Combustion Characteristics of Macro and Micro Algae Biodiesel

Combustion Characteristics of Macro and Micro Algae Biodiesel

A.Ganesp , K. Gokula Kannan1

Student,

Department Mechanical Engineering, Sathiyabhama University, Chennai, India

Abstract: The interest on biodiesel research in India is mainly due to fluctuating crude prices, limited oil reserves and the strict emission standards. Here the experimental work has been carried out on a single cylinder, direct injection Diesel engine using Macro and Micro biodiesel blends under constant speed by varying the injection timings. The results show increased specific fuel consumption. The Brake thermal efficiency values of biodiesel are closer to Diesel. Compared to Diesel both the biodiesel blends give lesser un burnt hydrocarbons, Carbon monoxide and smoke emissions. Slight higher NOx emissions were found in Bio Diesel blends. While advancing the injection timing the performance and emission characteristics were good, compared to retarding it.

INTRODUCTION

At present, India is producing only 30% of the total petroleum fuels required. The remaining 70% is being imported. Biodiesel, an alternate of diesel, is defined as fatty acid methyl or ethyl esters from vegetable oils or animal fats. It is a renewable, biodegradable and oxygenated fuel .There are four methods normally used to convert oil and fats into bio diesel, they are direct use and blending, thermal cracking, transesterification, micro emulsion, out of which transesterification is the most popular method for making bio diesel from vegetable oil. Transesterification process is called as the chemical conversion of the oil to its fatty ester . In the Transesterification process, a catalyst (sodium hydroxide or potassium hydroxide) is used to split the oil molecules. An alcohol (methanol or ethanol) is used to combine with the separated esters. The byproduct from the reaction is glycerin. The viscosity of the end product is considerably reduced after the reaction. An alga has several advantages like being a potentially greener fuel feedstock and also it can be grown on nonarable areas. But still it struggles to find a place in the list of known biofuel crops. An alga is the preferred source because of its higher yield. The biomass can be doubled within 24hrs; the doubling time estimated was approximately 3.5hrs .The recent studies show that from the cultivation point of view, the algae are easy to cultivate, need very little or no

attention, less nutrients and the water which is unsuitable for human consumption can be used. Even though many reports explained the techniques about the conversion of algae oil in to biodiesel there are no or less reports gives the algae esters properties in comparison with diesel and almost no significant amount of work to explain the performance of it in a diesel engine. Many reports indicate Gracileria, Gelidium, kappaphycus etc are being cultivated in large scale in India for food and pharmaceutical applications. But only few of them have concentrated on biofuel from algae. There is lack of information regarding performance on a diesel engine using alga biodiesel. Therefore the main aim of this work is to extract the oil from an alga and to present the physical and chemical properties. The Performance, combustion, and emission characteristics of Esters of Algal oil are to be carefully investigated in a CI engine.

OIL EXTRACTION PROCESS

The Macro and Micro algae around 20 Kgs were collected from Central Marine Fisheries Research Institute, Chennai. The algae were shade dried for two days. The dried algae (5.5kg) powder was crushed in mortar and pestle with hexane and isoproponal solvent mixture (3/2 volume ratio). The extract was filtered and was allowed to stand in a separating funnel for a day; the top layer was taken and evaporated to remove the solvent. The resulting oil (1300 ml) was subjected to transesterification process. Transesterification of Algal Oil into Biodiesel.

Fig-1: Macro Algae

Fig 2: Micro Algae

Engine test

Table 1

TRANSESTERIFICATION OF ALGAL OIL INTO BIODIESEL

In this work sodium hydroxide is used as the catalyst, methanol is used as alcohol. The reaction is held between algal oil (the triglyceride), methanol and sodium hydroxide pellets at 65°C for 3hrs duration and the solution is stirred to ensure proper mixing. The reaction produces biodiesel and glycerol. The top layer is the required methyl esters and it is separated after filtering the glycerol, the methyl ester is then washed with water and the top layer is separated (850ml) and is then dried for property testing. The Properties of the biodiesel sample was tested by adapting ASTM testing protocols and are presented in Table 1.

100

80

60

40

20

0

-20

-40

The test was conducted at constant speed, four stroke, vertical, and air cooled Diesel engine. Two blends of algae biodiesel B10 and B20 were tested and the performance, combustion and emission parameters were taken. The loading is by means of an eddy current dynamometer.

Diesel macrob10

macrob20

-40 -20 0 20 40 60 80 100

CA vs HR (0% Load)

80

70

60

50

40

20

10

0

-10

-20

14

13

120

110

100

90

80

70

60

50

40

30

20

10

-20

-20

<>-10

0

160

140

120

100

80

60

40

20

0

30

-40 -20 0 20 40 60

CA vs HR (25% Load)

Diesel B10N50 B20N50

-40 -20 0 20 40 60 80 100

CA vs HR (50% Load)

Diesel

B10N10 0

B20N10 0

mic10N1 00

Biodiesel blends consume more fuel and the volumetric efficiency values for them are slightly lesser than Diesel. The advancement in the injection timing brought better results than other two injection timings. From the results we can conclude that the Rice bran oil and algae oil biodiesel blends (B20) can be a used modifying the Engine.

REFERENCES

1. Murugesan, A. Umarani, C. Subramanian,

   R. Nedunchezhian, N. (2009). Bio-diesel as an alternative fuel for diesel enginesA review, Renewable and Sustainable Energy Reviews 13,653662.

2. Jinlin Xue, Tony E. Grift, Alan C. Hansena (2011). Biodiesel Effect of biodiesel on engine performances and emissions, Renewable and Sustainable Energy Reviews 15 10981116.

3. Meher LC, Sagar DV, Naik S N (2006). Technical aspects of biodiesel production by Transesterification a review. Renew Sustain Energy Rev; 10:24868.

4. Oette K, Doss M. (1968) Mikromethode zur schnellen umesterung von lipoiden aufdünnschichtplatten mit natriummethylat für die gas-chromatographische analyse der fettsäuremethylester. J Chromatogr A; 32:43950.

5. Ma F, Hanna MA. Biodiesel production: a review. Biores Technol (1999); 70:115.

6. Dmytryshyn SL, Dalai AK, Chaudhari ST, Mishra HK, Reaney MJ. Synthesis and characterization of vegetable oil derived esters: evaluation for their diesel additive properties. Bioresour Technol 2004; 92:55 64.

7. Bala BK. (2005) Studies on biodiesels from transformation of vegetable oils for Diesel engines. Energy Edu Sci Techno; 15:143.

8. Demirbas A. (2003) Biodiesel fuels from vegetable oils via catalytic and noncatalytic supercritical alcohol transesterification and other methods: a survey. Energy Convers Manage 44:2093109.

-20 -40

Conclusion

10 60 110

CA vs HR (100% Load)

The performance and emission analysis of both the biodiesel fuel types shows that, they are better alternative to Diesel. Except NOX emission the other emission values are less compared to Diesel.