Biomass Energy and Sustainability

Biomass energy systems offer significant possibilities for reducing greenhouse gas emissions due to their immense potential to replace fossil fuels in energy production. Biomass reduces emissions and enhances carbon sequestration since short-rotation crops or forests established on abandoned agricultural land accumulate carbon in the soil. Biomass energy usually provides an irreversible mitigation effect by reducing carbon dioxide at source, but it may emit more carbon per unit of energy than fossil fuels unless biomass fuels are produced in a sustainable manner.

Biomass resources can play a major role in reducing the reliance on fossil fuels by making use of thermo-chemical conversion technologies. In addition, the increased utilization of biomass-based fuels will be instrumental in safeguarding the environment, generation of new job opportunities, sustainable development and health improvements in rural areas.

biomass-sustainability

The development of efficient biomass handling technology, improvement of agro-forestry systems and establishment of small and large-scale biomass-based power plants can play a major role in sustainable development of rural as well as urban areas. Biomass energy could also aid in modernizing the agricultural economy and creating significant job opportunities.

Harvesting practices remove only a small portion of branches and tops leaving sufficient biomass to conserve organic matter and nutrients. Moreover, the ash obtained after combustion of biomass compensates for nutrient losses by fertilizing the soil periodically in natural forests as well as fields.

The impact of forest biomass utilization on the ecology and biodiversity has been found to be insignificant. Infact, forest residues are environmentally beneficial because of their potential to replace fossil fuels as an energy source.

A quick glance at popular biomass resources

A quick glance at popular biomass resources

Plantation of energy crops on abandoned agricultural land will lead to an increase in species diversity. The creation of structurally and species diverse forests helps in reducing the impacts of insects, diseases and weeds. Similarly the artificial creation of diversity is essential when genetically modified or genetically identical species are being planted.

Short-rotation crops give higher yields than forests so smaller tracts are needed to produce biomass which results in the reduction of area under intensive forest management. An intelligent approach in forest management will go a long way in the realization of sustainability goals.

Improvements in agricultural practices promises to increased biomass yields, reductions in cultivation costs, and improved environmental quality. Extensive research in the fields of plant genetics, analytical techniques, remote sensing and geographic information systems (GIS) will immensely help in increasing the energy potential of biomass feedstock.

A large amount of energy is expended in the cultivation and processing of crops like sugarcane, coconut, and rice which can met by utilizing energy-rich residues for electricity production. The integration of biomass-fueled gasifiers in coal-fired power stations would be advantageous in terms of improved flexibility in response to fluctuations in biomass availability and lower investment costs. The growth of the biomass energy industry can also be achieved by laying more stress on green power marketing.

The Technology Revolutionizing Commercial Waste Management

Every single one of us can do something to improve our impact on the planet, but it is a given that businesses of all sizes have a bigger footprint than families – commercial accounts for 12% of total greenhouse gas emissions. A big factor of that is waste management. From the physical process of picking up garbage, to the methane-released process of decomposition, there are numerous factors that add up to create a large carbon footprint.

Between hiring green focused waste management solutions and recycling in a diligent fashion, there are a few technologies that are helping to break down the barrier between commercial waste management and an environmentally positive working environment.

Cleaning up commercial kitchens

A key form of commercial waste is food waste. Between the home and restaurant, it is estimated by the US Department of Agriculture that 133 billion pounds of food is wasted every year. Much will end up in the landfill. How is technology helping to tackle this huge source of environmental waste? Restaurants themselves are benefiting from lower priced and higher quality commercial kitchen cooking equipment, that helps to raise standards and reduce wastage.

Culinary appliances for varied cuisines also benefit from a new process being developed at the Netherland’s Wageningen University. A major driver of food waste is rejected wholesale delivery, much of which will be disposed of in landfill. The technology being developed in Holland aims to reduce wastage by analyzing food at the source, closer to where recycling will be achievable.

Route optimization

Have you ever received a parcel from an online retailer only to find the box greatly outsizes the contents? On the face of it, this is damaging to the environment. However, many retailers use complex box sorting algorithms. The result is that the best route is chosen on balance, considering the gas needed to make the journey, the amount of stock that can be delivered and the shortest route for the driver. This is an area of intense technological innovation.

The National Waste & Recycling Association reported in 2017 on how 2018 would see further advances, particularly with the integration of artificial intelligence and augmented reality into the route-finding process.

