Computational Engineering in Systems Applications (Volume II)
Vegetal Biomass, A Renewable Source for Obtaining of Clean Energy Matache M.1), VlăduŃ V.1), Danciu A.1), Voicea I.1), Pirnă I.1), Postelnicu E.1), Chirilă C.2) INMA Bucharest; 2)USAMV Iaşi Address: 6 Bd. Ion Ionescu de la Brad, Tel: +40 21 269.32.55; Fax: +40 21 269.32.73; Country: Romania E-mail:
[email protected] 1)
Abstract: In the paper was monitored highlighting the importance of vegetal biomass as raw material (renewable source) to obtain electricity and heat, by using products from its processing. Thus, using a pellets and agri-pellets production facility experiments were conducted using various vegetal materials as: straw, corncobs, Miscanthus, combined in different proportions with forest debris to identify the optimal proportions of materials that agri-pellets quality does not deteriorate . For each recipe was varied and the humidity of the mixture, finally resulting the maximum percentage of plant biomass that can be introduced in the mixture, so that the agri-pellets quality is not affected.
Key-Words: pellets, agri-pellets, renewable, moisture content, energy, biomass peas, cereal, energetic willow, rape, acacia, and buckwheat productivity rise [5, 6, 7]. It is considered that, in perspective, the energy produced by biomass will occupy the second place after the energy resulted out of fossil fuel burning. The role of biomass as a main source of food is primordial, but it is more and more regarded as a potential energy source, for the following reasons: - thermodynamic high value of available energy; - maintaining the natural circuit of CO2; - biosphere protection to pollution, virtually having a depolluting role; Chemical elements of biomass can be divided in two main categories: - main elements: cellulose, lignin, hemicellulose. These are common to all species of wood, disregarding variety or region; - secondary or particular elements: tannin, natural color mater, resins, oils, specific fats, sugar, carbon hydrates, and nitrogen based substances, mineral substances, and free organic acids. The main source of biomass is: energetic crops: eucalyptus, energy willow, poplar;
1 Introduction Promoting thermal and electrical energy production from renewable energy sources (RES) [1, 2, 9, 10, 11] in Romania and European Union, is an important factor in environment protection, economical independence to oil and natural gas imports, through diversifying energy supply sources, reducing greenhouse gas emissions and combating climatic change, using local energy sources, developing new business branches. The vegetal biomass is an important renewable energy source that can be used to obtain clean energy, without there being the problem of the raw materials which usually are depleted or being exhausted. An important source of biomass, both as a prime matter for different industries (construction materials, furniture and paper companies) as well as fire wood is represented by the forests (irrational exploited in areas from the country and abroad) having the negative effect of environment and climate change (due to erosion of deforested areas). Agricultural biomass is more appreciable in quantity than wood biomass, the high potential of biomass can be raised even more by a better use of existent resources and through sorghum, green
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Computational Engineering in Systems Applications (Volume II)
Agricultural solid biomass used for experimentation on different mixtures of agripellets was composed out if straws, miscanthus and cobs, and the forestry fraction used was of tree branches (sourcherry tree, poplar, apricot tree, etc.) grinded and fir woodchips. The experiment was established with 22 recipes: R1) forestry residue: 100% (two moisture content levels, one 12.46% and the second 22.6%); R2) woodchips: 100% (two moisture content levels, one 10.94% and the second 15.4%); R3) forestry residue: 33,33%; woodchips: 33.33% and cobs: 33.33% (mixture moisture content of 13.26%); R4) forestry residue: 33.33%; woodchips: 33.33% and straws: 33.33% (mixture moisture content of 12.61%); R5) forestry residue: 33.33%; woodchips: 33.33% miscanthus: 33.33% (mixture moisture content of 12.86%); R6) forestry residue: 65% miscanthus: 35% (two moisture