Dry dung fuel (or dry manure fuel) is animal feces that has been dried in order to be used as a fuel source. It is used in many countries. Using dry manure as a fuel source is an example of reuse of excreta. A disadvantage of using this kind of fuel is increased air pollution. [1]
Dry dung is more commonly used than moist dung, because it burns more easily. Dry manure is typically defined as having a moisture content less than 30 percent. [2]
"Dung cakes", made from the by-products of animal husbandry, are traditionally used as fuel in India for cooking food in a domestic hearth called a Chulha. They are made by hand by village women and are traditionally made from cow or buffalo dung. One dung cake of an average size gives 2100 kJ worth of energy. Dung cakes are also known as goitha, uple, kande, gosse or thepdi.
These are the cakes of cow dung molded by bare hands with a curvature to be able to keep stuck to the walls. Once dried they are put in a pile and covered with thatch called bitauda. These bitaudas are visible in parts of rural India albeit with different names. The size and shape of the cake might vary with region. Its also not uncommon to see these cakes directly used in earthen ovens.
This biofuel has been used primarily for two reasons: for easy disposal of cow dung and as easily available and cheap fuel.
Human feces can in principle also be dried and used as a fuel source if they are collected in a type of dry toilet, for example an incinerating toilet. Since 2011, the Bill & Melinda Gates Foundation is supporting the development of such toilets as part of their "Reinvent the Toilet Challenge" to promote safer, more effective ways to treat human excreta. [3] The omni-processor is another example of using human feces contained in fecal sludge or sewage sludge as a fuel source.
Some aspects of using dry animal dung include: [4]
Also, camel dung is used as fuel in Egypt.
Dry animal dung was used from prehistoric times, [14] including in Ancient Persia, [10] Ancient Egypt and early modern England. [15] In Equatorial Guinea archaeological evidence has been found of the practice [16] and biblical records indicate animal and human dung were used as fuel. [17]
The combustion of dried dung cakes has been shown to release many thousands of organic components into gas and aerosol phases, some of which are unique tracers of dung combustion such as cholestanol and coprostanol. [18] Dung cakes are generally a higher emission fuel, with the combustion of cow dung cake samples collected from the Delhi area of India releasing around four times more volatile organic compounds than fuel wood samples. [19] The volatile organic compounds released from cow dung cake combustion have been shown to be significantly more reactive with the hydroxyl radical, with the gases released from the combustion of cow dung cake samples collected from Delhi in India around 120 times more reactive with the hydroxyl radical than the emissions from liquefied petroleum gas. The volatile organic compounds from cow dung cake combustion have also been shown to result in 3-4 times more secondary organic aerosol production than fuel wood and release many more toxic polycyclic aromatic hydrocarbons. [20]
Coprophagia or coprophagy is the consumption of feces. The word is derived from the Ancient Greek κόπρος kópros "feces" and φαγεῖν phageîn "to eat". Coprophagy refers to many kinds of feces-eating, including eating feces of other species (heterospecifics), of other individuals (allocoprophagy), or one's own (autocoprophagy) – those once deposited or taken directly from the anus.
Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires, but may also be used for pest control (fumigation), communication, defensive and offensive capabilities in the military, cooking, or smoking. It is used in rituals where incense, sage, or resin is burned to produce a smell for spiritual or magical purposes. It can also be a flavoring agent and preservative.
Biogas is a gaseous renewable energy source produced from raw materials such as agricultural waste, manure, municipal waste, plant material, sewage, green waste, wastewater, and food waste. Biogas is produced by anaerobic digestion with anaerobic organisms or methanogens inside an anaerobic digester, biodigester or a bioreactor. The gas composition is primarily methane and carbon dioxide and may have small amounts of hydrogen sulfide, moisture and siloxanes. The gases methane and hydrogen can be combusted or oxidized with oxygen. This energy release allows biogas to be used as a fuel; it can be used in fuel cells and for heating purpose, such as in cooking. It can also be used in a gas engine to convert the energy in the gas into electricity and heat.
