In modern industry, the efficiency of vertical grinding systems directly impacts production costs and energy consumption. Here are several effective strategies to reduce power consumption, minimize system resistance, and optimize daily operations.
1. Reduce Main Motor Current
Use mechanical lifting for material handling to lower power consumption more effectively than air lifting. This method reduces the internal circulation load of the バーチカルミル, enhances grinding efficiency, and decreases equipment resistance. Most vertical mills today have external circulation elevators. However, you need to find the optimal balance between external circulation and system output through ongoing exploration during production.
Theoretically, a lower material layer will yield a significantly lower motor current than a higher layer. Therefore, controlling the material layer thickness is crucial. Adjust this thickness using the dam ring. By optimizing the dam ring height, you can achieve a more appropriate thickness for the material layer within the mill. A reduced layer thickness increases the effective force within a unit volume of material, lowers the hydraulic cylinder’s working pressure, and reduces the pressure difference in the mill, leading to lower main motor current.
When selecting equipment and designing processes, consider the appropriate ratio of external circulation and the suitable air velocity of the nozzle ring. Ensure that the capacity of the external circulation elevator matches the system requirements. Additionally, controlling the air volume is essential to prevent excessive fine powders during discharge.
2. Lower System Resistance
The energy consumed by the circulating fan is closely linked to wind pressure, airflow, and fan efficiency. When system resistance is high, fan efficiency decreases, leading to increased current draw. Therefore, reducing system resistance is essential for enhancing fan efficiency and lowering current consumption.
Identify the primary sources of resistance by installing pressure detection devices at key locations: the hot air inlet, classifier outlet, cyclone outlet, and nozzle ring outlet. Comparing pressure differentials at these locations will help pinpoint the main sources of resistance.
3. Address System Air Leaks
Air leaks in the vertical mill system primarily occur in the mill and the dust collector. Ensure that the leak rate remains below 8%. Key leak sources include lock air devices at the mill inlet, roller seals, connection flanges, and expansion joints. In dust collectors, significant leaks often occur at the casing cover and connection flanges.
Air leaks increase current consumption by the fan, escalate energy costs, and potentially impact the mill’s output. Therefore, timely management of air leaks is vital for improving system efficiency.
4. Daily Operational Insights
Control the particle size of incoming material, typically within 3% to 5% of the roller diameter. After wear occurs on the roller sleeves and grinding table liners, adjust the gap between the roller and the grinding table. Regularly check the accumulator pressure, maintaining it within 60% to 70% of the roller's working pressure.
Higher grinding pressure is not always beneficial. If the output reaches a critical value, further increases in motor current will worsen energy consumption and jeopardize safe operation. Therefore, determine the optimal pressure based on actual production conditions. Additionally, maintain the outlet gas temperature around 85°C to stabilize grinding and classification efficiency.
5. Central Control Operation Considerations
Grinding Pressure: Aim for a grinding pressure that does not exceed a certain critical value. Further increases can elevate the main motor current and energy consumption. Develop a curve that correlates pressure with output to optimize this aspect.
Outlet Gas Temperature: Keep the outlet gas temperature stable at around 85°C. Deviations can significantly impact grinding and classification efficiency.
Valve Settings: Open all valves, including the inlet air valve, circulation air valve, fan outlet valve, and bypass air valve, to minimize system resistance. To check if the bypass valve should remain open, close it and observe the inlet negative pressure. If it increases, re-open the bypass valve.
Negative Pressure Control: Maintain the negative pressure at the tail end of the dust collector within -500Pa. This pressure affects the volume of supplementary air entering the mill and reduces the current of the exhaust fan. If the negative pressure does not decrease, monitor the site and instruct the central control to gradually lower the tail discharge, addressing any areas where dust escapes.
Control Startup and Shutdown Times: Ensure that the time from starting the first auxiliary equipment to feeding the mill does not exceed 4 minutes. During shutdowns, if no maintenance is required, there is no need to empty the material from the mill.
By implementing these strategies, companies can significantly enhance the efficiency of their vertical grinding systems while lowering energy consumption and optimizing production processes. If you have any questions or need assistance in improving the efficiency of your vertical grinding system, please feel free to お問い合わせ. We are here to provide you with professional solutions!