In-Depth Performance Evaluation of RDF from Landfill Reclamation for Green Electricity Generation in a Downdraft Gasifier - Novel Combustion Concepts for Sustainable Energy Development - page 481

For the up-scaling test, 30 kg of charcoal was fed into the bottom of gasi er and

ignited in order to preheat the gasi er, and 300 kg of dense-RDF was introduced

into the downdraft gasi er per batch. To start the gasi cation process, the air fl ow

rate of 75 Nm 3 /h was supplied into the gasi

cation process, the
samples of producer gas were taken for analysis. To optimize the operating con-
dition, the experiment was repeated with the air

er. During the gasi

flow rate of 85 and 101 Nm 3 /h.
To study the feasibility of long-term test run for 200 accumulated operating
hour, 60

fl

100 kg of charcoal was fed into the bottom of gasi er and ignited in order

-

to preheat the gasi er; whereas wood chip was also supplied together with dense-

RDF at the different weight ratio of dense-RDF to wood chip of 50:50, 75:25, and
100:0. After all feedstock were put into the gasi er, the ignition process was

conducted and then air was supplied into the gasi er at the optimum condition to

promote the gasi cation process. During the steady state experiment, the producer

gas was taken at the exit of gasi er for the investigation of producer gas compo-

sition and heating value. The system performance for power production was also
evaluated at the same time. The gasi cation process was terminated when it was

observed that no producer gas generated. The whole experiment was repeated again
until the operation test run reached 200 h. In the accumulated 200 h test run, the
dual fuel engine-generator test using diesel and producer gas was performed.

2.2.4 Analysis

The composition of producer gas in terms of CO, H 2 ,CO 2 ,CH 4 , and N 2 was
analyzed by gas chromatography (GC) according to the ASTM standard. The
producer gas velocity is measured by the gas

flow meter, and the producer gas yield
at standard condition can be calculated by Eq. 1 , while the heating value of pro-
ducer gas was calculated by Eq. 2 .

fl

Q Producer gas ¼ Q 1 T 2
T 1

ð 1 Þ

;

flow rate of producer gas at the exit condition (m 3 /h), T 1 is
the temperature of producer gas at the gasi

where Q 1 is the volume fl

er exit ( ° C), and T 2 is the temperature at

standard condition (25 ° C).

LHV Producer gas ¼ R ð X i LHV i Þ ð 2 Þ

where LHV producer gas is the producer gas lower heating value (MJ/Nm 3 ), X i

rep-

resents each composition of producer gas yield (Nm 3 /h), and LHV i

is the lower

heating value of each producer gas composition (MJ/Nm 3 ).
The ef

ciency of the gasi cation process was expressed in term of cold gas

ef ciency de ned as the ratio of energy input into the gasi er to the energy output

from the gasi er, as given in Eq. 3 .