As its working temperature is usually above 2000℃, the energy consumption is high, so optimizing the energy consumption not only reduces the production cost, but also reduces the carbon emission, which is in line with the requirement of sustainable development. The following discusses the energy consumption optimization strategy of high temperature graphitization furnace from the aspects of equipment design, process optimization, thermal management and automation control.

1. Optimization of equipment design

(1) Improvement of furnace structure

The design of furnace structure directly affects the efficiency of heat utilization. The traditional graphitizing furnace body usually adopts a single-layer structure, with large heat loss. By using multi-layer insulation materials (such as ceramic fiber, graphite felt, etc.) to build a composite furnace body, it can effectively reduce heat loss and improve thermal efficiency. In addition, the sealing of the furnace body is also key, good sealing design can reduce heat leakage and reduce energy consumption.

(2) Optimization of heating elements

Heating element is the core component of graphite furnace, and its performance directly affects the energy consumption. Although the traditional graphite heating element is high temperature resistant, it has high resistivity and high energy consumption. The use of new low-resistivity graphite materials or silicon carbide (SiC) heating elements can improve heating efficiency and reduce energy consumption. In addition, optimizing the layout of the heating element to make its heat distribution more uniform can also reduce the phenomenon of local overheating or inadequate heating, thus improving the overall energy efficiency.

(3) Control of furnace atmosphere

In the graphitizing process, the atmosphere inside the furnace has an important influence on energy consumption. By accurately controlling the flow and pressure of protective gases (such as nitrogen and argon) in the furnace, unnecessary heat loss can be reduced. At the same time, optimizing the gas circulation system so that it is evenly distributed in the furnace can also improve the efficiency of heat utilization.

2. Optimization of process parameters

(1) Optimization of heating curve

In the graphitizing process, the design of the heating curve has an important influence on the energy consumption. Too fast heating rate may lead to local overheating and increase energy consumption; while too slow heating rate will prolong the production cycle and also increase energy consumption. Through experiments and simulations, to find the best temperature rise curve, can ensure product quality under the premise of assuring the maximum reduction of energy consumption.

(2) Optimization of holding time

Holding time is another key parameter in the graphitizing process. Too long holding time will lead to unnecessary energy consumption, while too short holding time may affect the quality of the product. By optimizing the holding time, it is possible to reduce energy consumption while ensuring product quality.

(3) Optimization of the cooling process

The cooling process is also an important source of energy consumption. The traditional natural cooling method is inefficient, time-consuming and consumes a lot of energy. By introducing a forced cooling system (e.g. water cooling or air cooling), the cooling speed can be accelerated and the production cycle can be shortened, thus reducing energy consumption. In addition, optimizing the design of the cooling system so that it works in conjunction with the heating system can also improve overall energy efficiency.

3. Optimisation of heat management systems

(1) Waste heat recovery

Graphitizing furnace will produce a large amount of waste heat during the working process, if it is directly discharged, it will not only waste energy, but also increase the burden on the environment. By introducing a waste heat recovery system, this waste heat can be used to preheat raw materials, heat protective gases or other production processes, thus improving the efficiency of energy utilization.

(2) Heat radiation shielding

High-temperature graphitizing furnace will produce a large amount of heat radiation when working, if these radiant heat can not be effectively used, it will lead to an increase in energy consumption. By installing heat radiation shielding materials (such as high reflectivity metal coating) on the inner wall of the furnace, the loss of heat radiation can be reduced and the efficiency of heat utilization can be improved.

4. Optimization of automated control systems

(1) Intelligent temperature control system

The traditional temperature control system usually adopts simple PID control, which is difficult to adapt to the complex graphitizing process. Through the introduction of intelligent temperature control system (such as fuzzy control, neural network control, etc.), the temperature in the furnace can be monitored and adjusted in real time, so that it is always kept in the assortment of the best working condition, thus reducing energy consumption.

(2) Data acquisition and analysis

Through the installation of sensors and data acquisition systems, the temperature, pressure, gas flow and other parameters in the furnace can be monitored in real time, and the use of big data analysis technology to find out the links with high energy consumption and put forward targeted optimization measures. In addition, the data acquisition system can be used to predict equipment failure and reduce the increase in energy consumption due to equipment failure.

(3) Integration of automated production lines

Integrating the graphitizing furnace and other production equipment into the automated production line can reduce the errors and energy consumption caused by manual operation. Through the automated control system, the precise start and stop of equipment and automatic adjustment of process parameters can be realized, thus reducing energy consumption.

5. Innovations in materials and processes

(1) Application of new graphitized materials

With the development of material science, new graphitized materials (such as nanocarbon materials, graphene, etc.) are gradually applied in graphitizing furnaces. These materials have higher thermal conductivity and lower electrical resistivity, which can improve heating efficiency and reduce energy consumption.

(2) Development of new graphitizing process

The traditional graphitizing process usually requires a long time of high temperature treatment and high energy consumption. Through the development of new graphitization processes (such as microwave graphitization, plasma graphitization, etc.), graphitization can be achieved at lower temperatures, thereby significantly reducing energy consumption.

6. Maintenance and management

(1) Regular maintenance

During the use of the graphitizing furnace, heating elements, heat insulation materials and other components will gradually deteriorate, leading to an increase in energy consumption. By regularly maintaining and replacing these parts, you can keep the equipment running efficiently and reduce energy consumption.

(2) Energy consumption monitoring and management

Establishing an energy consumption monitoring system to monitor the energy consumption of the equipment in real time and formulating energy consumption management strategies based on the monitoring results can effectively reduce energy consumption. In addition, by training operators and raising their awareness of energy saving, unnecessary energy consumption can also be reduced.