Calculation Method for Fly Ash Generation from Municipal Solid Waste (MSW) Incineration
1. Basic Calculation of Fly Ash Generation Rate
Typical Yield Range
Fly ash accounts for 3%~5% of the total waste incinerated (can drop to 2%~3% in cities with well-sorted waste).
Example: For a 300-ton/day incineration facility, fly ash production is 9~15 tons/day.
Fluidized bed incineration can produce >10% fly ash, significantly higher than grate furnaces.
Fly Ash Quantity=Waste Processing Volume×Fly Ash Yield Rate×(1−Residue Moisture Content)
(Moisture content in residue should be adjusted based on actual test data.)
2. Key Influencing Factors
Waste Composition:
High chlorine content (e.g., food waste) significantly increases fly ash generation.
Incineration Technology:
Grate furnaces produce fly ash dominated by chlorides.
Fluidized bed incineration generates more inorganic components like SiO₂.
Flue Gas Treatment Systems:
Activated carbon injection and wet acid scrubbing can increase fly ash yield.
3. Practical Case Studies
Zhengzhou, China:
Five incineration plants process 10,250 tons/day, producing ~410 tons/day of fly ash (yield rate: 4%).
Shanghai, China:
16 incineration plants handle 28,895 tons/day, generating ~900 tons/day of fly ash (yield rate: 3.1%).
4. Professional Recommendations
Laboratory Analysis:
Conduct proximate analysis (volatiles, fixed carbon, etc.) to refine yield estimates.
Dynamic Adjustment:
Monitor flue gas composition in real time and optimize air supply, temperature, and other parameters to minimize fly ash production.
For more precise calculations, recommend modeling based on specific incinerator parameters and waste sampling data.