Organic fertilizer wet granulation process

The organic fertilizer wet granulation process adopts Stirring Tooth Granulator, which can produce solid spherical particles at a moisture content of 20% to 40%, which greatly saves energy and equipment, and improves efficiency.

Organic fertilizer wet granulation steps:

1. Fermentation process section

Using 20 tons of cow manure, 10 tons of chicken manure, and 20 tons of pig manure as raw materials, biological strains are added, and the fermentation temperature is controlled at 50-60°C. After the fermentation is completed, the color is dark brown, with no manure odor but compost smell. After the biogas is collected, it enters the biogas boiler and burns through the water-sealed tank and flame arrestor to provide heat for the fermentation device, granulation, drying, and other units.

2. Compound process section

①Crush
The ingredients (straw, straw, bean cake, bone meal, hoof powder, etc.) are crushed, and the inorganic fertilizer is crushed.
②Raw material compounding and mixing
Organic and inorganic ingredients are mixed according to different series of products. Blend well in a blender. Let’s say it’s 12%, about 12 tons.
③Water content control
Add straw powder or organic material with a high moisture content of grass charcoal C/N ratio, the added amount is 6 tons/day of charcoal, 6 tons/day of grass carbon, 18 tons/day of straw and straw, and the moisture content of raw materials after treatment is 60% -65%, C/N ratio 20-30. The added substance must be sufficiently broken.

3. Granulation process

① Crush
After being fermented and stored for 1 day, it is crushed, and the fermented organic material is dried, crushed, and sieved.
②Composition and mixing
In the process of making a series of special fertilizer, according to different soil conditions and different crops, add inorganic nutrients and concentrate organic matter and trace element minerals, so that the fertilizer contains a variety of nutrients needed for plant growth, such as nitrogen, phosphorus, potassium, sodium, manganese, zinc, copper and so on. According to the formula will be nitrogen, phosphorus, potassium, and good fermentation materials for computer mixing ratio, conveying to the granulator for granulation. The formula of organic and inorganic raw materials is mixed according to different series of products. Mix well in a blender. If the ratio is 12%, about 12 tons.
③Granulation
Since the production of biological fertilizers is mainly based on organic matter, there is a lot of cellulose, the forming conditions are poor, and the living bacteria that can make fertilizer are added, the production process should not be exposed to high temperature. For the production of organic biological fertilizer, the New organic fertilizer granulator is used for wet granulation. After granulation, the material is sent to the dryer through a belt conveyor for drying. The particle diameter was 3.0-4.0mm, and the granulation rate was greater than 70%.

④Drying
In the production process of biological fertilizers, the water content of the pellets after forming generally exceeds the target, and low-temperature drying is required. After the organic material is fermented, the water content is about 30% to 40%, and the water content of the pellets after granulation is generally 15%. ～20%, the fertilizer quality index requires that the water content is lower than 14%, and it needs to be dried. Therefore, the drying section is an indispensable and important process in the production of biological fertilizers, which directly affects the output, quality, and energy consumption. It is very important to select the model and specifications of the dryer reasonably and to control the process conditions.

In order to avoid the death of effective live bacteria due to high temperature during the drying process, the drying temperature of the material should not be higher than 60°C (generally 50°C). For this reason, the temperature of the hot air in contact with the material should be determined according to the moisture content of the material. The difference is generally no more than 130°C. It is better to control the temperature of the hot air in sections, which can improve the thermal efficiency and avoid the death of effective live bacteria. According to these characteristics, it is more appropriate to choose a belt dryer. This machine is suitable for low-temperature and low-moisture drying, and the temperature of hot air can be controlled in sections to ensure that the temperature of the material is not higher than the specified temperature during the entire drying process. The natural air cooling section can also be added so that the material can be cooled immediately after drying, which has a multi-purpose function. It is very suitable for drying granular biological fertilizers with good air permeability, and the material is dried smoothly and uniformly. Subject to any damage, the residence time and feeding speed can be adjusted to achieve a better drying effect. Since most of the hot air can be recycled and the thermal efficiency is high, the heat source can be steam provided by a biogas boiler.
There is a section of secondary granulation area at the front of the dryer, and the material can realize secondary granulation in this section. Then the material is lifted by the lifting plate to fully dry the material, the tail of the dryer is drawn out through the pipe through the exhaust fan, and the hottest air is drawn into the settling chamber to settle. After the tail gas passes through the settling, it passes through the washing tower to spray dust and spray water. It is pumped out by the water pump for recycling, and after the second dust reduction treatment, the exhaust gas is discharged into the atmosphere through the chimney.

⑤Cooling
The dried material is cooled by the belt conveyor and sent into the cooler. The cooling process mainly uses a fan to send natural air into the cooler through the pipe to cool the material. The air direction in the cooler is countercurrent and is drawn through the fan and pipe. The tail gas entering the settling chamber is treated the same as the drying tail gas and discharged into the atmosphere.

After cooling, the material enters the screening, and the large particle material enters the return belt together with the screened powder after crushing and is transported to the granulator for granulation, and the finished product enters the automatic packaging system for packaging.