a technology for converting biosolids into valuable biochar.

Purpose of the Study:

• To investigate the effect of pyrolysis temperature on biochar properties derived from biosolids.
• To evaluate the phosphorus adsorption capacity of the produced biochar.
• To assess the potential of MWAP-derived biochar for agricultural applications.

Main Methods:

• Biosolids were pyrolyzed using MWAP at temperatures ranging from 300°C to 800°C.
• Characterization of biochar included analysis of specific surface area, ash content, volatile content, pH, chemical composition, and crystalline phases.
• Preliminary phosphorus adsorption tests were conducted on the biochar samples.

Main Results:

• Pyrolysis temperature significantly influenced biochar's specific surface area, ash, and volatile content.
• Increasing pyrolysis temperature led to a decrease in biochar yield.
• The phosphorus adsorption capacity of the biochar was found to be approximately 15 mg/g.

Conclusions:

• MWAP is an effective method for managing biosolids and producing biochar.
• Biochar properties, particularly surface area, are temperature-dependent, impacting its suitability for soil amendment.
• The resulting biochar shows potential for land application, enhancing water and nutrient retention in soils.