content levels, one 13.64% and the second 15.15%); R7) forestry residue: 65 woodchips: 35% (two moisture content levels, one 12.67% and the second 15.15%); R8) woodchips: 65% and miscanthus: 35% (two moisture content levels, one 12.79% and the second 15.33%); R9) woodchips: 65% woodchips 35% (two moisture content levels, one 12,93% and the second 13.36%); R10) forestry residue: 60 miscanthus: 40% (two moisture content levels, one 12.13% and the second 15.04%); R11) forestry residue: 60% woodchips: 40% (two moisture content levels, one 12.38%, second 15.13%); R12) woodchips: 60% miscanthus: 40% (two moisture content levels, one 12.17% and the second 13.36%); R13) woodchips: 60% straws: 40% (two moisture content levels, one 12.54% and the second 15.36%); R14) forestry residue: 55% and miscanthus: 45% (two moisture content levels, one 11.31%, second 15.84%); R15) forestry residue: 55% straws: 45% (two moisture content levels, one 12.73% and the second 15.14%);
agricultural crops: sugar reed, rape, sugar beets; perennial crops: miscanthus, fast growing plants: switch grass and Panicum virgatum (perennial plant that grows in North America), Miscanthus or elephant grass (Ugandan grass). residues: wood from tree cutting and from material waste from constructions; straws and cereal stalks; other residues from food product processing (sugar reed, tea, coffee). waste: waste from wood processing, woodchips, sawdust; paper waste; municipal waste organic fraction; used vegetable oils and animal fats; mud from water treating stations; animal waste (manure). The technologies based on renewable energy have the great advantage that it uses the inexhaustible resources, very little pollution, with a negligible contribution to climate change. In addition, their use reduces dependence on conventional resources that will be exhausted in the not too distant future.
2. Problem Formulation In order to emphasize the importance of vegetal mass and its role as raw material for producing clean energy, several recipes of vegetal matters combined with forestry biomass have been experimented [8], modifying the humidity [4, 12, 13, 14] and using an installation of producing pellets and agri-pellets (fig. 1) of 120 kg/h capacity, comprising [3]: - scrap forest chopper type Skorpion; - chopper vegetable scraps TCU 22; - plant debris chopper TRV-0; - inclined conveyor with belt; - the crop residue homogenizer; - feeder press carrier; - refining device (hammer mill); - pelleting press.
Fig. 1. Installation for production of pellets and agripellets
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Computational Engineering in Systems Applications (Volume II)
Den Recipe (Mixture) [%] Mc Hm 3 No FR C M Sw Sk [%] [kg/m] 0 1 2 3 4 5 6
R16) woodchips: 55% miscanthus: 45% (two moisture content levels, one 12.44 and the second 14.96%); R17) woodchips: 55% straws: 45% (two moisture content levels, one 12.35% and the second 15.09%); R18) forestry residue: 50% and miscanthus: 50% (at a mixture moisture content of 15.78%); R19) forestry residue: 50% straws: 50% (at a mixture moisture content of 15.74%); R20) woodchips: 50% and miscanthus: 50% (at a mixture moisture content of 15.96%); R21) woodchips: 50% straws: 50% (at a mixture moisture content of 16.08%); R22) forestry residue: 43%; woodchips: 43% and cobs: 14% (at a mixture moisture content of 14.14%).
Obtained Pellets 7
-
- 10.94 554.26
4.
-
100 -
-
-
6.
43
43
-
15.4 411.13
-
8. 33.34 33.33 33.33 -
14 14.14 458.36
-
35
-
- 13.64 461.63
10. 65
-
35
-
- 15.15 409.19
11. 65
-
-
35
- 12.67 443.88
12. 65
-
-
35
- 15.15 404.09
13.
-
65 35
-
- 12.79 434.96
14.
-
65 35
-
- 15.33 364.00
15.
-
65
-
35
- 12.93 451.27
16.
-
65
-
35
- 13.36 408.36
17. 60
-
40
-
- 12.13 379.64
18. 60
-
40
-
- 15.04 386.15
19. 60
-
-
40
- 12.38 380.44
20. 60
-
-
40
- 14.89 389.36
21.
-
60 40
-
- 12.17 375.54
22.
-
60 40
-
- 15,13 394,16
23.
-
60
40
- 12,54 372,77
60
-
40
- 15.36 391.58
25. 55
-
45
-
- 11.31 379.15
26. 55
-
45
-
- 15.84 450.22
24.
-
-
-
-
- 12.46 508.36
Pellets have good density, quality product
2. 100
-
-
-
-
Moisture content is too high, pellets crumble
98
8 Pellets have good density, qualityproduct Pellets have good density, the quality suffered a slight drop
Agripellets obtained have a good density, quality product
- 12.86 483.34
65
9.
