In order to ensure that residents have clean domestic water, basically every city has a sewage treatment plant. However, the sewage sludge produced by sewage treatment plants has always been a headache for the environmental protection departments because these sludges are rich in organic matter and pathogenic bacteria, eggs, weed species and heavy metal ions, polluting the environment. At present, three treatment methods of landfill, reclamation and incineration are mainly used. The prior art treatment method is very likely to cause secondary pollution of the environment and waste a large amount of organic fertilizer resources. After many years of painstaking research by our technicians, the domestic sludge can be turned into bio-organic fertilizer after microbial fermentation treatment, thus fully realizing the resource utilization of domestic sludge.
Below we look at the sludge organic fertilizer production process
1. Adjust the moisture of raw materials:
Adding water-absorbing auxiliary materials to the sludge, such as domestic garbage and crushed crop straws, branches, leaves and sludge fertilizers with low water content after fermentation: general sludge accounts for 60%-70%, and water-absorbing auxiliary materials such as domestic garbage account for about 30% - 40% or so.
2. Add sludge starter:
Generally, it is added before the fermentation, and the fermenting bacteria are evenly mixed with the sludge by the function of turning over and stirring, and the addition amount of the composite fermenting agent is generally about 0.1% to 0.3%. It is only necessary to apply the sludge starter to the sludge.
3. turn pile fermentation:
After high-temperature fermentation, it can effectively kill pathogenic microorganisms and aphid eggs in sludge, fix heavy metals in microorganisms, or become insoluble carbonates to prevent heavy metals from entering the food chain. There are two types of tumbling fermentation methods: ground strip pile fermentation using a crawler type turning machine
; and trough type tumbling fermentation using a groove type turning machine
4. Material crushing:
Since the fermented material contains small agglomerates, it is not suitable for granulation of the finished product. At this time, the organic fertilizer pulverizer
can be used to pulverize the material.
5. material mixing:
The pulverized material is transported to the ingredient warehouse, sent to the main conveyor through automatic batching, and sent to the mixer for stirring
6. material granulation:
Small and medium-sized organic fertilizer plants generally use a disc granulator
to granulate, which can save investment costs and a high sphericity rate, which can reach more than 93%. There are three kinds of large, medium and small particles. The angle of the granulation disc must be adjusted to a certain position. The angle is determined according to the particle size. The larger the angle, the smaller the particle, the smaller the angle, the larger the particle.
7. Organic fertilizer drying and cooling process:
The granulated semi-finished organic fertilizer granules are sent to the dryer through the main conveyor for drying. The drying temperature is controlled below 70 degrees, because the water content of the feed is about 35%-40%, and the temperature is too high, the raw materials will be used. The beneficial bacteria in the killing, the retention time of the particles in the dryer is 40-45 minutes, and the rotation speed of the dryer is 4.5-5 turns, which can reach the discharge port.
The dried organic fertilizer finished granules are sent to a sieving machine through a conveyor to sort out large, medium and small granules. The larger granules are sent to the pulverizer for granulation through the return belt, and the middle and finished materials are sent to the cooler for cooling, because the particles have a certain temperature, the particles are cooled and sent, and the two sieves separate the fine powder.
8. finished packaging
The granulated finished organic fertilizer granules are sent to the organic fertilizer automatic packaging machine through the conveyor, and the packaging can be carried out.
The bio-organic fertilizer produced by applying sludge can improve soil activity, effectively repair soil compaction caused by long-term use of inorganic fertilizer and chemical fertilizer; it is beneficial to the absorption of nutrients and the balance of nutrition, and the beneficial bacteria can greatly promote the residue in the soil. The effective release of nutrients such as nitrogen, phosphorus and potassium can increase the yield and increase the yield of crops and prevent a variety of soil pests and diseases.