Agri-pellets as alternative fuels for coal-fired power plants in Canada

Purpose Lignite coal-fired power plants are the main electricity generators in the province of Saskatchewan, Canada. Although burning lignite coal to generate power is economical, it produces significant greenhouse gases making it a big challenge to Canada’s international commitment on emission reduction. However, abundant agricultural crops and sawdust produced in Saskatchewan put the province in a good position to produce and use agri-pellets as an alternative fuel to generate electricity. This study aims to conduct an economic and environmental analysis of the replacement of lignite coal by agri-pellets as the fuel for Saskatchewan’s coal-fired power plants. Design/methodology/approach The study estimates the economic and environmental costs and benefits of two alternative fuels for power plants. The economic analysis is based on the pellet production and transportation costs from farms to production sites and from the production sites to power plants. In the production process, biomass precursors are densified with and without additives to produce fuel agri-pellets with appropriate mechanical durability and high heating value per volume unit. The environmental analysis involves estimation of greenhouse gas emissions and their social costs for lignite coal and different types of agri-pellets under different scenarios for pellet production and transportation. Findings The results show that although the total cost of electricity is lower for coal than agri-pellets, the gap shrinks when social costs and specifically a carbon price of $50/tonne are included in the model. The cost of electricity in lignite coal-fired power plants would also be on par with agri-pellets-fired power plants if the carbon price is between U$68 and $78 per tonne depending on the power plant locations. Therefore, a transition from coal to agri-pellet fuels is feasible if a high-enough price is assigned to carbon. The method and the results can be generalized to other places with similar conditions. Research limitations/implications There are a few caveats in this study as follows. First, the fixed costs associated with the transformation of the existing coal-fired power plants to pellet-fired plants are not considered. Second, the technological progress in the transportation sector, which would favor the net benefits of using pellets versus coal, is not included in the analysis. Finally, the study does not address the possible political challenges facing the transition in the context of the Canadian federal system. Practical implications The study results indicate that the current carbon price of $50 per tonne is not sufficient to make the agri-pellets a feasible source of alternative energy in Saskatchewan. However, if carbon pricing continues to rise by $15 annually starting in 2022, as announced, a transition from coal to agri-pellets will be economically feasible. Social implications Canada is committed to reduce its emission according to the Paris agreement, and therefore, needs to have a concrete policy to find alternative energy sources for its coal-fired power plants. This study examines the challenges and benefits of such transition using the existing agri-pellet resources in Saskatchewan, a province with abundant agricultural residues and coal-fired power plants. The findings indicate that a significant emission reduction can be achieved by using agri-pellets instead of coal to produce electricity. The study also implies that the transition to renewable energy is economical when social costs of carbon (carbon tax) is included in the analysis. Originality/value As far as the authors know, this is the first study providing a socio-economic analysis for a possible transition from the coal-fired power plants to a more clean and sustainable renewable energy source in one of the highest carbon dioxide (CO2) producer provinces in Canada: Saskatchewan. The study builds upon the technical production of three agri-pellets (oat hull, canola hull and sawdust) and estimates the economic and environmental costs of alternative fuels under different scenarios.

Effects of Microalgal Food Quantity on Several Productivity-Related Parameters of the Calanoid Copepod Bestiolina similis (Calanoida: Paracalanidae)

The optimization of copepod feeding protocol is paramount to improve culture productivity and to maintain favorable water quality parameters overtime, as well as saving operational costs by preventing the production of unnecessary quantities of microalgae. The influence of microalgal feeding concentration on major parameters related to culture productivity of the calanoid copepod Bestiolina similis (Paracalanidae) was investigated in a series of laboratory experiments. B. similis was fed eight different concentrations (0, 150, 300, 600, 900, 1,200, 1,500 and 1,800 μgC l–1) of a mixed microalgal diet consisting of Tahitian strain of Isochrysis species, Pavalova 50 and Tetraselmis chuii at 1:1:1 carbon ratio. The results indicate that female daily and cumulative egg production over lifespan, egg hatching rate, naupliar and copepodite survival and development, adult female life expectancy, population growth and fecal pellet production rate (FPPR) were all significantly affected by microalgae feeding ration. Conversely, no significant influence could be established between microalgae food concentration and egg diameter or adult sex ratio. Feeding rations as low as 150 μgC l–1 led to lower egg hatching rates, survival and development, adult female life expectancy and population growth compared with the higher microalgae rations tested. Feeding concentration ≤ 900 μgC l–1 significantly limited female daily egg and fecal pellet production rate, as well as their cumulative egg production over lifespan, when compared to a level of 900 μgC l–1. Bestiolina similis fed with 1,200 μgC l–1 significantly improved female egg and fecal pellet production when compared to the lower treatments and was responsible for the highest female lifespan egg production and population growth observed among all treatments. Feeding rations as high as 1,500 μgC l–1 and 1,800 μgC l–1 did not lead to significant improvement in any of the parameters measured. This is likely due to a saturation effect at high food concentration which is known to decrease calanoid copepods feeding efficiency. Finally, B. similis FPPR, used as a proxy for ingestion, was found to saturate at a microalgae concentration of 783.4 μgC l–1 using a non-linear Michael-Menton (2 parameters), indicating that CVI female ingestion did not increase significantly above this concentration. Based on the above results it is recommended that B. similis cultures should be fed at a concentration of 1,200 μgC l–1, and not above, as rations > 1,200 μgC l–1 will not significantly improve any of the productivity-related parameters observed in this study. Feeding rations should never be below 783.40 μgC l–1 as this is the threshold level below which adult female ingestion rates become limiting.

