Disposing Carcass and by-products

1. Disposing Carcass and By-Products
Mohammad Hafizur Rahman

2. Burial
Fig: Trench Burial

3. Burning

4. Incineration
Incineration is the process where animal carcasses or by-products are
burnt at high temperatures (P-850 ºC) to produce an inorganic ash.
The process is expected to destroy all infective agents.
Ash typically represents 1–5% of
initial carcass volume. The
principal concern with incineration
of carcasses relates to gaseous
emissions; however, small-capacity
incinerators are responsible for air
pollution.
Fig: Incinerator managing poultry carcass
Propane, diesel or natural gas are
used as auxiliary fuel in
Incineration process.

5. Rendering
Rendering entails crushing carcasses and animal by-products into
particles of a uniform size, heating the particles and then separating
out the fat, proteinaceous material and water into, where possible,
useful products including meat and bone meal and tallow. Ordinarily,
rendering is a safe, rapid, and economical method of disposal of
carcasses and by-products.
Rendering has a high energy
demand but if tallow is
recovered for subsequent energy
production then the net GHG
emissions are likely to be low.

6. Alkaline Hydrolysis
What remains are the mineral constituents of the bones and teeth. This
process requires specialized equipment and operates at 150o C for 3-6
hours. It completely inactivates pathogens with the exception of prions
where infectivity is reduced, and is environmentally responsible.
Alkaline hydrolysis consists of treating
carcasses or tissue in an aqueous alkaline
solution at elevated temperatures under
pressure. It converts proteins, nucleic
acids, and lipids of all cells and tissues
into a sterile aqueous solution of small
peptides, amino acids, sugars, and soap.

7. Composting
Fig: Bin Composting Fig: Windrow Composting Fig: Vessel Composting
Aerobic composting is widely used to dispose of livestock mortalities.
Composting is a simple technique that can be undertaken on-farm
using windrow and bin composting or in-vessel techniques.
Composting process involves the layering of carcasses between strata
of carbon-rich substrate such as straw, sawdust or rice hulks with a
final covering of carbon-rich substrate over the entire pile. Depending
on carcass weights, the waste material may decompose at rates as high
as 1-2 kg per day.
The process essentially occurs in two phases – a primary, thermophilic
phase (temperatures up to 70 ºC generated for a number of weeks) and a
secondary, mesophilic phase (typically 30-40 ºC) for a number of
months.

8. Technology Comparisons
(Brglez, 2003; Point scale 1=Good, 2=Average, and 3=Poor)

9. Thank you for your attention.
Biogas production technique