compost and Landfills are most important for balance soil. it helps in maintain the soil to has enough nutrients to grow health plants without destroying natural environment and living things in surroundings. you will find sufficient material about composts and landfills in this presentation.

2. Biotechnology
Presented by: Aneela Rafiq

3. Compost and landfills

4. Composts
• Natural Fertilisers
• Food for plants
• Plants needs micro and macro-nutrients
• Nitrogen (N), phosphorus (P) and potassium (K), often
written as NPK and in small quantities, e.g. copper
(Cu), manganese (Mn), magnesium (Mg), iron (Fe),
sulphur (S) and others
• Compost feeds the soil with humus and plant
nutrients.
• Natural fertilizer comes from animal wastes
and plants.

5. Characteristic of composts
• Improves the organic matter in the soil by
providing humus;
• Helps the soil hold both water and air for
plants and
• Makes trace elements or micronutrients
available to plants

6. Components of compost
1. Plant materials, both dry and green
• Weeds, grasses
• Crop residues: stems, leaves, straw and chaff1 of all field crops –
both big and small – cereals, pulses, oil crops, horticultural crops
and spices
• Garden wastes – old leaves, dead flowers, hedge trimmings,
grass cuttings
• Dropped leaves and stems from almost any tree and bush except
plants which have tough leaves, or leaves and stems with a
strong smell or liquid when crushed, like Eucalyptus, Australian
Acacia, Euphorbia.

7. Cont…
The contributions of dry and green plant materials
• Dry materials give structure to the compost making
process; they provide space for air to circulate so
that the micro-organisms can be active and make
heat.

8. Cont…
2. Water
• Enough water is needed to wet all the
materials and keep them moist
• Water does NOT need to be clean like
drinking water. It can come from:
• Collected rainwater;
• Collected wastewater, e.g. from washing
pots and pans, clothes, floors, etc.;
• Animal urine; or Human urine.

9. Cont…
3. Animal materials
• Dung and droppings from all types of domestic
animals, including from horses, mules, donkeys
and chicken, from night pens and shelters, or
collected from fields.
• Chicken droppings are important to include
because they are rich in nitrogen.
• Urine from cattle and people

10. Cont…
4. Compost making aids – “farmers’ friends”
• Micro-organisms (fungi and bacteria) and
smaller animals (many types of worms,
including earthworms, nematodes, beetles
and other insects) turn waste materials into
mature compost.
• These are found naturally in good fertile
soils like those from forests, old animal
dung and old compost.

11. Cont…
5. Air
• Including dry materials in the compost, e.g. old
leaves and stalks, provides space for air to circulate
inside the compost.

12. Cont…
6. Heat
• Decomposition of organic wastes produces
heat.
• Compost needs to be kept hot and moist so
the plant and animal materials can be broken
down quickly and thoroughly.
• Heat destroys most of the weed seeds, fungal
diseases, pests and parasites

13. Components of compost

14. Landfill cell Design

15. Landfill
• Landfill is often regarded as the last resort waste
management option.
• landfilling is an active treatment process.
• An engineered landfill is designed to contain waste
and its decomposition products until they present no
significant risks to health or the environment.

16. Cont…
• A common landfill classification system reflects the
type of waste each receives. There are landfills for:
• Hazardous wastes,
• Municipal wastes and
• Inert wastes (inert wastes imposes a long-term
responsibility for monitoring and supervision.)

17. Controlled contaminant release
• leachate levels are permitted to rise within the
waste, permitting gradual migration into the
ground.
• Naturally, this approach is not suited to every
location and geological setting, and full risk and
environmental impact assessment approaches
should be carried out before development is
approved

18. Biological processes
• Generally, more than half of household waste is
organic.
• Aerobic hydrolysis
• microorganisms convert some carbohydrates to
simple sugars, CO 2 and water
• when carbohydrates, lipids and proteins are
broken down into volatile acids, acetate, CO 2 ,
H 2 and acetogenesis
• Carbohydrates are also transformed into acetic
acid; methanogenesis (in which bacteria convert
acetic acid to methane and CO 2)
• Finally, conditions may become aerobic again as
the waste stabilizes

19. Chemical processes
• Two general types of chemical reactions
take place within landfilled waste
• Firstly, oxidation , using trapped oxygen,
which soon becomes depleted.
• Secondly, acid-metal reactions , due to the
presence of organic acids and CO 2 .
• These processes mobilise metallic ions and
salts which are potential pollutants.
• However, once methane generation is
established the landfill becomes less acidic
and metals are generally retained within
the waste mass

20. Physical processes
• Compaction of waste has a strong bearing on its
behavior.
• This process begins at the collection stage and
continues within the landfill.
• High densities reduce future settlement and limit
potential moisture up-take.

21. Pollution from landfills
• A waste disposal facility must guarantee
adequate control over the two main types of
pollution –
• Leachate
• Leachate is generated as a result of moisture
entry into a landfill, either as rain, snow
melt, run-on or as moisture in the waste
itself.
• landfill gas
• Landfill gas has a distinctive and unpleasant
odour, due to the presence of mercaptans
and thiols

22. Thank
you