2.2 Preparation of Briquettes
The peanut shells briquettes were formulated in two
different processing. The first was produced from
charcoal that was carbonized at 250 0C for 2.5 hours,
called PSCB, and the second was fabricated
thoroughly for briquette productions PSPB. These
samples were respectively milled and filtered with a
particle size of around 100 mesh. The starch was
dissolved by the concentration of 24.6 wt% and
mixed with briquette samples in the ratio of 1:7.
Briquette samples mixture loaded into a cylindrical
mould (size 3/4 inch length 5 cm compression 276.8
Pa) to construct the briquettes at room temperature. A
simple apparatus was manually used to compress the
briquettes for 2 hours. The densified briquette was
pushed out and dried to obtain the briquettes (Moki,
et al., 2018) then characterized.
2.3 Determination of Physico-chemical
Characteristics
The samples that have been dried are then
characterized. The Physico-chemical parameters of
the briquette samples were volatile matter, caloric
value, ash content, moisture content, and fixed
Carbon. The calorific value was calculated using a
bomb calorimeter (AC-500) at the Laboratory of
Energy and Mineral Resource (ESDM), South
Sulawesi Province. The volatile matter (VM) and ash
contents (AC) were calculated using one gram of
briquette sample in a crucible and heated at the
furnace. The VM and AC were burned at a
temperature of 900°C for 7 minutes and 850°C for 2
hours. Similarly, the moisture content (MC) was
conducted at temperature 105°C in oven drying until
the sample's mass was constant. The weight change
determine the volatile matter (%VM), ash content
(%AC), and moisture content (%MC) using Equation
1 [(Moki, et al., 2018), (Nazari, et al., 2019)]:
%VM,%AC,and %MC=(W_i-W_f)/W_i ×100 %
(1)
where Wi is the initial weight, and Wf is the final
weight of the sample after processing the briquette
treatments. Furthermore, the percentage fixed Carbon
(%FC) was analyzed by the substitution of the value
of %VM, %AC, and %MC to Equation 2 [(Moki, et
al., 2018), (Nazari, et al., 2019)]:
%FC=100 %-(%VM+%AC+%MC) (2)
3 RESULTS AND DISCUSSIONS
The conversion of peanut or groundnut shells into the
briquette as fuel was successfully done, as reported in
many previous works [(Oni K, et al., 2020), (Wibowo
& Lestari, 2020), (Oyelaran, et al., 2015)] with
carbonization processing or directly into a pellet
form. The carbonization process of briquette is the
way to formulate the briquette from the charcoal by
thermal treatment. It was called in some definitions,
such as pyrolysis, torrefaction, and hydrothermal
carbonization, depending on the thermal
transformation of biomass (Krylova & Zaichenko,
2018). Meanwhile, the others have been processed by
compacting the groundnut shell biomass briquettes
with waste paper (Oyelaran, et al., 2015). This
process was proposed to define the improvement of
handling properties and volumetric with uniform
shape and sizes at a low cost (Oyelaran, et al., 2015).
However, considering the advantages and
disadvantages of these two different processes is an
important option to select and suitable for users.
Figure 1 shows the different processes of peanut shell
briquette production.
Figure 1: The Process of Production Briquette Samples
As shown in Figure 1, the briquette of peanut
shells formulated without carbonization is a
yellowish colour and has been called the Peanut
Shells Pellet Briquette (PSPB). Others with
carbonization processes have been famously named
Peanut Shells Charcoal Briquette (PSCB) is blackish.
According to the previous report, changing the colour
caused the heating process to obtain the charcoal of
peanut shells (Wibowo & Lestari, 2020), which
mainly contained solid Carbon (Krylova &
Zaichenko, 2018). The visual investigation by
touching the briquettes showed that both were
smooth; the PSPB has produced an odour and no
black mark in hand than the PSCB.
Furthermore, the comparison of the Physico-
chemical parameters has shown in Table 1. The
parameters are caloric value, moisture content, ash