Municipal Household Waste Autoclave
As government landfill taxes rise, local authorities are looking for the most efficient way to maximise the recycled waste. The autoclave process, which utilises proven treatment technology, converts around 80% of municipal solid waste into useful recyclates e.g. metals, plastics and useful recyclable material. The process utilises steam at high pressure and temperature within a rotating stainless steel pressure vessel.
Finite Element Analysis has become an essential tool in the qualification of unique equipment and provides a robust approach to the assessment of the waste autoclave pressure vessel and access doors to PD5500 “Specifications for Unfired Fusion Welded Pressure Vessels”.
An FE model was created of the autoclave and it was assessed under two load combinations. First it was subjected to operating pressure and temperature for a thermo-mechanical analysis. Then it was subjected to impact loads to simulate an object falling on it. The stresses in the autoclave were analysed and any areas over the allowable design values were analysed in more detail in accordance with the criteria in PD5500 to ensure the stress intensities here, calculated using stress linearization techniques, were below the code allowable values.