Observations
- 33,33 13.26 476.23
7. 33.34 33.33 - 33.33 - 12.61 491.91
8
-
ISBN: 978-1-61804-014-5
100 -
Observations
1. 100
22.6 351.29
-
5. 33.34 33.33 -
3. Problem Solution For every recipe the moisture content values where varied, between 10÷22%, in order to analyze behavior of the pellet machine and finally of the obtained pellets, according to moisture content (Fig. 2). The minimum moisture content of 10% was picked taking into consideration the forestry residue pellet producers, which recommend an optimal moisture content of 10÷12%. In our case – agripellet fabrication, the experiments began at a mixture moisture content value of 10% and were raised to approximately 22%, looking at the pellet machine behavior and the quality of agripellets obtained. Each recipe introduced in the technological flow of pellet and agripellet fabrication was of 10 kg, varying the proportions of forestry and agricultural biomass in the mixtures. Probe samples (biomass) from batch B were subjected to analysis in order to determine mixture moisture content and hectolitrical mass (Table 1): Table 1 The mixture moisture content of biomass and hectolitrical mass Den Recipe (Mixture) [%] Mc Hm 3 No FR C M Sw Sk [%] [kg/m] 0 1 2 3 4 5 6
3.
Obtained Pellets 7
Density of agripellets suffered a slight drop, acceptable quality
Density of agripellets suffered a slight drop, acceptable quality
Density of agripellets suffered a dramatic drop, lower moisture content doesn’t favor their quality Density of agripellets suffered adramaticdrop, but due to higher moisture content they have a better quality
Density of agripellets suffered a dramatic drop, lower moisture content doesn’t favor their quality
Density of agripellets suffered a dramatic drop, higher moisture content favors their quality Agripellet overall quality dramatically dropped as a result of addingtoomuch vegetal biomass, lower moisture content doesn’t favor their quality Agripellet overall quality dramatically dropped as a result of addingtoomuch vegetal
Computational Engineering in Systems Applications (Volume II)
Den Recipe (Mixture) [%] Mc Hm 3 No FR C M Sw Sk [%] [kg/m] 0 1 2 3 4 5 6
27. 55
-
-
45
- 12.73 394.56
28. 55
-
-
45
- 15.14 404.28
29.
-
55 45
30.
-
55 45
31.
-
55
32.
-
33. 50 34. 50
-
- 12.44 373.66
-
- 14.96 390.45
-
45
- 12.35 371.96
55
-
45
- 15.09 405.38
-
50
-
- 15.78 384.78
-
-
35.
-
50 50
36.
-
50
-
50
- 15.74 387.15
-
- 15.96 388.46
50
- 16.08 390.15
Obtained Pellets 7
Observations 8 biomass,highermoisture content led to a rise in their quality Agripellet overall quality dramatically dropped as a result of addingtoomuch vegetal biomass, lower moisture content doesn’t favor their quality Agripellet overall quality dramatically dropped as a result of addingtoomuch vegetal biomass,highermoisture content doesn’t favor their quality Agripellet overall quality dramatically dropped as a result of addingtoomuch vegetal biomass, lower moisture content doesn’t favor their quality Agripellet overall quality dramatically dropped as a result of addingtoomuch vegetal biomass,highermoisture content led to a rise in their quality Agripellet overall quality dramatically dropped as a result of addingtoomuch vegetal biomass, lower moisture content doesn’t favor their quality Agripellet overall quality dramatically dropped as a result of adding too much vegetalbiomass, higher moisturecontent led to a rise in their quality
References: [1] Biriş S., Paraschiv G., Maican E., Ungureanu N., Manea M., VlăduŃ V., Present and future in the field of alternative energy use, Scientific Papers - INMATEH, vol. I, 2009, pp. 13-22; [2] Biriş S., VlăduŃ V., Ungureanu N., Present and future in the field of alternative energy use in Romania, INTERNATIONAL CONFERENCE PROCEEDINGS "ENERGY EFFICIENCY AND AGRICULTURAL ENGINEERING", 2009, pp. 329-336; [3] Danciu A. and others, Experimentation of the equipments (plant debris chopper and conveyors) for processing agricultural and forestry solid biomass solids and the production technology for the pellets and agri-pellets, Research Report INMA Bucharest, 2010; [4] Danciu A., VlăduŃ V., Găgeanu P., Păun A., Lehr C., Possibilities of Reducing the Soil and Water Pollution Using Agricultural and Forestry Solid Biomass, Prospects for 3-rd millennium agriculture, Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, no. 66 (1 – 2), 2009, pp 44÷50; [5] Danciu A., VlăduŃ V., Voicea I., Postelnicu E., Possibilities of using solid biomass, agricultural and forestry for reducing pollution soil and water, Scientific papers INMATEH, vol. 1, 2009, pp 118-125; [6] Danciu A., Matache M.VlăduŃ V., Băjenaru S., Voicea I., The agricultural and forestry
Due to a high percentage of vegetal biomass, the quality of the agripellets is poor (they easily crumble)
Where: FR- forestry residue, C- chips; M- Miscanthus; Swstraws; Sk: stalks; Mc - Moisture content; Hm - Hectolitrical mass.
