| |
Limed Biosolids |
Digested Biosolids |
Dried Biosolids |
| End product Acceptability |
• Highly acceptable
• Soil like composition
• 50-55% Solids
• Easily spread by
farmyard spreader
• Contains valuable
nutrients and lime |
• Still identifiable with origin
• Sticky-difficult to spread
• Stockpiles re-wet
and smelly |
• Dusty Risk of fire |
| Capital Costs |
• Low
• Easy to install
• Available as mobile unit
|
• Very high |
• Very high |
| Running Costs |
• Medium
• Important to choose
correct lime system |
• Low-medium |
• High (drying water) |
| Ease of Operation |
• Simple
• Easy to verify
• Pasteurisation by
Temp./Time/pH
• Easy to recycle |
• Difficult
• Sensitive Microbes
• Impossible to recycle
• In U.S, retrofitting lime
as a backdrop |
• Difficult
• Large investment in
equipment
• Problematic |
| Ease of Quality Control |
• Simple
• Temp./30 mins.; Easy to
measure and record |
• Difficult
• Measuring Temp. over
long period
from 2-12 days |
• Simple
• Easy to record |