CO-COMBUSTION MODELLING OF RICE HUSK AND PLASTIC BAGS AS ENERGY SOURCE IN INDONESIA

Muhammad Anshar, Farid Nasir Ani, Ab Saman Kader

The International Conference on Computational Fluid Dynamics in Research and Industry

2015 (CFDRI 2015)

KUALA LUMPUR, 18-19 AGUSTUS 2015

INTRODUCTION

The inventory EE in Indonesia is still very limited. The power needs of society and industry is increasing every year. Fossil energy sources are a major source of power generation tend to decrease dramatically and environmental impacts. The potential of RH and the PB in Indonesia is quite large which is produced every year. Based on previous studies, Indonesia has the potential of RH around 13.81×106 tons. The potential of PSW an average of about 252,945 tons/year generated from the year 2008-2010, This potential can be exploited as a source of EE as well as the results of previous studies, in Thailand and in India.

The mass composition between 90% of RH and 10% of PB (RH90+PB10).

Calorific value (CV) of RH is obtained based on the standard procedure of ASTM D.5865 using Bomb Calorimeter.

Proximate analysis was carried out under the standard procedure ASTM D 3172 - 3175 and ISO 565,

Ultimate analysis was performed under the standard procedure ASTM D 3176, ASTM D 4239, and ASTM D 5373.

Geometry of the furnace is obtained by Autodesk Mechanical Desktop software, Meshing done with Gambit software

Co-combustion modeling of RH90+PB10 performed using FLIC and Ansys - Fluent software.

MATERIALS AND METHODS

MATERIALS AND METHODS

Fig-1. Geometry models of furnaces are used for small power plants i.e. 7.5×5.7×12 m.

MATERIALS AND METHODS

BOUNDARY CONDITION

This modeling using the boundary condition: Fuel feed rate of about 6,575 kg/h at 298 K, The AFR stoichiometric of about 1.2, The primary air about 6 kg/s at 453 K, The secondary air 1 and 2 of about 3.2 kg/s at around 453 K, The capacity of 10 MW.

.

RESULTS AND DISCUSSION

Table 1. Calorific value, proximate and ultimate analysis of RH and RH90+PB10

.Fuel

materials

CV(kJ/kg)

FC (%)

VM(%)

MC (%)

C (%)

H (%)

O(%)

N (%)

S(%)

Ash (%)

RH 13442 14.81 55.62 10.46 39.28 5.08 35.81 0.64 0.08 19.11

RH90+PB10 18847 13.62 58.65 9.68 42.21 5.82 33.45 0.64 0.08 19.11

Table 2. Modeling results of RH90+PB10 and RH on grate bed furnace.

Fuel materials

Combustion characteristic in grate bed furnace Tg

max. (K)

Tg average (K)

Tg exit (K)

Vg

(m/s) ηsg (%)

Overall AFR Stoich.

Total fuel input (kg/h)

Total energy in fuel input (MWt)

RH 1680 1138 950 8.51 100 0.837 6575.35 24.55 RH90+PB10 1710 1186 1100 9 100 0.726 6575.35 34.42

Table 2, show the addition of about10% PB to the RH (co-combustion of RH90+PB10) provide significant effect on several variables combustion.

Input data used for modeling the data that was the result of experiments, as presented in Table 1

Figure-2. Gas temperature characteristic of RH90+PB10 in grate bed

RESULTS AND DISCUSSION

Figure-3. Profile of CO, CO2, O2, and H2O of RH90+PB10 at the top bed.

RESULTS AND DISCUSSION

Figure-4. Profile of combustion gas of RH90+PB10 at the top bed.

RESULTS AND DISCUSSION

Figure-5. Contours of of RH90+PB10: a) Static temperature (K); b) CO (%)

RESULTS AND DISCUSSION

Figure-5. Contours of of RH90+PB10: c) CO2 (%); d) H2O (%).

RESULTS AND DISCUSSION

CONCLUSION

The results of the co-combustion modeling of RH90+PB10 showed the ability and feasibility as an alternative source of electrical energy in Indonesia. The application of the co-combustion of RH90+PB10 as a source of energy could be one solution to meet the electrical energy needs and overcome the plastic bag waste pollution in Indonesia.