Description
Compost screening is a key link in compost production. It aims to improve the quality of compost through particle size classification, remove undecomposed impurities, and improve the uniformity and market value of the product. Among many screening equipment, drum screening machine has become the preferred equipment in the composting industry due to its stable structure, strong adaptability and low energy consumption. The following analyzes the application of drum screen in compost screening from the aspects of working principle, technical advantages, application scenarios and precautions.
Working principle of Trommel Screen machine
The drum screening machine realizes material screening through mechanical rotation and gravity. Its core structure and process are as follows:
1. Equipment composition
Screen drum: cylindrical or polygonal screen, usually installed at an angle of 3°~5°, and the screen hole diameter is configured according to demand (such as 4~30mm).
Drive device: The motor drives the screen drum to rotate at a low speed of 5~20 RPM through a reducer.
Screen cleaning mechanism: built-in bouncing ball, comb brush or vibration device to prevent the screen hole from being blocked.
Screening process
Feeding: The compost material enters the rotating screen drum through belts, funnels, etc.
Grading: When the screen drum rotates, the material rolls under the action of centrifugal force and gravity, small particles fall through the screen, and large particles are discharged along the inclined surface of the screen drum.
Multi-stage screening: The multi-layer screen can classify coarse residue (return material), finished particles and fine powder to meet different fertilizer efficiency requirements.
Technical advantages of Trommel screen in compost screening
Compared with other equipment such as vibrating screen, drum screen performs outstandingly in compost screening:
1. Strong adaptability
It can handle high humidity (water content ≤30%) and sticky materials (such as livestock and poultry manure, sludge compost).
The screening particle size range is wide (0.1~50mm), especially suitable for gentle screening of large particles to reduce the risk of crushing.
2. High efficiency and low consumption
The processing capacity can reach 5~50 tons/hour, and the energy consumption is only 1/3~1/2 of the vibrating screen.
Optimized parameters (such as feed rate 39.6 tons/hour, speed 12.4 RPM, inclination 5.6°) can achieve 96% screening efficiency.
3. Environmental protection and easy maintenance
The sealed cover design effectively suppresses dust emission and reduces environmental pollution.
The modular screen supports quick replacement and low maintenance cost.
4. Operation stability
Slow-speed rotation reduces noise (≤75 decibels), stable operation, and low failure rate.
Application scenarios of trommel screen
1. Post-composting of compost
Fine grading of mature compost to separate undecomposed impurities such as fibers and stones.
2. Organic fertilizer production line
Matched with compost turner, crusher and granulator, it realizes the integrated process of "crushing-fermentation-screening-granulation".
3. Compound fertilizer production
Control the uniformity of compound fertilizer particles and improve the commodity quality.
Operation precautions of trommel screen
1. Material pretreatment
High-viscosity materials need to be pre-dried or anti-sticking agents added to avoid clogging of the screen holes.
2. Parameter adjustment
Dynamically adjust the screen drum inclination, speed and screen aperture according to the characteristics of the material.
3. Maintenance and safety
Regularly check the wear of the screen and clean up the residue in time.
Trommel screening machine has become the core equipment for compost screening due to its high efficiency, low consumption and strong adaptability. By optimizing parameters and scientific maintenance, the quality of compost and production efficiency can be significantly improved.