Balancing the landfill carbon footprint

It is well established that landfills are now being used to power wind turbines, geothermal style electricity and so on. They are being improved to minimize the leachate into groundwater systems and to prevent methane escaping into the atmosphere. However, further investigation is being pushed into the possibility of using landfill as a carbon sequester.

AI-based waste management systems can help in route optimization and waste disposal

Penn State University, Lawrence Berkeley and Texas University recently joined together to secure a $2.5m grant into looking into the function of carbon, post-sequestration. This will help to shed light on the carbon footprint and create a solid foundation on which future technology can thrive.

Businesses of all sizes have an impact on the carbon footprint of the world. The various processes that go into making a business profitable and have a positive impact on their local and wider communities need to be addressed. As with many walks of life, technology is helping to bridge the gap.

Overview of Biomass Pyrolysis Process

Biomass pyrolysis is the thermal decomposition of biomass occurring in the absence of oxygen. It is the fundamental chemical reaction that is the precursor of both the combustion and gasification processes and occurs naturally in the first two seconds. The products of biomass pyrolysis include biochar, bio-oil and gases including methane, hydrogen, carbon monoxide, and carbon dioxide.

The biomass pyrolysis process consists of both simultaneous and successive reactions when organic material is heated in a non-reactive atmosphere. Thermal decomposition of organic components in biomass starts at 350 °C–550 °C and goes up to 700 °C–800 °C in the absence of air/oxygen. The long chains of carbon, hydrogen and oxygen compounds in biomass break down into smaller molecules in the form of gases, condensable vapours (tars and oils) and solid charcoal under pyrolysis conditions. Rate and extent of decomposition of each of these components depends on the process parameters of the reactor temperature, biomass heating rate, pressure, reactor configuration, feedstock etc

Depending on the thermal environment and the final temperature, pyrolysis will yield mainly biochar at low temperatures, less than 450 0C, when the heating rate is quite slow, and mainly gases at high temperatures, greater than 800 0C, with rapid heating rates. At an intermediate temperature and under relatively high heating rates, the main product is bio-oil.

Slow and Fast Pyrolysis

Pyrolysis processes can be categorized as slow or fast. Slow pyrolysis takes several hours to complete and results in biochar as the main product. On the other hand, fast pyrolysis yields 60% bio-oil and takes seconds for complete pyrolysis. In addition, it gives 20% biochar and 20% syngas.  Fast pyrolysis is currently the most widely used pyrolysis system.

The essential features of a fast pyrolysis process are:

  • Very high heating and heat transfer rates, which require a finely ground feed.
  • Carefully controlled reaction temperature of around 500oC in the vapour phase
  •  Residence time of pyrolysis vapours in the reactor less than 1 sec
  • Quenching (rapid cooling) of the pyrolysis vapours to give the bio-oil product.

Advantages of Biomass Pyrolysis

Pyrolysis can be performed at relatively small scale and at remote locations which enhance energy density of the biomass resource and reduce transport and handling costs.  Heat transfer is a critical area in pyrolysis as the pyrolysis process is endothermic and sufficient heat transfer surface has to be provided to meet process heat needs. Biomass pyrolysis offers a flexible and attractive way of converting organic matter into energy products which can be successfully used for the production of heat, power and chemicals.

A wide range of biomass feedstock can be used in pyrolysis processes. The pyrolysis process is very dependent on the moisture content of the feedstock, which should be around 10%. At higher moisture contents, high levels of water are produced and at lower levels there is a risk that the process only produces dust instead of oil. High-moisture waste streams, such as sludge and meat processing wastes, require drying before subjecting to pyrolysis.

Furthermore, the bio-char produced can be used on the farm as an excellent soil amender as it is highly absorbent and therefore increases the soil’s ability to retain water, nutrients and agricultural chemicals, preventing water contamination and soil erosion. Soil application of bio-char may enhance both soil quality and be an effective means of sequestering large amounts of carbon, thereby helping to mitigate global climate change through carbon sequestration.  Use of bio-char as a soil amendment will offset many of the problems associated with removing crop residues from the land.

Biomass pyrolysis has been garnering much attention due to its high efficiency and good environmental performance characteristics. It also provides an opportunity for the processing of agricultural residues, wood wastes and municipal solid waste into clean energy. In addition, biochar sequestration could make a big difference in the fossil fuel emissions worldwide and act as a major player in the global carbon market with its robust, clean and simple production technology.