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End-of-Pipe Treatment Techniques
Published in Guttila Yugantha Jayasinghe, Shehani Sharadha Maheepala, Prabuddhi Chathurika Wijekoon, Green Productivity and Cleaner Production, 2020
Guttila Yugantha Jayasinghe, Shehani Sharadha Maheepala, Prabuddhi Chathurika Wijekoon
The addition of wood ash is encouraged as it acts as a source of some major elements such as potassium calcium, magnesium, etc. Alongside these major biodegradable waste constituents, the addition of the following materials will induce and speed up the process, as they act as catalysts. It is a pre-requisite to have at least one of these materials in small quantities. The catalyst materials include coffee pulp, animal manure (such as that of a chicken, goat, cow, sheep, or rabbit) and also dried blood, bone and fishmeal.
Rivers and Lakes: Acidification
Published in Brian D. Fath, Sven E. Jørgensen, Megan Cole, Managing Water Resources and Hydrological Systems, 2020
Agniezka Gałuszka, Zdzistaw M. Migaszewski
The Swedish Forest Agency has recommended that wood ash (received from timber waste combusted for energy production) should be used to mitigate acidification and to supplement nutrient removal.[98] In this method, the wood ash is added to the soil cover. Treatment of acidified waters is also possible with the use of ecotechnologies, such as constructed wetlands or controlled eutrophication.[99] The employment of these methods has many advantages. They are cost-effective, they are based on natural processes, and they can be applied to reduce acidification originating from non-point pollution sources (e.g., AMD).
Bioenergy technologies
Published in John Twidell, Renewable Energy Resources, 2021
The most vital aspect for the optimum combustion of any fuel is to control temperature and input of oxygen, usually as air. The aim with biomass and biofuel combustion, as with all fuels, is to have emissions with minimum particulates (unburnt and partially burnt material), with fully oxidized carbon to CO2 and not CO or CH4, and with minimum concentration of nitrogen oxides (usually resulting from excessive air temperature). Therefore, in practice, the combustion should be confined to a relatively small space at almost white-hot temperature; this volume has to be fed with air and fresh fuel. In addition, only fully burnt ash should remain; commonly known as ‘wood ash,’ its composition depends on the source material and combustion temperature, but in general it contains ∼40% CaCO3 and CaO, ∼10% potash, ∼0.7% phosphate and traces of metal oxides. Wood ash can be used, for example, for soil enhancement as a fertilizer and neutralizer of acidic soils, and, traditionally, for making soap. Useful heat is extracted by radiation from the combustion and by conduction from the flue gases through a steel heat exchanger, usually to water. Combustion of biofuels in engines, including turbines, has similar basic requirements, but occurs with much greater sophistication. Such combustion is optimized according to the circumstances, for example: With firewood: position the wood so that the fire is contained within a cavity of two or three burning surfaces, e.g. at the tips of three logs (the classic ‘three-stone fire’), or in the lengthwise space between three parallel logs.With wood chips or pellets: feed the fuel by conveyor or slope from a hopper to a relatively small combustion zone, onto which compressed air is blown and from which the ash falls.With general timber and forest waste: feed the fuel as above, but probably with a moving or shaking grate.With liquid and gaseous biofuels, the combustion should be controlled in boilers and engines as with liquid and gaseous fossil fuels, but with different air flow and fuel-/air-mixing requirements.
Wood bioash effect as lime replacement in the stabilisation of different clay subgrades
Published in International Journal of Pavement Engineering, 2020
Martina Zagvozda, Tatjana Rukavina, Sanja Dimter
Wood ash (WA) is a solid residue left behind by wood combustion (wood, sawdust, bark) in the production of energy, consisting mainly of inorganic substances and lower quantities of unburnt organic matter, moisture and gases (Vassilev et al.2013a). After Vassilev’s classification (Vassilev et al.2013a, 2013b), wood ashes in particular, are a C-type ashes, mainly consisting of CaO + MgO + MnO/carbonate, oxyhydroxides, glass, silicates and some phosphates and sulphates, and should exhibit cementitious binding properties. Minerals complementary to Portland cement that exhibit hydraulic and pozzolanic activity were also found by Ukrainczyk et al. (2016).
Performance evaluation of Nano wood ashes in asphalt binder and mixture
Published in International Journal of Pavement Engineering, 2022
Muhammad Ahsan Nisar, Syed Bilal Ahmed Zaidi, Ayyaz Fareed, Juan S. Carvajal-Munoz, Imtiaz Ahmed
Wood ash is a residue left after burning wood and its products (e.g. chip, sawdust, barks). Wood is burned when used as a fuel for energy production in thermal plants. Wood ash is also produced when the wood is set on fire for household activities. In Pakistan, wood is also utilised for fire production in furnaces such as brick furnaces. According to the Food and Agriculture Organization (FAO), burned biomass from forests produced in 2017 in Pakistan was approximately 161 thousand tonnes (Anon 2017).