INTRODUCTIONAccording to current demographic statistics, the world's population as of June 2021 was 7.9 billion, with a predicted increase to 9 billion in 2037 and 10 billion in 2057 [1]. The rapid yearly

growth rates of the world's population have a detrimental effect on environmental and food security issues; uncontrolled human activities have resulted in disturbing levels of pollution, climate

change, global warming, waste disposal, and natural resource depletion i.e. fossil fuel depletion [2]. As a consequence, these global issues need a solution that involves the circular bio-

economy playing a key role in reducing future global warming to 1.5 °C, as stated in the Paris Agreement [3]. In the context of contemporary energy situations, biomass is a potential eco-

friendly abundant alternative source of renewable energy. Biomass is a carbon-neutral energy source since the CO2 produced during its usage is equivalent to the CO2 absorbed from the

atmosphere during photosynthesis. It also contains less Sulphur, nitrogen, and heavy metals than coal [4]. Lignocellulosic biomass waste such as sugarcane bagasse can be used to produce

pyrolysis oil, which can be further upgraded through catalytic hydrothermal reforming to produce clean green fuel. Additional compounds may be synthesized from pyrolysis oil.. The purpose of

this study was to investigate the combustion properties of bagasse and bagasse pellets from western Kenya, as well as the feasibility of the bagasse materials for production of pyrolysis oil, a

precursor raw material for the processing of clean transport fuel analogous to gasoline.

Sampling:- was done in accordance to international standard BS EN 14778:2011. bagasse &

bagasse pellets collected West Kenya Sugar Company & Powerspot Pellets.

Sample Preparation:- done in accordance with BS EN 14780:2011. Fresh bagasse samples were

dried under natural atmospheric conditions to a moisture content of ≤ 10%. Bagasse pellets were

not dried since processing of bagasse to pellets in the factory requires a drying pre-treatment to a

moisture content of ≤ 10%.

Characterization of Biomass/Feedstock Analysis:-

The samples were analyzed for Carbon (C), Hydrogen (H), Nitrogen (N), Sulphur (S), Oxygen (O)

with oxygen content determined by difference. The High Heating Value was determined directly

using an oxygen bomb calorimeter. Low Heating Value was calculated from the HHV and the

elemental composition of the samples. A proximate analysis was also undertaken in order to

determine the Moisture content, Ash content, Volatile Matter content and Fixed C content. All

analyses were conducted in line with the BS EN ISO procedures for solid biofuels.

Pyrolysis Experiment:- carried out to a maximum of 500 oC, heating rate of 50 oC min-1, particle

size of 0.5mm to 0.6mm, 1-10 s of hot vapour residence time.

METHODS DISCUSSION

CONCLUSIONS

Acknowledgement

World Bank, Kenya Climate Smart Agriculture Project, Ministry of Agriculture Livestock Fisheries and Cooperatives, Agriculture and Food Authority, University of Nairobi, Celignis Analytical, Dr Beth Ndunda, Dr

Fredrick Mwazighe, Dr Richard Kimilu, Mr Jackstone Anyona and Mr Job Bosire.

References

United Nations, “World Population Clock: 7.9 Billion People (2021) - Worldometer,” 2021. https://www.worldometers.info/world-population/ (accessed Jun. 21, 2021). D. Hoornweg, P. Bhada-Tata, and C.

Kennedy, “Waste production must peak this century,” Nature, vol. 502, no. 7473, pp. 615–617, 2013, doi: 10.1038/502615a. M. Carus and L. Dammer, “The Circular Bioeconomy - Concepts, Opportunities, and

Limitations,” Ind. Biotechnol., vol. 14, no. 2, pp. 83–91, 2018, doi: 10.1089/ind.2018.29121.mca. S. Cheng, L. Wei, X. Zhao, and J. Julson, “Application, deactivation, and regeneration of heterogeneous

catalysts in bio-oil upgrading,” Catalysts, vol. 6, no. 12, 2016, doi: 10.3390/catal6120195. A. K. Varma and P. Mondal, “Pyrolysis of sugarcane bagasse in semi batch reactor: Effects of process parameters on

product yields and characterization of products,” Ind. Crops Prod., vol. 95, pp. 704–717, 2017, doi: 10.1016/j.indcrop.2016.11.039.

RESULTS

Apunda E. Onyango1, B. E. Ndunda2, F. M. Mwazighe2 and F. Kimilu2

1Agriculture & Food Authority, Sugar Directorate, P.O. Box 51500-00200, Nairobi, Kenya2University of Nairobi, P. O. Box 30197-00100, Nairobi, Kenya

Proximate Analysis & Calorific Value of Bagasse & Bagasse Pellets (% Dry Mass)

Ultimate (elemental) Analysis of Bagasse & Bagasse Pellets (% Dry Mass)

Proximate Analysis

Proximate analysis is an essay of moisture, ash, volatile matter, and fixed carbon as determined by

prescribed test methods.

