Complete Guide to Energy Efficiency Ratio Calculation and Energy-saving
Optimization of Electromagnetic Dry Powder Magnetic Separator
Core formula: Energy Efficiency Ratio = (Quantity of Qualified Materials ×
Unit Sorting Power) ÷ Total Power Consumption of Equipment
This indicator directly determines the competitiveness of production costs.
This article will explain in detail the calculation method and the path to
improvement.
1. Four-step method for precise calculation of energy efficiency ratio
1. Statistics of qualified material quantity
Effective material sorted per hour (ton) = Raw material processing capacity ×
(Iron content of raw material - Iron content of finished product)
*Example: For a 12-ton/hour quartz sand feedstock with 0.18% iron content and
a finished product with 0.025% iron content, the quantity of qualified material
= 12 × (0.18% - 0.025%) = 0.0186 tons/hour*
2. Unit sorting power value
The theoretical energy consumption required per ton of qualified material,
according to industry experience, ranges from 0.8 to 1.2 kWh/ton (with a value
of 1.05 for quartz sand)
3. Actual measurement of total power consumption of equipment
- Main energy consumption: excitation system (voltage × current × power
factor) + conveyor motor (rated power × load factor)
- Auxiliary energy consumption: cooling system (air cooling/water cooling) +
control circuit (approximately 5%)
*Example: excitation power consumption 8.55 kW + transmission 1.05 kW +
cooling 0.75 kW = total power consumption 10.35 kW*
4. Final calculation
Energy efficiency ratio = (0.0186 tons/hour × 1.05 kWh/ton) ÷ 10.35 kW ≈
0.00189
II. Three major energy-saving technologies enhance energy efficiency
ratio
1. Intelligent excitation control
- Dynamic voltage regulation technology: automatically reduces current by 15%
when the iron content is below 0.1%
- Application of superconducting coils: Reduce excitation loss by 75%
(requires a supporting liquid nitrogen system)
2. Efficient structural design
- Dual-stage magnetic field configuration: 2000 Gauss rough selection zone +
5000 Gauss fine selection zone, with energy consumption reduced by 30%
- Material thickness optimization: The thickness of the quartz sand layer is
strictly controlled at 3-5 cm
3. Smart energy management
- Real-time monitoring via the Internet of Things: Automatically matching the
optimal current and conveying speed
- Peak-load shifting production strategy: Arrange the processing of high-iron
content raw materials during the low-price period of electricity
III. Benchmarking of industry energy efficiency level
- Traditional electromagnetic equipment: energy efficiency ratio of
0.0015-0.0022, power consumption per ton of sand of 1.8-2.5 kWh
- Permanent magnet electromagnetic composite machine: energy efficiency ratio
of 0.0028-0.0035, power consumption per ton of sand is 1.2-1.6 kWh
- Superconducting magnetic separator: energy efficiency ratio ≥0.0040, power
consumption per ton of sand ≤0.9 kWh
(Benchmark: Reduce the iron content in raw materials from 0.2% to 0.03%)
IV. Empirical Analysis of Transformational Economic Benefits
Reconstruction of a production line with an annual output of 100,000 tons for
a certain enterprise in Fujian:
- Before transformation: annual electricity cost of 176,000 yuan (ton
consumption of 2.2 kWh)
- Renovation measures:
Intelligent pressure regulating module (80,000 yuan) + permanent magnet
roughing zone (150,000 yuan)
- After renovation:
The power consumption per ton has been reduced to 1.5 kWh, resulting in an
annual electricity cost savings of 56,000 yuan
The revenue from increased production is 32,000 yuan, and the total annual
revenue is 88,000 yuan
- Recycling cycle: 230,000 investment ÷ 88,000 earnings ≈ 2.6 years
V. Key points of operation and maintenance management
1. Monthly inspection
- Measure the temperature rise of the excitation coil (maintenance required
if it exceeds 20℃)
- Cleaning magnetic pole adsorption iron chips (thickness > 5mm, energy
consumption increases by 15%)
2. Quarterly maintenance
- Calibrate the accuracy of the Gaussian meter (with an error of <±3%)
- Water cooling system checks water hardness (must be softened if >200
mg/L)
Warning case: A factory in Guangdong experienced an annual loss of over
200,000 yuan due to its failure to promptly remove iron chips, resulting in an
increase in electricity consumption per ton of sand from 1.8 to 2.4 kWh
conclusion
By precisely calculating the energy efficiency ratio and implementing key
technologies such as magnetic field optimization and intelligent control, it is
entirely feasible to achieve an advanced energy efficiency level of over 0.003.
It is recommended that enterprises establish equipment energy consumption
records, and control the electric control of the magnetic separation process to
within 8% of the total cost of sheet production (the industry average is
12-15%), in order to create a core advantage in green competitiveness.