Many energy saving solutions in cement production
(Baonghean.vn) - In the 2021-2025 period, Nghe An sets a goal of saving 5-7% of total energy consumption. Saving solutions are being implemented by many businesses in the production process, especially in the cement sector.
Solution from residual heat system
The waste gas thermal power generation system is a new advanced European technology solution applied in many industrial sectors. This technology is currently also applied and installed by The Vissai Cement Group in sync with the construction process of Do Luong Cement Plant and has been operating stably since the beginning of 2017.
The waste gas thermal power generation system operates based on the principle of collecting heat from the exhaust gas and residual gas of the clinker production line to get steam to run the turbine generator and generate electricity to the factory's power grid to serve the production process, contributing to reducing product costs and protecting the environment. The exhaust gas and residual gas after passing through the waste gas power generation system will be clean of dust and cooled before being discharged into the environment.
This is the best and most modern environmental protection solution in current cement production technology. According to statistics, each year this system produces over 100 million kWh, providing up to 39% of the total electricity consumption of Do Luong Cement Factory.
Along with the residual gas thermal power generation system, Do Luong Cement Factory has a very modern electrostatic dust filter system, achieving dust filtration efficiency of up to 98.8%, so the amount of dust released into the environment is almost zero. The amount of dust recovered from the residual gas thermal power generation system and electrostatic dust filter is returned to the production process, helping the factory save production costs.
Mr. Pham Xuan Khanh - Deputy Production Director, Song Lam Cement Joint Stock Company said: The residual heat system is installed and operated to recover the waste heat of the kiln system to generate electricity to serve the factory. The residual heat power generation system is installed to recover heat at 2 locations, hot air discharged when cooling Clinker (AQC kiln) and hot air from the heat exchange tower (SP kiln) on both lines.
Optimize equipment operations
To save energy, the company alternately stops equipment during peak hours to reduce electricity costs and production costs per clinker product. This helps reduce production costs due to the difference in electricity prices between peak and off-peak hours compared to normal hours, while reducing the electricity load during peak hours for the national grid. Although this method does not require investment costs, it has saved about 14.5 billion VND/year - the cost of the difference in electricity purchase prices between peak hours and normal hours.
The company also controls the operation of lighting equipment, replacing low-efficiency bulbs with higher-efficiency bulbs. When installing new or replacing broken lights, use LED lights. Regulate the lighting time frame for lighting areas in the factory.
Along with that, we need to strengthen the control of air conditioning operations. Power stations and administrative areas regulate the air conditioning temperature setting from 26 degrees Celsius to 28 degrees Celsius. Seal all air-conditioned rooms, take advantage of natural wind. Only use air conditioning after 8:00 a.m. and turn it off 15 minutes before leaving for areas working during office hours. Turn off air conditioning when not in use. Regularly maintain air conditioning, replace inefficient equipment.
In addition, the enterprise also operates the compressed air system; Turns off compressed air in locations that are not really needed, uses compressed air to cool equipment reasonably; at the same time, installs equipment such as: Installing frequency converters for the chain system to collect static dust from excess air; Installing frequency converters for 4 fans for excess air and exhaust air; Installing frequency converters for 2 coal grinding fans... These methods help to save a lot of energy, reducing up to 35-45% compared to the initial power consumption of the equipment before installing the frequency converter.
Implementing the plan for energy use and efficiency, Song Lam Cement Joint Stock Company has deployed measures, thereby bringing economic efficiency to the company and saving energy for society.
According to Deputy Production Director Pham Xuan Khanh: With the measures implemented in 2022 and by the end of April 2023, the annual electricity consumption has been reduced by more than 12,000,000 kWh, helping to save an additional ~ 7.5% of the factory's electricity consumption in the year, equivalent to 18 billion VND/year; along with the measure of stopping equipment during peak hours, the factory will save 15.5 billion VND/year.
