23
single location where loose straw is piled, e.g., it can be hauled, either by a twowheel tractor or a pick-up truck, to where the stationary baler is located.
Round balers need to stop intermittently whenever bales are being discharged
from the machines. Square balers, on the other hand, can be operated continuously
in the field. Square bales are easy to pile and require much less space for storage
than round bales. However, energy efficiency almost works out the same for both
balers because a round baler has fewer power requirements than a square baler,
which needs more power for compressing and baling. Round balers can also run
much faster than square balers.
2.5 High-Density Straw Compacting, Briquetting,
and Pelletizing
2.5.1 Compacting
Transporting bales after collection from the field has become feasible and costs less
than transporting loose straw. However, for high-end markets, such as industrial
cattle farms, large amounts of rice straw (e.g., more than 20,000 t for a cattle farm
in Vietnam) must be transported long distances (sometimes more than 500 km) and
stored for from 3 to 6 months. Round bales should be compacted into larger and
higher-density square bales to reduce transportation and storage costs.
Compacting the bales utilizes technologies that apply high pressure, such as
screw or piston presses. A few compacting machines that use the piston press are
found in Asia. Two common variations are the vertical and horizontal compacting
systems.
Rice Straw Collection in Thailand, China, and India
In Thailand, government prohibition of rice straw burning in fields has
prompted farmers and the private sector to collect straw left in the field and
sell it for alternative uses such as mulching and animal feedstock. The use of
square balers to optimize the collection of the straw for biomass power generation has also become popular in Thailand. The cost of collection with
square balers varies from US$ 18–20 t
−1
for both of small sand large square
bales in Thailand (Delivand et al. 2011).
In China, the need for systems to collect, process, and transport rice straw
encouraged the introduction of many types of balers. Small, round steel-roll
balers are popular in the countryside, given their simple structure and low
power requirements of about 13–20 kW (Wang et al. 2011).
In India, around 120,000 t of rice straw are collected annually to add 12
megawatts of electricity to the local power grid. The huge demand for rice
straw requires larger balers, such as the widely used commercial CLAAS
Markant 55 (Hegazy and Sandro 2016).
2 Mechanized Collection and Densification of Rice Straw
single location where loose straw is piled, e.g., it can be hauled, either by a twowheel tractor or a pick-up truck, to where the stationary baler is located.
Round balers need to stop intermittently whenever bales are being discharged
from the machines. Square balers, on the other hand, can be operated continuously
in the field. Square bales are easy to pile and require much less space for storage
than round bales. However, energy efficiency almost works out the same for both
balers because a round baler has fewer power requirements than a square baler,
which needs more power for compressing and baling. Round balers can also run
much faster than square balers.
2.5 High-Density Straw Compacting, Briquetting,
and Pelletizing
2.5.1 Compacting
Transporting bales after collection from the field has become feasible and costs less
than transporting loose straw. However, for high-end markets, such as industrial
cattle farms, large amounts of rice straw (e.g., more than 20,000 t for a cattle farm
in Vietnam) must be transported long distances (sometimes more than 500 km) and
stored for from 3 to 6 months. Round bales should be compacted into larger and
higher-density square bales to reduce transportation and storage costs.
Compacting the bales utilizes technologies that apply high pressure, such as
screw or piston presses. A few compacting machines that use the piston press are
found in Asia. Two common variations are the vertical and horizontal compacting
systems.
Rice Straw Collection in Thailand, China, and India
In Thailand, government prohibition of rice straw burning in fields has
prompted farmers and the private sector to collect straw left in the field and
sell it for alternative uses such as mulching and animal feedstock. The use of
square balers to optimize the collection of the straw for biomass power generation has also become popular in Thailand. The cost of collection with
square balers varies from US$ 18–20 t
−1
for both of small sand large square
bales in Thailand (Delivand et al. 2011).
In China, the need for systems to collect, process, and transport rice straw
encouraged the introduction of many types of balers. Small, round steel-roll
balers are popular in the countryside, given their simple structure and low
power requirements of about 13–20 kW (Wang et al. 2011).
In India, around 120,000 t of rice straw are collected annually to add 12
megawatts of electricity to the local power grid. The huge demand for rice
straw requires larger balers, such as the widely used commercial CLAAS
Markant 55 (Hegazy and Sandro 2016).
2 Mechanized Collection and Densification of Rice Straw