66
3 Bio-augmented Composting of Organic Wastes in Villages and Towns
moderate moisture content for the compost pile is in the range of 55–65%. In practical application, the simple method to make judgment is to tightly hold the materials
in hands to find water between fingers while water does not drop.
3.1.2.4 Particle Size
The oxygen for fermentation is supplied through pores in particles of fermenting
materials. The porosity and pore size depend on the particle size and structural
strength. Paper, animals, plants, fabrics, etc. can increase their densities when they
are in water under compression and pores between their particles greatly decline,
which is unfavorable for ventilation and oxygen supply. The suitable size of particles
is generally in the range of 12–60 mm.
3.1.2.5 Turning
Turning for oxygen supply is one of fundamental conditions of production of aerobic
composting. The purpose of turning is to provide oxygen in order to further accelerate
the fermentation process of microorganisms, adjust the temperature of the pile and
dry the windrows. If the times of turning are low, the ventilation rate is low so
that there is no sufficient oxygen for microorganisms, restricting the increase of
fermentation temperature. However, excessive turning times can cause the heat loss of
the windrows, which influences the non-hazardous degree of fermentation. Generally,
it is necessary to turn the compost piles for 2–3 times during the fermentation based
on actual condition.
3.2 Development of Complex Microbial Inoculants
3.2.1 Complex Microbial Inoculants for Degrading
Lignocelluloses
The microbial community in mature compost was taken as materials and the bran
rich in cellulose was used as carbon source to thus promote the proliferation of
cellulose-decomposing bacteria and induce microorganisms to generate ligninase.
In this way, efficient complex microbial inoculants for degrading lignocelluloses can
be prepared.
Culture of the complex microbial inoculants: Ten grams of mature compost was
added into 1000 mL of peptone cellulose solution (PCS) medium to statically culture
the complex microbial inoculants at 50 °C for 7 days. The PCS medium was prepared
with 5 g of peptone, 5 g of NaCl, 2 g of CaCO 3 , 1 g of yeast powder, 5 g of bran and
1000 mL of deionized water and sterilized for 20 min at 121 °C. Moreover, 10 mL of
3 Bio-augmented Composting of Organic Wastes in Villages and Towns
moderate moisture content for the compost pile is in the range of 55–65%. In practical application, the simple method to make judgment is to tightly hold the materials
in hands to find water between fingers while water does not drop.
3.1.2.4 Particle Size
The oxygen for fermentation is supplied through pores in particles of fermenting
materials. The porosity and pore size depend on the particle size and structural
strength. Paper, animals, plants, fabrics, etc. can increase their densities when they
are in water under compression and pores between their particles greatly decline,
which is unfavorable for ventilation and oxygen supply. The suitable size of particles
is generally in the range of 12–60 mm.
3.1.2.5 Turning
Turning for oxygen supply is one of fundamental conditions of production of aerobic
composting. The purpose of turning is to provide oxygen in order to further accelerate
the fermentation process of microorganisms, adjust the temperature of the pile and
dry the windrows. If the times of turning are low, the ventilation rate is low so
that there is no sufficient oxygen for microorganisms, restricting the increase of
fermentation temperature. However, excessive turning times can cause the heat loss of
the windrows, which influences the non-hazardous degree of fermentation. Generally,
it is necessary to turn the compost piles for 2–3 times during the fermentation based
on actual condition.
3.2 Development of Complex Microbial Inoculants
3.2.1 Complex Microbial Inoculants for Degrading
Lignocelluloses
The microbial community in mature compost was taken as materials and the bran
rich in cellulose was used as carbon source to thus promote the proliferation of
cellulose-decomposing bacteria and induce microorganisms to generate ligninase.
In this way, efficient complex microbial inoculants for degrading lignocelluloses can
be prepared.
Culture of the complex microbial inoculants: Ten grams of mature compost was
added into 1000 mL of peptone cellulose solution (PCS) medium to statically culture
the complex microbial inoculants at 50 °C for 7 days. The PCS medium was prepared
with 5 g of peptone, 5 g of NaCl, 2 g of CaCO 3 , 1 g of yeast powder, 5 g of bran and
1000 mL of deionized water and sterilized for 20 min at 121 °C. Moreover, 10 mL of