Biofuels Biomass Use of biofuels in electricity generation

Biofuels: Biomass - Use of biofuels in electricity generation, in transport, and in other energy consumption modes - Ecological impacts of biofuels and mitigation measures Prof. R. Shanthini 15 July 2019

What is biomass? Biomass consists of organic matter which typically comes from recently living organisms. The majority of biomass resources are composed of plant material or derived from plant material. These sources are regenerated constantly by plant growth. Therefore, biomass is a sustainable energy source Examples? ? ? Prof. R. Shanthini 15 July 2019 http: //renewables. morris. umn. edu/biomass/faq/

Conversion of Biomass into Useable Fuel: • Solid Fuel Combustion • Gasification • Pyrolysis • Hydrolysis / Fermentation / Digestion Prof. R. Shanthini 15 July 2019

What is Solid Fuel Combustion? Direct combustion of solid matter where the biomass is fed into a furnace where it is burned. The heat is used to boil water and the energy in the steam is used to turn turbines and generators. Prof. R. Shanthini 15 July 2019

Conversion of Biomass into Useable Fuel: Prof. R. Shanthini 15 July 2019

What is Gasification? - It is the partial burning of biomass (at high temperatures and limited oxygen) to create specific gases, generally referred to as "Producer Gas" (or "Synthesis Gas"), which is similar to natural gas. Prof. R. Shanthini 15 July 2019 http: //renewables. morris. umn. edu/biomass/faq/

Biomass gasification for electricity generation Prof. R. Shanthini 15 July 2019 http: //stlenergy. org/? attachment_id=461

Biomass gasification for electricity generation Prof. R. Shanthini 15 July 2019 http: //gasifiers. bioenergylists. org/beloniocfrh

Typical product composition from a gasifier : Prof. R. Shanthini 15 July 2019 http: //www 3. ul. ie/~childsp/Cin. A/Issue 58/TOC 14_Future. A. htm

What is Pyrolysis? Pyrolysis is the heating of an organic material (such as biomass) in the absence of oxygen. Because no oxygen is present the material does not combust but the chemical compounds (i. e. cellulose, hemicellulose and lignin) that make up that material thermally decompose into combustible gases and charcoal. Most of these combustible gases can be condensed into a combustible liquid, called pyrolysis oil (bio-oil), though there are some permanent gases (CO 2, CO, H 2, light hydrocarbons). Prof. R. Shanthini 15 July 2019 http: //www. ars. usda. gov/Main/docs. htm? docid=19898

What is Fast Pyrolysis? Fast pyrolysis is the rapid thermal decomposition of carbonaceous organic matter in the absence of oxygen. This process occurs at low pressure, moderate temperatures and in a very short amount of time. Fast pyrolysis produces three products: biochar, pyrolysis oil and non-condensable gases. Prof. R. Shanthini 15 July 2019

Fast Pyrolysis Prof. R. Shanthini 15 July 2019 http: //www. avellobioenergy. com/en/technology/fast_pyrolysis/

Fast Pyrolysis Yields are dependent on many factors including process conditions (reactor temperature, pressure, residence time) and feedstock composition. Optimal biomass processing conditions include: - reaction temperatures near 500°C - high heating rates - rapid cooling of the pyrolysis vapors after biochar has been sufficiently removed. Prof. R. Shanthini 15 July 2019

Pyrolysis Oil (or Bio-oil) is a dense complex mixture of organic compounds. It has a fuel value that is generally 50 – 70% that of petroleum bases fuels and can be used as boiler fuel or upgraded to renewable transportation fuels. It density is > 1 kg/L, much greater than that of biomass feedstocks, making it more cost effective to transport than biomass. Prof. R. Shanthini 15 July 2019 http: //www. ars. usda. gov/Main/docs. htm? docid=19898

Bio-char produced can be used on the farm as an excellent soil amender that can sequester carbon. Bio-char is highly absorbent and therefore increases the soil’s ability to retain water, nutrients and agricultural chemicals, preventing water contamination and soil erosion. Prof. R. Shanthini 15 July 2019 http: //www. ars. usda. gov/Main/docs. htm? docid=19898

Prof. R. Shanthini 15 July 2019 http: //eng. marmore. com. tr/marmore-pyrolysis-system

