Straw Residual Potential in Serbia for Energy Use -taking into - PowerPoint PPT Presentation

Workshop “Straw-Combustion - Economic Opportunities for the Serbian Agro- Industry” Belgrade, 22 nd April 2015 Straw Residual Potential in Serbia for Energy Use -taking into account the soil balance, economic aspects and technical requirements on the supply chain- Martinov, M., Djatkov, Dj., Golub, M., Viskovic, M. Faculty of Technical Sciences, Novi Sad 1

OUTLINE 1. INTRODUCTION 2. POTENTIALS OF BIOMASS IN SERBIA 3. OWN INVESTIGATIONS 4. PROCUREMENT, SUPPLY CHAINS, COSTS 5. SUSTAINABILITY ISSUES 6. CONCLUDING ISSUES 2

1. INTRODUCTION STAGES OF TECHNOLOGY MATURITY 1. Laboratory level, tests positive. 2. Prototype level, confirmed results. 3. Demonstration plant level, approved results. 4. Commercial level (even better few years tested in practice). FOR SERBIA IS ACCEPTABLE ONLY THE FOURTH ONE!!! 3

September 2014 October 2014 4

Some examples of crop residues use 5

Examples of contemporary heat generators produced in Serbia 6

Many open questions: 1. Mature biofuel technology? 2. Realistic feedstock potential based on sustainable approach, soil fertility preservation? 3. Proper harvest and storage technology of corn stover? 4. Costs of feedstock? 5. Supply security? 6. Environmental impact, including GHG reduction? 7. Etc. 7

2. POTENTIALS OF BIOMASS IN SERBIA Source Biomass Hydro Solar Geothermal Wind Σ % 62 14 15 5 4 100 Мtое 3.3 1.7 0.6 0.2 0.2 6.0 (0.8+0.9) Source: National renewable energy action plan of the Republic of Serbia, 2013 8

We consider following potentials: 1. Theoretical. 2. Harvestable (technical). 3. Sustainable. 4. For energy. 5. Specific for large consumers due to use of big bales, plots over 5 ha. 9

According to our calculations, potentials of crop residues are lower, about 1.3 M toe Sustainable Energy potential, Big S&M Acreage, potential, 1,000 t 1,000 t Crop T farms, farms, 1,000 ha S&M S&M 1,000 t 1,000 t Big farms Big farms farms farms Wheat  797 178 619 374 1,080 355 970 Ray ─ 8.6 0.8 7.8 2 14 2 14 Barley ─ 135 46.6 88.4 80 154 80 138 s 130 s 735 s 130 s 660  Corn 1,358 133 1,225 c 15 c 1,200 c 15 c 1,200 Sunflower ─ 160 74.9 85.1 0 0 0 0 Soybean  83 54.8 28,2 105 50 105 50 Oil rape  1.4 0.7 0.7 2 2 2 2 708 3,235 689 3,034 Total 3,943 3,723 T– trend of growing acreage, S&M– small and medium farms, s– stover (for the S&M not calculated harvest of on field remained mass, only if universal harvester is used), c– cobs (harvest with picker-husker, typical for S&M farms and seed production) 10

2. OWN INVESTIGATIONS For each crop were taken samples, total above ground mass, from three different locations, five per plot, in the full maturity of grain, harvest time in 2011 and 2012. Weather conditions in 2011 were identified, as very dry, although such definition is common for the last decade. In 2012 they were extremely dry. The plants were separated into fractions as further described, moisture content measured, mass of fractions, and their relative yield (relative to grain yield) and harvest index calculated. The residual mass that is expected to be harvested, depending on harvest procedure, is assigned as harvestable mass . On field remained mass of crop residues is calculated by subtracting harvestable from total mass of above ground residues. The criterion for erosion protection was the amount of on field remained biomass. It should cover at least 30 % of surface, i.e. 1.1 Mg of flat small grain residue equivalent ASAE EP291.3 (Anonymous, 2005). Tillage losses and weathering impact were calculated based on Hickman and Schoenberger (1989) procedure. 11

Corn Harvest, typically, starts in the second half of September, for hybrids of FAO group 400, and finishes at the end of November, for the hybrids of FAO group 700. The samples were taken on farms that apply high level of agro technology. The row distance on all plots was 0.7 m, and crop density 60,000 to 70,000 plants per ha, as common in the region. 12

The calculation of harvestable mass is performed based on harvest procedures, described in Golub et al. (2012). This includes harvested fractions and harvest losses. Single-pass procedure, described by some authors, is followed by productivity reduction up to 50 % (Shinners et al., 2012). The stover harvest procedures and assumed losses are: Two-pass harvest. Grain harvest by combine with snapper–head and integrated shredder-cornrower described in Straeter (2011) and Shinners et al. (2012). The stover is picked-up from windrow by round or big rectangular baler. Cutting height is 0.2 m. Percentages of harvested fractions are 70, 90 and 90 %, for stalks+leaves, cobs and husks respectively, with additional baling losses of 20 %. Multi-pass harvest. This is conventional stover harvest procedure. As previous but combine harvester is equipped with integrated stover shredder. It is followed by raking, forming windrow and baling. The cutting height is 0.2 m. Percentages of harvested fractions are 70 % for stalks+leaves and 40 % for cobs and husks combined, with additional baling losses of 20 %. Ears harvest. For the harvest is used picker-husker. All cobs are available after natural drying and threshing in yard, without losses. 13