4. Conclusion As a result of experiments performed with the installation of obtaining pellets/agripellets using the 22 recipes of vegetal and forestry biomass mixture, the following have been found up: The agri-pellets quality is strongly influenced by the percentage of vegetal biomass out of the mixture and the mixture moisture content; While for pellets the high moisture content determined their low quality, in case of agri-
ISBN: 978-1-61804-014-5
pellets a higher moisture content up to 15.5% (max. 16%) is favorable to mixture cohesion and implicitly to a high quality of agri-pellets obtained; The agri-pellets quality is good at a percentage of mixture vegetal biomass of 40%, satisfactory at 45%, over this percentage the cohesion in the mixture being not suitably performed (determined by the insufficient quantity of lignin) and the obtained agri-pellets becoming breakable; Among the recipes of the agri-pellets obtained, those comprising miscanthus in their mixture are of better quality (they have a richer wooden mass).
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Medicine Cluj-Napoca - AGRICULTURE, no. 67 (1), 2010, pp 292-300.
solid biomass potential at national, regional and on areas level, International Symposium “Trends in European Agriculture Development” Scientific Papers, vol. 41(2), 2009, pp 385-396; [7] Danciu A., VlăduŃ V., ChiŃoiu M., Militaru M., Găgeanu P., Lehr C., Giving value to vegetal and forestry waste for agri-pellet production in agricultural farms, Journal Contemporary Agricultural Engineering, vol. 36, No. 4, 2010, pp 401-410; [8] Danciu A., VlăduŃ V., Matache M., Mihai M., Lehrl C., Mihailov N., Experimentation of manufacturing technology and equipments for pellets / agri-pellets, INMATEH - Agricultural Engineering, vol. 31, no. 2, 2010, pp 24-31; [9] Ion I., Ion D. (2006) - Energy from biomass, no .7 (38), Department of Termotechnics and Thermal Machines, University „Dunarea de Jos” of Galati; [10] Koppejan J., van Loo S. et al. (2002) Handbook of Biomass Combustion and Cofiring, IEA Bioenergy Task 32: Biomass Combustion and Cofiring. Twente University Press; [11] Nussbaumer Th. (2003) - Combustion and Co-combustion of Biomass: Fundamentals, Technologies, and Primary Measures for Emission Reduction. Energy Fuels. 17(6): 1510–1521; [12] Womac A.R., Igathinathane C., Sokhansanj S., Pordesimo L.O. (2005) Biomass moisture relations of an agricultural field residue: corn stover, Transactions of the ASAE. 48(6): 2073−2083, American Society of Agricultural Engineers, ISSN 0001−2351; [13] Singh R.N. (2004) - Equilibrium moisture content of biomass briquettes, Biomass and Bioenergy. 26: 251÷253, Thermochemical Conversion Division. Sardar Patel Renewable Energy Research Institute; [14] VlăduŃ V., ChiŃoiu M., Danciu A., Militaru M., Lehr C., The Importance of Moisture content on Agricultural and Forestry Biomass in the Process of Pellets and AgriPellets Production, Prospects for the 3-rd Millennium Agriculture, Bulletin of University of Agricultural Sciences and Veterinary
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