COMPOSTING

Composting

controlled

decomposition of organic matter by

micro-organisms, mainly bacteria and

fungi, into a humus-like product.

SOIL ENRICHMENT
WASTE REDUCTION
COST SAVING
ENVIRONMENTAL PROTECTION

ENVIRONMENTAL IMPACT OF COMPOSTING

Particle Size
Moisture Content
C:N Ratio
Oxygen
pH

FACTORS AFFECTING

COMPOST PROCESS

PARTICLE SIZE

Smaller particles produce more homogeneous mixture and faster

decomposition

Moisture Content

Supply water to maintain microbial growth

C:N Ratio

Carbon provides energy for metabolism and synthesis of new cells

Nitrogen is used for cell growth and function

Oxygen

essential for metabolism and respiration of aerobic microorganism

used for oxidizing organic component of waste

pH

affects microbial activity and ammonia emission

54°C – 60°C

TEMP RANGE

25:1 – 30:1

C:N RATIO

> 5%

Aeration, percent oxygen

50% – 60%

Moisture content RANGE

5mm – 50mm

Particle size RANGE

30% – 36%

Porosity RANGE

5.5 – 8.0

pH RANGE

Windrow composting

Aerated static pile

In-vessel system

TYPES OF

COMPOSTING

WINDROW COMPOSTING

production of

compost by piling in long rows.

1 m – 2 m high and 2 m – 5 m

It should be _____ wide

at the base.

4 MONTHS

Typical composting time is around ____ FOR WINDROW.

AERATED STATIC PILE

The compost are aerated by a system of

perforated pipes placed in the layers of

compost pile.

2.4 m – 4.5 m

The compost mixture height generally ranges

from ____ and the width should be

twice the depth.

4 WEEKS

Typical composting time is around ___ FOR AERATED

IN-VESSEL COMPOSTING SYSTEM

Organic material is enclosed on a

structure of container to control

temperature, moisture, and airflow

over specific detention time.

7-30 days

Composting time in this type is

around ___ depending on the

type of materials. (IN-VESSEL)