Biofuel is a fuel that is produced over a short time span from biomass, rather than by the very slow natural processes involved in the formation of fossil fuels, such as oil. Biofuel can be produced from plants or from agricultural, domestic or industrial biowaste. Biofuels are mostly used for transportation, but can also be used for heating and electricity. Biofuels are regarded as a renewable energy source. However, the use of biofuel has been controversial because of the several disadvantages associated with the use of it. These include for example : the "food vs fuel" debate, biofuel production methods being sustainable or not, leading to deforestation and loss of biodiversity or not.
Solid fuel refers to various forms of solid material that can be burnt to release energy, providing heat and light through the process of combustion. Solid fuels can be contrasted with liquid fuels and gaseous fuels. Common examples of solid fuels include wood, charcoal, peat, coal, hexamine fuel tablets, dry dung, wood pellets, corn, wheat, rice, rye, and other grains. Solid fuels are extensively used in rocketry as solid propellants. Solid fuels have been used throughout human history to create fire and solid fuel is still in widespread use throughout the world in the present day.
Dimethyl ether (DME; also known as methoxymethane) is the organic compound with the formula CH3OCH3, (sometimes ambiguously simplified to C2H6O as it is an isomer of ethanol). The simplest ether, it is a colorless gas that is a useful precursor to other organic compounds and an aerosol propellant that is currently being demonstrated for use in a variety of fuel applications.
Wood fuel is a fuel such as firewood, charcoal, chips, sheets, pellets, and sawdust. The particular form used depends upon factors such as source, quantity, quality and application. In many areas, wood is the most easily available form of fuel, requiring no tools in the case of picking up dead wood, or few tools, although as in any industry, specialized tools, such as skidders and hydraulic wood splitters, have been developed to mechanize production. Sawmill waste and construction industry by-products also include various forms of lumber tailings.
Volatile organic compounds (VOCs) are organic compounds that have a high vapor pressure at room temperature. High vapor pressure correlates with a low boiling point, which relates to the number of the sample's molecules in the surrounding air, a trait known as volatility.
Cow dung, also known as cow pats, cow pies or cow manure, is the waste product (faeces) of bovine animal species. These species include domestic cattle ("cows"), bison ("buffalo"), yak, and water buffalo. Cow dung is the undigested residue of plant matter which has passed through the animal's gut. The resultant faecal matter is rich in minerals. Color ranges from greenish to blackish, often darkening soon after exposure to air.
Non-methane volatile organic compounds (NMVOCs) are a set of organic compounds that are typically photochemically reactive in the atmosphere—marked by the exclusion of methane. NMVOCs include a large variety of chemically different compounds, such as benzene, ethanol, formaldehyde, cyclohexane, 1,1,1-trichloroethane and acetone. Essentially, NMVOCs are identical to volatile organic compounds (VOCs), but with methane excluded. Methane is excluded in air-pollution contexts because it is not toxic. It is however a very potent greenhouse gas, with low reactivity and thus a long lifetime in the atmosphere. An important subset of NMVOCs are the non-methane hydrocarbons (NMHCs).
In atmospheric chemistry, NOx is shorthand for nitric oxide and nitrogen dioxide, the nitrogen oxides that are most relevant for air pollution. These gases contribute to the formation of smog and acid rain, as well as affecting tropospheric ozone.
Biodegradable waste includes any organic matter in waste which can be broken down into carbon dioxide, water, methane, compost, humus, and simple organic molecules by micro-organisms and other living things by composting, aerobic digestion, anaerobic digestion or similar processes. It mainly includes kitchen waste, ash, soil, dung and other plant matter. In waste management, it also includes some inorganic materials which can be decomposed by bacteria. Such materials include gypsum and its products such as plasterboard and other simple sulfates which can be decomposed by sulfate reducing bacteria to yield hydrogen sulfide in anaerobic land-fill conditions.