Moisture content is determined on the sample as received. On dry basis the moisture content is assumed

to be zero. Bagasse had a greater moisture % (as received) than bagasse pellets (6.94% against 5.79%).

Despite this fact, bagasse still had better combustion properties than the pellets.

Proximate analysis data on a dry matter basis indicate that fresh dried bagasse from the sugar factory

has less ash and more volatile matter than bagasse pellets from the pelleting plant. As a result, bagasse

from the sugar plant is more suited for both combustion and pyrolysis operations than bagasse pellets.

The bagasse pellets have high ash content but favorable amount of volatile matter and fixed carbon.

According to the proximate analysis data, both bagasse and bagasse pellets are suitable for combustion

and pyrolysis operations (for the production of bio-oil), but bagasse may perform better than bagasse

pellets. Bagasse is anticipated to generate more pyrolysis oil and have a greater calorific value than

bagasse pellets because of its high volatile matter concentration and low ash level.

A biomass with a high volatile matter % devolatilizes more readily and is more reactive than one with a

low volatile matter percentage [5] hence suitability for pyrolysis. High ash in biomass complicates the

thermochemical conversion process by lowering the rate of burning and raising the risk of fouling, slag

formation, and corrosion in pyrolysis reactors.

Calorific Value

The higher calorific value of fresh untreated dry bagasse compared to bagasse pellets is attributed to the

higher amounts of fixed carbon, volatile matter, and lower ash content.

Ultimate Elemental Analysis [CHNSO]

The ultimate analysis findings show that both bagasse and bagasse pellets contain low levels of Nitrogen

and Sulphur, indicating that an upgraded pyrolysis oil produced from sugarcane biomass will produce

extremely low levels of NOX and SOX gases, signifying a superior clean fuel than fossil fuels which

creates pollution to the environment through excessive discharge of NOX & SOX. The high O2 content of

biomass is often transmitted to the pyrolysis oil, resulting in unfavorable properties; this is an inherent

weakness for all lignocellulose biomass sources. Bagasse and bagasse pellets have good quality

characteristics in terms of carbon and hydrogen content when compared to other lignocellulose biomass.

Pyrolysis Experiment

A pyrolysis experiment was set up to evaluate the yield of pyrolysis oil from bagasse and bagasse pellets

feedstocks in order to verify the conclusions from proximal, ultimate, and heating value analytical data.

The pyrolysis oil output ranged from 42% - 46%. In general, bagasse feedstock yielded higher amount of

45.43% pyrolysis oil than bagasse 43.07% pellets.

Moisture

%

Volatile

Matter % Ash %

Fixed

Carbon %

Gross Calorific

Value (MJ/Kg)

Net Calorific

Value (MJ/Kg)

Bagasse - 85.57±0.58 3.31±0.03 11.12±0.58 22.15±0.02 20.88±0.02

Bagasse

Pellets - 81.82±0.34 7.26±0.10 10.91±0.34 18.69±0.02 17.44±0.02

Carbon % Hydrogen

%

Nitrogen

%

Sulphur

% Chlorine % Oxygen %

Bagasse 48.44±0.19 5.84±0.11 0.26±0.01 0.03±0.00 0.0153±0.0025 42.12±0.08

Bagasse

Pellets 46.50±0.35 5.70±0.15 0.27±0.03 0.02±0.00 0.0357±0.0016 40.25±0.53

44.25%

23.57%

32.51%

0.00%

5.00%

10.00%

15.00%

20.00%

25.00%

30.00%

35.00%

40.00%

45.00%

50.00%

Bio-oil Char Gas

% Y

ield

Pyrolysis Products

Yield of Pyrolysis Products

Run 1 2 3

% Yield 44.05% 46.21% 46.03%

Mean 45.43%

Run 1 2 3

% Yield 42.17% 43.36% 43.69%

Mean 43.07%

• Bagasse and its processed components have the potential to be used as a solid biofuel as well as in

the production of bio-oil through pyrolysis.

• Fresh untreated sugar factory bagasse has superior combustion characteristics and yields more

pyrolysis bio-oil than bagasse pellets.

• Bagasse is an abundant natural resource waste that may be recovered for the production of clean

green fuel with extremely low emissions of S and N pollutants into the environment.

This diagram depicts the experimental

setup for the fast pyrolysis experiment,

with pyrolysis oil as a main product.

Combustible gases and char are other

byproducts.

Approximately 800 g of dry bagasse

and 1500 g of bagasse pellets were fed

separately into a batch reactor

developed at UoN's Mechanical

Engineering department.

Yield of bio-oil, char & combustible

gases were determined.

Bagasse Bio-oil Yield

Bagasse Pellets Bio-oil Yield

Poster 10: Evaluation of Fuel Potential of Bagasse and Bagasse Pellets for

Thermo-chemical Processing into Clean Green Fuel