Phenol oil It is a potential product of pyrolysis. It is used to make wood adhesives, molded plastics and foam insulation. Wood adhesives are used to glue together plywood and other composite wood products. Prof. R. Shanthini 15 July 2019 http: //www. ars. usda. gov/Main/docs. htm? docid=19898

What is Hydrolysis/fermentation? Biomass can be converted directly into liquid fuels— biofuels — for our transportation needs (cars, trucks, buses, airplanes, and trains). The two most common types of bio-fuels are ethanol and bio -diesel. Ethanol is an alcohol, created by hydrolysis and fermentation of biomass high in carbohydrates. Bio-diesel is made by combining alcohol with vegetable oil, animal fat or other recycled cooking greases (no fermentation is involved here). Details on bioethanol and biodiesel are provided separately. Prof. R. Shanthini 15 July 2019

What is Digestion? Decomposition of organic matter by anaerobic bacteria in an oxygen-starved environment can produce methane. Anaerobic digesters compost (or “digest”) organic waste in a machine that limits access to oxygen, encouraging the generation of methane and carbon dioxide by microbes in the waste. This digester gas is then burned as fuel to make electricity. Prof. R. Shanthini 15 July 2019 http: //www. ars. usda. gov/Main/docs. htm? docid=19898

Economic Sustainability of Biomass Production The development of bio-energy markets can have many positive economic benefits including: - creating markets for biomass wastes, - improving the economic viability of thinning and harvesting operations - promoting new crops to farmers, especially on marginal or unused agricultural - creating employment in biomass production, harvesting, transport and conversion to useful energy - providing a saleable energy product. Prof. R. Shanthini 15 July 2019

How biomass reduces global warming? Biomass cycle Prof. R. Shanthini 15 July 2019

Life Cycle Analysis This analysis examines power generation from the following processes: Two fossil fuel based technologies: - coal-fired power production - natural gas combined-cycle (NGCC) Two biomass technologies: - biomass-fired integrated gasification combined cycle (IGCC) system using a biomass energy crop, - direct-fired biomass power plant using biomass residue Prof. R. Shanthini 15 July 2019

Prof. R. Shanthini 15 July 2019

Prof. R. Shanthini 15 July 2019

Prof. R. Shanthini 15 July 2019

List of Sustainability Indicators: - Conservation of biological diversity - Maintenance of productive capacity of forest ecosystems - Maintenance of forest ecosystem health and vitality - Conservation and maintenance of soil and water resources - Maintenance of forest contribution to global carbon cycles - Maintenance and enhancement of long-term multiple socioeconomic benefits to meet the needs of societies - Legal, institutional and economic framework for conservation and sustainable management Prof. R. Shanthini 15 July 2019

Environmental constraints Different biomass resources have different sustainability considerations: No sustainability constraints – Waste products – By-products – Forestry products – Dedicated cropping Multi sustainability constraints Prof. R. Shanthini 15 July 2019

What are the environmental impacts of bio-energy? Range of impacts both positive and negative that arise from use of bio-energy Focus on: Wood based fuels: • short rotation coppice (SRC) • short rotation forestry (SRF) • forest residues and low grade timber Not covering…. . Perennial grass crops; Conventional annual crops; Prof. R. Shanthini Waste 15 July 2019

What is short rotation coppice (SRC)? • Densely planted, high yielding varieties of either willow or poplar • Harvested on average every 2 -5 years • Expected lifespan of 15 -25 years (corresponding to around 6 harvests) • Shoots usually harvested during the winter as chips, short billets or as whole stems • Yields from SRC at first harvest range from 7 -12 tonnes dry weight/ha/yr Prof. R. Shanthini 15 July 2019

What are the environmental impacts of SRC? Threats Opportunities Landscape · change in landscape character · obscure landscape features · add structural diversity · restore and reinstate boundary features Biodiversity · displace open farmland · increase abundance/diversity bird species ground flora farmland bird · damage sensitive wetland species and invertebrates habitats · provide habitat for small mammals · buffer woodlands and vulnerable habitats Water · high water requirements · improve water quality · tackle nitrate pollution problems · treat wastewater Soil · soil compaction · reduce soil erosion and sedimentation problems Archaeology · damage archaeological sites and deposits Prof. R. Shanthini 15 July 2019

