In order to ensure that we all have clean domestic water, almost every city has a sewage treatment plant. However, the domestic sludge generated by sewage treatment plants has always been a headache for environmental protection departments, as these sludge are rich in a large amount of organic matter and pathogenic bacteria, insect eggs, weed species, and heavy metal ions, which are prone to producing foul odor, breeding mosquitoes and flies, and polluting the environment. At present, three treatment methods are mainly used, namely, landfill, reclamation and incineration. The existing treatment methods are very easy to cause secondary environmental pollution and waste a lot of Organic fertilizer resources. After microbial fermentation treatment, domestic sludge can be turned into biological Organic fertilizer material, which is suitable for trees, flowers, lawns and used as the substrate for tree container seedling raising. Good growth effects have been obtained, and the physical, chemical and biological properties of soil have been improved. Thus, the resource utilization of domestic sludge has been completely realized.
The municipal sludge Organic fertilizer production line has good automatic and continuous operation, simple process structure, less equipment, and greatly reduces investment. The automation level of the process has been greatly improved by using metal thermometers for temperature measurement, electromagnetic speed regulating motors, rotary level sensors, and electronic continuous measurement sensors.
Introduction to the production line process of urban sludge Organic fertilizer material:
1. Transfer dehydrated sludge with a moisture content of about 40% (suitable viscosity) to a disc homogenizer, and add evenly mixed materials to the rotating disc of the disc granulator through uninterrupted rotation of the disc.
2. Transport to an efficient dryer and complete the preliminary drying of the fertilizer at high temperatures after treatment with a jet induced draft fan. After drying, the moisture content is controlled at 10% to 15%.
3. It is delivered to the Organic fertilizer material screening machine. The special design of the screening machine can completely solve the problem of screen adhesion.
4. The qualified particles after screening are sent to the metering silo, and the large particles are sent to the metering silo after being crushed by the Organic fertilizer material grinder to meet the requirements.
5. Qualified raw materials such as nitrogen, phosphorus, potassium, and fillers are transported to their respective measuring silos.
6. The weighed raw materials are transported to the drum granulator, and saturated steam (or water) is introduced. The materials form a rolling bed with the friction generated during the rotation of the drum granulator. The squeezing force generated by the rolling causes the materials containing a certain liquid phase to aggregate into small particles, which become the core and adhere to the surrounding powder to form qualified particles.
7. It is delivered to the Organic fertilizer material dryer for heat exchange with the heat from the hot blast stove.
8. Transported to the hot screening for particle separation, fine particles are directly returned to the drum granulator as the core and continue to participate in particle adhesion and balling.
9. The screened semi-finished particles are sent to the Organic fertilizer cooler, and the fertilizer is cooled by natural or forced cold air.
10. Transported to the finished product screening machine, the large particles are crushed by the crusher and returned to the drum granulator to continue participating in balling.
11. The qualified products after screening are transported to the coating machine for coating treatment.
12. Transport to a fully automatic packaging scale for weighing, packaging, and warehousing.
13. Drying, cooling, and workshop dust are discharged after three stages of treatment: cyclone dust collector, labyrinth dust chamber, and wet washing.
