How to Dry Pig Manure?
This article will use swine manure as an example and will explain how to dry pig manure from the following perspectives in order to allude to the organic fertilizer drying process.
What Is The Moisture Content of Animal Manure?
Livestock manure is a kind of great raw material for organic fertilizer production since it is rich in organic matter, nitrogen, phosphorous, potassium, and medium trace elements. However, it frequently has a high water content, which is a major problem in fertilizer manufacturing process. Cow dung, for example, has a moisture content of more than 50%, chicken manure of more than 60%, fresh pig manure of more than 70%, and even swine manure by water submerging of more than 90%.
Why to Dry Swine Manure for Organic Fertilizer Production?
The moisture level of swine manure affects its treatment and usage significantly.
- Firstly, excessive moisture content raises the volume and weight of swine dung, which influences transportation and storage costs. At the same time, pig excrement with a high water content is more prone to pollute the environment.
- Secondly, the high water content makes decomposing the organic matter in pig dung more difficult.
As a result, before utilizing swine dung to manufacture organic fertilizer, you must primarily reduce its water content.
Top 3 Methods to Remove Moisture Content of Pig Dung
Moisture requirements vary depending on the different process in the organic fertilizer production line for livestock and poultry manure disposal. How to remove and manage water content in raw materials? There are four main processes.
- 1
The initial water content of animal dung is more than 60-65%.
- 2
Before fermentation, the moisture of manure after dehydration is 40-65%.
- 3
After granulation, the water content of fertilizer granules is up to 20-40%.
- 4
Drying reduces the moisture content of finished fertilizer to less than 15%.
Take pig dung as an example!
Ⅰ. Dewatering Pre-treatment of Swine Dung
For animal manure like pig dung, its moisture is always higher than 70%. At this time, we advise you to buy our inclined dewatering machine for mechanical dehydration. That is to say, it reduces water by pressing, sedimentation, filtration, centrifugal separation, etc. This method can only remove part of free water in manure, and the bound water still remains.
For instance, a farm with 3,000 pigs installs a pig dung dewatering machine. According to calculation, a pig produces 2.5kg of dung one day, so the farm totally generates 7.5 tons of dilute pig manure a day. By the dewatering machine, this farm may get approximately 3 tons of pig manure with about 50% moisture content.
Why to Choose Our Inclined Dewatering Machine for Swine Manure Disposal?
How to Use Pig Manure Inclined Dewatering Machine?
- 1
The pump lifts the swine dung to the liquid storage box of the inclined solid-liquid separator.
- 2
Pig manure wastewater spreads uniformly onto the inclined screen surface through the overflow-weir liquid distributor.
- 3
Under the action of gravity and vibration, the filtered water flows out from the screen surface’s gap to the storage box and discharges through the drainpipe.
- 4
The vibration motor pushesthe pig dung to the spiral shaft in the screen. And after extrusion and separation, they are discharged from the bottom.
Ⅱ. Composting & Fermentation of Pig Manure
The water content of swine dung remains relatively high after mechanical dewatering, often 40-60%. Composting is a typical method of turning pig excrement into organic fertilizer by adding the appropriate amount of microbial agents for fermentation. Then, you can lower the water content after composting to 30–50%, which is more suitable for organic fertilizer granulation.
Here, it should be noted that if the moisture content of pig dung after composting is too high, you may need to dry again to meet transportation and storage requirements. Meanwhile, if it occurs environmental problems such as odors, it is necessary to do further deodorization treatment.
3 Tips for Pig Manure Moisture Removal During Composting Process
During the composting process, you can absorb and neutralize moisture by adding absorbent auxiliary materials (e.g. wood chips, straw, etc.). It is also important to turn the manure regularly during this process to increase the oxygen content and promote microbial decomposition, as well as to facilitate the evaporation and dissipation of water.
In the fermentation pot, you can apply the secondary fermentation technology. In a word, you can carry out aerobic fermentation in advance, and then do anaerobic fermentation, which can remove moisture and odors better.
The fermentation equipment produced by our company covers less space and no pollution (sealed fermentation). And you can control automatically aeration, temperature, agitation and deodorization.
Processing pig manure with composting equipment is also an effective method. You can remove moisture through this iterative process of aeration, oxygen supplementation, warming and cooling.
Our company provide 3 kinds of rail type compost turner and 2 kind of windows type compost turner for your options. These equipment can accurately regulate moisture through automatic controlling and adjustments, while minimizing the amount of manual labor and time costs.
Ⅲ. Granulation & Drying of Swine Excrement
After fermentation and maturation, the pig manure’s moisture content achieves 20–40%. In the organic fertilizer production line, after crushing and mixing process, you can make pellets after crushing and mixing process. Nevertheless, the moisture content of the semi-finished particles is still high, so most of the cases we recommend to use our rotary drum dryer for drying. After the drying and cooling process, the moisture content of the particles reaches the marketing standard, less than 10%.
3 Tips for Pig Manure Moisture Removal During Granulation Process

Single Shaft Mixer Used in the Fertilizer Blending Process in Granulation Plant
According to the local soil structure, you can mix pig dung with appropriate amounts of nitrogen, phosphorus and potassium elements. Meanwhile, you can also add other additives, such as humic acid, which can improve the fertility and adaptability of the manure.
Our horizontal mixer has many models for customer’s actual production needs.

New Type Organic Fertilizer Granulator
You can use the organic fertilizer granulators to make pellets. We have four types for disposing pig dung. Among them, the new type organic fertilizer granulator is well received by customers.
It is necessary to pay attention to the control of water during this process. Too much water may lead to uneven granulation or soft particles, while too little water may lead to hard particles or impossible to granulate at all.

Dryer for Fertilizer Production
More significantly, you can purchase the organic fertilizer dryer to further remove the moisture in the semi-finished particles to meet the standard requirements.
The drying process needs to pay attention to the control of temperature and humidity in order to avoid the impact on product quality.
In conclusion, in the organic fertilizer production process, there are three methods for the water removal.
- Firstly, you can remove high water content of pig manure by dewatering machine.
- Secondly, you can use the compost fermentation equipment to make water content meet granulation requirements.
- Finally, you must use the dryer to reduce moisture to meet the marketing standard.
Please contact us for more details!