Management recommendations for SRC Do: Benefits: use mixed species biodiversity, landscape incorporate headlands, rides & open spaces biodiversity, landscape locate to minimise transport reduce CO 2 coppice cyclically biodiversity, landscape limit use of fertiliser, herbicides & pesticides biodiversity, water quality Don’t: Impacts: establish large monoculture blocks biodiversity, landscape replace land of high value for biodiversity plant in low rainfall areas or on waterlogged soils biodiversity block recreational access well-being plant on sites of archaeological interest heritage Prof. R. Shanthini 15 July 2019

What is short rotation forestry (SRF)? • Cultivation of fast-growing trees that reach their economically optimum size between 8 -20 years old • When felled - replaced by new planting or regenerate from stumps as coppice • Varieties may include native species such as alder, ash, birch, poplar, sycamore (cultivars), and nonnative species Prof. R. Shanthini 15 July 2019

What are the environmental impacts of SRF? Threats Opportunities Landscape · non native species - impact on landscape character · inappropriate in some open landscapes · creation of new native broadleaved woodland · expansion of existing woodland Biodiversity · trees with dense canopies – discourage ground feeding birds · displace birds adapted to open habitats · increase biodiversity if native species used · understorey vegetation can provide habitat for invertebrate and mammal species · increase abundance/diversity woodland birds Water · non-native species- high water requirements · lower inputs required – reduce nitrate pollution Soil · soil compaction during harvesting · stabilising impact - reduce soil erosion Archaeology · root growth - damage archaeological sites and deposits Prof. R. Shanthini 15 July 2019

Management recommendations for SRF Do: Benefits: incorporate 10 -20% of open space biodiversity, landscape leave some areas to mature to old age biodiversity maximise diversity of woodland structure biodiversity, landscape harvest cyclically biodiversity, landscape use UK Woodland Assurance Standard biodiversity, water quality Don’t: Impacts: plant in sensitive open landscapes biodiversity, landscape use non-native species biodiversity use exceptionally heavy equipment soil structure, water harvest forests on high carbon soils release CO 2 plant on sites of archaeological interest heritage Prof. R. Shanthini 15 July 2019

What are forest residues and low grade timber (LGT)? • Forest residues - harvesting residues (i. e. lop and top or brash) and small round wood (i. e. small stems of no commercial value) • Low grade timber - poor quality final crop and wood from unmanaged coppice Demand for wood fuel for bio energy has the potential to create an economic rationale for the re-introduction of traditional sustainable woodland management Prof. R. Shanthini 15 July 2019

What are the environmental impact of forest residues and LGT? Threats Opportunities Landscape · visual impact of new access tracks · perception of rapid changes to landscape · diversification of age structure of woodlands (reduce storm damage) · restoration of historic coppiced landscapes Biodiversity · depletion of nutrients · deprivation of food and habitat for small fungi and bats etc • • Prof. R. Shanthini 15 July 2019 diversification of woodland structure increase in edge and ride habitats increase in ground flora by reduction in shadiness thinning or felling of Plantations on Ancient Woodland Sites (PAWS) restoration of neglected coppice woodlands removal of invasive scrub and trees removal of rhododendron and other invasive species from open habitats

What are the environmental impact of forest residues and LGT? Threats Opportunities Water · increased runoff and impaired water quality · increased sedimentation of water courses Soil · damage to woodland soils · counter 20 th century increase · increased susceptibility to in nitrogen and potassium soil erosion after levels in soils harvesting · establishment ground cover – reduce soil erosion Archaeology · heavy machinery and creation of woodland tracks - damage to archaeological sites Prof. R. Shanthini 15 July 2019 • reduced risk of windblow disturbing remains

THE BIOMASS ENERGY SECTOR IN SRI LANKA • In developing countries, biomass fuel supplies approximately 35% of total primary energy, most of which is used traditionally for domestic cooking and space heating. • Traditional biomass accounts for nearly 52% of the primary energy supplied in Sri Lanka. • Nearly 76% of our population still depend on fuel wood and other forms of biomass for their household cooking Prof. R. Shanthini 15 July 2019

The Biomass Availability in Sri Lanka Prof. R. Shanthini 15 July 2019

Land Availability for Dendro Plantations Prof. R. Shanthini 15 July 2019

Projects undertaken in Sri Lanka Prof. R. Shanthini 15 July 2019

Prof. R. Shanthini 15 July 2019