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 485

Fig. 5 Melted plastic agglomeration in the low temperature zone of gasifier

gasi er. This led to the plastic melting and a large amount of melted plastic

solidi er, as

shown in Fig. 5 . Therefore, the amount of charcoal was increased to 70 kg for test
no. 3 to 17 and 100 kg for test no. 18 as the increasing amount of dense-RDF to
284.5 kg.
By increasing the amount of charcoal supplied in the gasi

ed and agglomerated at the low temperature zone at the bottom of gasi

er, the high tem-
perature can be promoted and the temperature in the combustion zone was suffi- -

ciently high in order to provide the heat transfer throughout the gasi er for the

continuous gasi cation process in the test no. 3 to 17. However, the problem of

melted plastic agglomeration occurred again in test no. 18 which used 100 % dense-
RDF as feedstock, as a result, the gasi cation process was interrupted. It can be

concluded that 100 % dense-RDF cannot be used as single fuel in the gasi cation

process. This can be explained by the high amount of volatile matter in fuel. It has
to be mixed with wood chip or fuel with high amount of

xed carbon.
Considering the producer gas composition, CO and H 2 was the dominant
composition in producer gas with the value ranging from 13.40 to 20.59 vol% and
7.81 to 14.49 vol%, respectively. The lower heating value of 3.12

3.99 MJ/Nm 3
was obtained. Table 8 shows the performance of gasification process for accumu-
lated 200 h test run in terms of producer gas composition, producer gas lower
heating value, and cold gas ef

-

ciency.
With regard to the performance of engine-generator for power production, the
producer gas can replace 64

80 % of diesel and the overall ef ciency for power

-

production via dense-RDF gasi cation process varied from 9.74 to 18.55 % at the

constant power production 24 kW. The rate of solid fuel consumption per a unit of
power generation ranged between 0.80 and 1.50 kg/kWh. The performance of
engine-generator for power production is listed in Table 9 .
Although there was gas-cleaning process, the paper

filter was placed to trap the
particulates in the producer gas before the producer gas entering the engine. The
amount of particulate in the clean producer gas ranged from 14 to 56 mg/Nm 3 ,
which is lower than the engine requirement (less than 50 mg/Nm 3 ; Bandi 2003 ).
Even some soot and particulates were removed from producer gas, during the