Use cow dung as fuel
The reason why cow dung can be used as fuel is that cows eat variety of foods, such as grass, leaves, grains, wheat stalks, etc. and chews foods thoroughly. Their cow dung is therefore consist of many combustible fibers. Besides, one adult cow can shit thirteen times one day on the average, so there is ample cow dung to harvest in any barn. As dry cow dung has a moisture content of less than 30 percent, so it is more commonly used as fuel compared with moist dung. People usually knead the cow dung into melon-size balls and stick them on the wall to dry under the sun. Cow manure can be dried in 3-4 days then collected and stored to consumed as fuel for cooking or heating.
It is very common to see the phenomenon of adopting cow manure as fuel source in some places. Cow manure are stored in various ways. During winter and monsoon seasons when the sun is weak, these stored cow manure can provide people with fuel.
Why people use cow dung as fuel
Compared with other fuels , cow dung is cheaper than propane, most natural gas, and electricity. Besides, it is also very efficient. In places where wood is very scarce cow dung can be used as alternative and be used to reduce wood consumption pressure. Further more, cow manure requires short time to collect and can be readily available. Cow dung contains a reasonable amount of energy to be used as sustainable and renewable fuel source. It can also reduce disposal cost of odor and other nuisances connected with large scale farm breeding.
Disadvantages of using cow dung as fuel directly
A disadvantage of using this kind of fuel directly is increased air pollution. Even though cow dung contains about 50% methane and 30% carbon dioxide, burning it directly is a different matter and the energy that can be extracted is less. In fact, it is more difficult to efficiently burning cow dung than wood. When burning directly, cow dung will produces numbers of pollutants.
Burning cow dung directly would cause illness especially burning indoors with its limited ventilation. Consequently, the individual costs that used to treat the illness and wage cost caused by it are feared to be very high.
Before burning cow dung, people has to make the dung cake in some rural places, so it would creates social burden and cause extra work for some rural women.
As the huge output of cow dung, it needs large storage space to store the the raw material, meanwhile storage and sun-cure would also cause secondary pollution to environment.
Feasibility of cow dung fuel pellets
As directly using cow dung as fuel has many disadvantages mentioned above, cow dung fuel pellets seems to be a better choice. after pelleting, volume of cow dung fuel pellets becomes three times smaller than original, however burning time prolongs three to four times. During burning condition, there is no obvious dust or ash to be discharged, the density of discharged ash is much lower which can meet environmental protection standard.
Features of cow dung fuel pellets
1.Wide application. Cow dung fuel pellets can replace coal to be used to supply heat or as fuel. It is especially suitables for densely inhabited district.
2.It has no season limitation and can be used all the year round.
3.Making cow dung fuel pellets can reach conversion and appreciation of waste material.
4.Environmental friendly. As one green energy, sulphur content, ash content and nitrogen content of cow dung fuel pellets is much lower than coal, fossil oil, etc.
5.Low cost and high additional value. With locally abundant cow dung and cow dung pellets production line, you can make cow dung fuel pellets.
6.Big density and convenient to store. Cow dung fuel pellets has small volume and high density which makes it convenient to convert, store, transport and use.
How to make cow dung fuel pellets
Modern cow dung fuel pelletization draw lessons from the former cow dung “cakes” which are made by manually spreading cow manure on walls and drying them under solar energy. After drying, these dried flat cow dung circular pieces can be stored for the rainy and winter seasons and supply energy for cooking and heating needs. With our cow dung fuel pellets machine, you can make cow dung fuel pellets automatically.
1.Cow dung drying: as cow manure contains high moisture content, so the first step of making cow dung fuel pellets would be drying, which is the different from making other wood pellets. Drying cow dung can reduce moisture content and avoid wet manure blocking on the hammer mill.
2.Cow dung crushing: cow dung become loose after drying and can be processed by hammer mill. With hammer mill, cow dung can be crushed into powder.
3.Cow dung pelleting: after crushing, cow dung powder can be fed into cow dung pellet machine, which will press cow dung powder into pellets. This is how cow dung fuel pellets are made.
4.Cow dung fuel pellets cooling: cow dung fuel pellets has high temperature after pelleting, so it has to be cooled before using. After cooling, cow dung fuel pellets can be used to provide energy.
Except from cow dung, with our cow dung fuel pellets other animal manure such as chicken manure, horse manure and sheep manure can also be used to make livestock manure pellets.