Biomass briquettes are a biofuel substitute made of biodegradable green waste with lower emissions of greenhouses gases and carbon dioxide then traditional fuel sources. This fuel source is used as an alternative for harmful biofuels. Briquettes are used for heating, cooking fuel, and electricity generation usually in developing countries that do not have access to more modern fuel sources. Biomass briquettes have become popular in developed countries due to the accessibility, and eco-friendly impact. The briquettes can be used in the developed countries for producing electricity from steam power by heating water in boilers.
Feces are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relatively small amount of metabolic waste products such as bacterially altered bilirubin, and dead epithelial cells from the lining of the gut.
Manure is organic matter that is used as organic fertilizer in agriculture. Most manure consists of animal feces; other sources include compost and green manure. Manures contribute to the fertility of soil by adding organic matter and nutrients, such as nitrogen, that are utilised by bacteria, fungi and other organisms in the soil. Higher organisms then feed on the fungi and bacteria in a chain of life that comprises the soil food web.
Environmental problems in Delhi, India, are a threat to the well-being of the city's and area's inhabitants as well as the flora and fauna. Delhi, the ninth-most populated metropolis in the world (second largest if the entire NCR includes especially Faridabad and Gurugram– Haryana, is one of the most heavily polluted cities in India, having for instance one of the country's highest volumes of particulate matter pollution. The air quality index of Delhi is generally Good, Satisfactory and Moderate levels between March and September, and then it drastically deteriorates to Poor, Severe, or Hazardous levels in five months between October and February, due to various factors including stubble burning, burning of effigies during Vijayadashami, bursting of firecrackers burning during Diwali and cold weather. In May 2014 the World Health Organization announced New Delhi as the most polluted city in the world.
Air pollution in India is a serious environmental issue. Of the 30 most polluted cities in the world, 21 were in India in 2019. As per a study based on 2016 data, at least 140 million people in India breathe air that is 10 times or more over the WHO safe limit and 13 of the world's 20 cities with the highest annual levels of air pollution are in India. 51% of the pollution is caused by industrial pollution, 27% by vehicles, 17% by crop burning and 5% by other sources. Air pollution contributes to the premature deaths of 2 million Indians every year. Emissions come from vehicles and industry, whereas in rural areas, much of the pollution stems from biomass burning for cooking and keeping warm. In autumn and spring months, large scale crop residue burning in agriculture fields – a cheaper alternative to mechanical tilling – is a major source of smoke, smog and particulate pollution. India has a low per capita emissions of greenhouse gases but the country as a whole is the third largest greenhouse gas producer after China and the United States. A 2013 study on non-smokers has found that Indians have 30% weaker lung function than Europeans.
Omni processor is a term coined in 2012 by staff of the Water, Sanitation, Hygiene Program of the Bill & Melinda Gates Foundation to describe a range of physical, biological or chemical treatments to remove pathogens from human-generated fecal sludge, while simultaneously creating commercially valuable byproducts. An omni processor mitigates unsafe methods in developing countries of capturing and treating human waste, which annually result in the spread of disease and the deaths of more than 1.5 million children.
The Shit Museum is a museum in the province of Piacenza, in the north of Italy, and is reported to be the world's first museum dedicated to feces. The museum opened on 5 May 2015, having been founded by agricultural businessman Gianantonio Locatelli and three associates.
The air quality in Delhi, the capital territory of India, according to a WHO survey of 1,650 world cities, and a survey of 7,000 world cities by the US-based Health Effects Institute in August 2022, is the worst of any major city in the world. It also affects the districts around Delhi. Air pollution in India is estimated to kill about 2 million people every year; it is the fifth largest killer in India. India has the world's highest death rate from chronic respiratory diseases and asthma, according to the WHO. In Delhi, poor quality air irreversibly damages the lungs of 2.2 million or 50 percent of all children.
