Organic Waste Recycling

Characteristics of organic wastes 79

2.6.3 Feasibility analysis

The feasibility analysis has to prove whether each or a combination of the above
options are technically and economically feasible and whether they contribute to
the environmental improvement. The technically non-feasible options and the
options without significant environmental benefits can be eliminated. All
remaining options can, in principle, be implemented. Example 2.2 compares
financial feasibility of two CP options

Example 2.2

The sausage industry from Example 2.1 needs to reduce the quantity of waste
generated by considering two alternatives. For the first alternative, a recovering
machine will be set up to recover the small pieces of meat contained in the
wastewater back to the grinding process. The density of the wastewater will then
be reduced to 1,050 kg/m^3. For the second alternative, the old grinding machine
will be replaced by a new one, so the wastewater generated will be reduced to
4m^3 /hr (density is 1200 m^3 /kg) and ground meat output will be 9,250 kg/hr. The
investment costs of the recovering machine and the new grinding machine are
$100 and $150, respectively. The two machines are assumed to have the same
lifetime and the wastewater treatment costs are the same.

Solution

A. For the first alternative which employs a recovering machine

Wastewater generated 5 × 1,050 = 5,250 kg/hr

Small pieces of meat recovered 6,000- 5,250 = 750 kg/hr

Total ground meat 8,500 + 750 = 9,250 kg/hr

Production quanity per investment cost 9,250/100 = 92.5 kg/hr/$

B. For the second alternative which employs a new grinding machine

Wastewater generated 4 × 1,200 = 4,800 kg/hr

Ground meat 9,250 kg/hr

Production quanity per investment cost 9,250/150 = 61.67 kg/hr/$