Wheat and soybean The samples of eight varieties of wheat and six of soybean were collected. Based on the results for moisture content, yield of each part of the plant was calculated. Diagrams representing cumulative mass of stalks along its height were made. These diagrams were used for determination of stalks residues remaining on a field after harvest, stubble, depending on cutting height. Wheat and soybean straw segments 14

Range and average of relative yields of stover fractions, 1 – lowest 0.2 m of stalks, 2 – stalk+leaves, 3 – cobs, 4 – husks, 5 – total aboveground residues, 6 – sum of 2, 3 and 4 2011 Corn Harvestable mass Remained Harvest mass proc. RY, % Mg ha –1 PTM, % Mg ha –1 1 51 5.5 53 4.8 4.5 2011 2 41 43 5.6 2012 3 18 1.9 19 8.4 1 72 3.8 53 3.3 3.1 2012 2 59 43 4.0 High dissipation 3 22 1.1 16 6.0 RY – relative yield (to grain) PTM – percentage of total above ground mass 15 15

For both seasons, the percentage of harvestable mass related to total was same for the harvest procedures 1 and 2, 53 and 43 % respectively, but harvestable mass considerably lower, 5.5/3.8 and 4.5/3.1 Mg ha – 1 . Reduction of harvestable mass was, due to weather conditions, 31, 31 and 42 %, and on field remained mass 29, 32 and 28 %, for harvest procedures 1, 2 and 3, respectively. In all cases the on field remained residual biomass can ensure, by using of adequate tillage, wind erosion protection! The obtained data can be used for solving some of defined problems! 16

Wheat , cutting height 15 cm Soybean , cutting height 7.5 cm Parameter 2011 2012 Parameter 2011 2012 Grain yield, Mg ha – 1 6.9 5.1 Grain yield, Mg ha – 1 4.7 2.7 Harvest index 0.48 0.49 Harvest index 0.47 0.41 Mass of aboveground residues, Mg ha – 1 7.6 5.2 Mass of aboveground residues, Mg ha – 1 5.3 3.8 3.8 2.1 2.1 1.3 Mass of harvestable straw, Mg ha – 1 Harvestable mass*, Mg ha – 1 Percentage of harvestable mass in Percentage of harvestable mass in 55.5 40.0 44.7 48.1 comparison with mass of grain*, % comparison to mass of grain*, % Percentage of harvestable mass in Percentage of harvestable mass in 50.0 39.3 39.6 34.2 aboveground residues, % aboveground harvest residues, % On field remained mass, Mg ha – 1 3.8 3.1 On field remained mass, Mg ha – 1 3.2 2.5 Percentage of on field remained mass in Percentage of on field remained mass in 50.0 60.7 60.4 65.8 aboveground residues, % aboveground residues, % Mg is correct, according to IS, designation for tone 17

Decrease of harvestable straw mass for wheat was 45 %, and on field remained mass 18 %. For soybean harvestable straw mass decreased 37 %, and on filed remained mass 20 %. On field remained mass of crop residues after application of chisel ploughing Crop Soybean Wheat Season 2011 2012 2011 2012 On field remained 2.1 1.7 2.5 2.1 mass DM, Mg ha –1 18

ONGOING R&D ACTIVITIES 1. Experimental determination of biogas yield and methane potential BG yield= 387.8 ml/gDM (SD=15.4) BG yield= 406.5 ml/gODM (SD=16.1) CH4 = 187.4 ml/gDM (SD=11.8) CH4 = 196.4 ml/gODM (SD=12.4) CH4 = 48.3 % (SD=1.3 %) Good yield, too long retention time! 2. Improvement of corn stover harvest and storage 3. Development of corn stover pelletizing 19 19

4. PROCUREMENT, SUPPLY CHAINS, COSTS Procurement, provision, consists of: 1. Harvest, collection, of crop residues on the field. 2. Loading of feedstock to the transport vehicle. 3. Transport to the primary storage. 4. Unloading and storing. For the bigger users there are additional activities: 5. Loading to the long distance vehicle. 6. Transport to the plant storage. 7. Unloading and storing. 8. Exemption from storage, pre processing, feeding the plant. Simplified it can be split into harvest and logistic. 20

Straw harvest and logistic solved grains grain combine harvester corn silage straw bales bales storage swat drying self propelled mower grinded material low storage forage harvester bales bales storage self propelled straw harvester pellets pellets silage or floor storage self propelled pellet mashine 21