Life Cycle Assessment of Wood Pellet Product at Korintiga Hutani company, Central Kalimantan, Indonesia

Climate change has forced human being to adapt in fulfilling their energy needs sustainably. In Indonesia, forestry activities has been considered as an emission rather than carbon sink. This study aims to analyze the inputs, outputs, and potential environmental impacts of wood pellet production in a forest company using life cycle assessment (LCA). The wood pellet is made from Eucalyptus pellita plantation. Analysis was made for 1 planting cycle or 6 years, and allometric equations were used to estimate the ability of industrial timber plantation forest to absorb CO2. Production of wood pellet starting from plantation requires inputs as follows: diesel fuel, electricity, NPK and other fertilizers, pesticides, and electrical energy. Those inputs produced emissions, of which the largest was N2O of 551.2927 kg, followed by NH3 of 7.5275 kg generated from NPK fertilizer. Another was PO43- amounted at 0.1792–0.2229 kg from liquid fertilizers and pesticides. Potential acidification came from 13.3675 kg SO2 eq, and eutrophication of 0.4021 kg PO43- eq. The greenhouse gas (GHG) emission was 678.0270 kg CO2 eq from the plantation activities, especially from diesel-based energy consumption, while wood pellet mills only released 0.1053 kg CO2 eq of GHG emissions. Thus, total emissions from 6 years' time of wood pellet production are much lower compared to the average CO2 absorbed by the plantation forest, of which annually is 36.34–67.69 ton ha-1year-1.

Spruce and Barley Elemental and Stochiometric Analysis Affected by the Impact of Pellet Production and Torrefaction

Biomass is a potential biofuel which may help fighting high carbon dioxide emissions and negative impacts of global warming. Analysis of Norway spruce (Picea abies) and barley (Hordeum vulgare) were performed at the laboratory of Czech University of Life Sciences. Material was torrefied in an inert nitrogen atmosphere at the temperatures of 250 °C and 280 °C for 45 minutes. Elementary and stoichiometric parameters were monitored and impact of torrefaction and pellet production on carbon footprint was determined. Torrefied and pelleted material showed better fuel properties in comparison to the original material. Calorific value of the torrefied spruce wood chip increased by 12.27% when torrefied at the temperature of 250 °C, and by 25.41% when torrefied at the temperature of 280 °C.

Deodorizing Methods for Recycled High-density Polyethylene Plastic Wastes

The recycling of high-density polyethylene plastic (HDPE) plays a crucial role in sustainable development. However, obstacles to the use of recycled HDPE remain because of the material and processing properties and odors of recycled HDPE. The odor of recycled detergent bottle plastic leads to rejection by most detergent manufacturers. Recently, some recycling enterprises have adapted recycling with odor reduction processes involving the use of solvents, antimicrobial additives, and odor extraction units in feeders and extruders. However, these processes may affect the quality and cost of recycled plastic. Most small and medium businesses (SMBs) may not favor these effects due to their limited models and resources. In addition, most SMBs are unwilling to replace their current recycling operation units. Hence, this study aimed to find alternative and economical ways for odor reduction in the recycling process. A modification of the recycling process was introduced in the pretreatment of plastic flakes before entry into the feeder of an extrusion unit. The effect of selected washing temperatures, i.e., 65℃, 75℃, 85℃, and 95℃, on the removal of odor from recycled HDPE was further studied. The addition of sodium bicarbonate, calcium carbonate, and citric acid into a heated water bath enhanced the deodorizing effect. The relationship of these three chemicals with the deodorization of HDPE plastics was investigated through sensory evaluation. Lastly, the potential of the deodorized recycled HDPE for resin pellet production and commercialization were investigated.

PENGARUH CAMPURAN TANAH GAMBUT DAN PUPUK KANDANG AYAM TERHADAP PERTUMBUHAN Caliandra callothyrsus

Kaliandra (Calliandra callothyrsus) is a plant that includes of Fabaceae family. Kaliandra has 200 species in a medium-sized tree with compounded flowers. benefits of Kaliandra can produce fast and qualified raw materials energy, especially for pellet production. Producing Energy is for commercial requirements about 4600 kcal per kg of dry wood and 7200 kcal per kg of charcoal. This research purpose is to get the best media in Kaliandra growth. The method of research has been used by Completely Randomized Design (CRD). The research consisted of 6 treatments of planting media (M0, M1, M2, M3, M4, M5). Those treatments have been 5th replicated therefore become 30 experimental units. These results showed best media is M5 (peat soil: Chicken Manure = 3:1). M5 is the best plant growth media.Keywords: Calliandra growth at peat media AbstrakKaliandra (Caliandra callothyrsus) merupakan tanaman anggota family Fabaceae. Kaliandra memiliki anggota sekitar 200 jenis wujudnya berupa pohon berukuran sedang dengan bunga tersusun majemuk. Manfaat dari Kaliandra dapat menghasilkan bahan baku energi secara cepat dan berkualitas terutama untuk produksi pelet. Energi dihasilkan untuk syarat komersial sekitar 4600 kkal per kg kayu kering dan 7200 kkal panas per kg arang. Penelitian ini bertujuan untuk mendapatkan media terbaik dalam pertumbuhan Kaliandra. Metode yang digunakan adalah eksperimen dirancang menggunakan Rancangan Acak Lengkap (RAL). Percobaan terdiri dari 6 perlakuan media tanam (M0, M1, M2, M3, M4, M5). Penelitian ini menggunakan 5 kali ulangan sehingga terdapat 30 unit percobaan. Hasil penelitian menunjukan bahwa media terbaik adalah M5(Tanah gambut: Pupuk kandang ayam = 3:1). Media M5 merupakan media dengan pertumbuhan tanaman terbaik.Kata kunci: Pertumbuhan kaliandra pada media gambut