Is the electric heating cable for the sulfur storage tank to use a high temperature self-limiting electric heating cable or a series electric heating cable?
Sulfur is a light yellow crystal at room temperature, with a melting point of 112-119 °C. Liquid sulfur has a unique viscosity-temperature property, has a low viscosity of 10-14 cp at 130-155 ° C., and the best fluidity; when the temperature is above 165 ° C., the viscosity directly increases, reaching more than 800 cp; when the temperature is above 190 ° C., the viscosity becomes smaller again. Therefore, in order to achieve the best state of infusion sulfur, its temperature must be maintained in the range of 130-155 °C.
Sulphuric acid has high corrosion activity and is harmful to the human body. Therefore, during production or transportation, it must be carried out through anti-corrosion pipelines. Since sulfuric acid is a liquid medium, it is prone to freeze in winter, as are water pipes. At the same time, if measures are not taken to protect against freezing and preserve heat, Sulphuric acid condenses easily, which affects production and transportation. This is taken into account by users when winter comes, so it is recommended to use electric heating cables for freezing treatment and heat preservation.
The electric heating system is mainly composed of two parts: the control unit and the electric heating cable. The control unit uses temperature control units, and each circuit is equipped with a temperature measurement point to track, measure and control the process temperature of the pipeline. At all times. Based on the specified temperature value, when the system temperature is lower than the set temperature, the circuit is automatically connected to increase the temperature of the pipeline process; when the system temperature is higher than the set temperature, the temperature control system automatically turns off. Power source and limit temperature: a set temperature is reached.
For freezing protection and heat preservation of sulfuric acid storage tanks, the choice of electric heating cables should be based on the volume or temperature requirements of the storage tanks. Generally, there are differences in the choice of electric heating cables for large storage tanks and small storage tanks Large storage tanks, Such as If the tank has a height of 20 meters and a diameter of 18 meters, it is generally recommended to use constant power electric heating cables On the contrary, for storage tanks with a diameter of 8-10 meters and a height of about 10 meters, self-regulating heating cables are more suitable.
To protect against freezing and heat preservation of sulfuric acid storage tanks, the choice of electric heating cables should be anti-corrosion. Due to the strong corrosion of sulfuric acid, the use of conventional heating cables cannot meet the requirements of heat preservation and corrosion protection. Therefore, the use of anti-corrosion electric heating cables can provide a certain degree of thermal insulation effect and service life, For this users must understand.
Electric heating cable is a heating method that uses insulation resistance or resistance heating wire to create a temperature after power supply. It can automatically adjust the output temperature and reasonably maintain the process temperature requirements to keep warm, raise the temperature and protect the heating equipment from freezing. The insulation and antifreeze effect of the container is very good.
Transport of heavy oil through the pipeline over long distances and long-term retention in the pipeline will result in a drop in temperature due to heat dissipation and increased viscosity, which will cause the pipeline to be blocked by freezing or condensation-related accidents. Electric heating is widely used as effective insulation of pipelines and anti-freeze protection.
According to the statistics of the Hydrometeorological Center, the average daily minimum temperature at the location of the CNPC tank farm is 5 ° C, and the average daily maximum temperature is 14 ° C. Since the freezing point of the PX is about 15 °C, the supply pipeline needs heat preservation and heating. The oil depot has been in operation for many years without a stable source of steam, therefore, this project is considering the use of electric heating technology.
Long-distance crude oil pipelines with a high paraffin content with freezing temperatures above 50 °C. According to the requirements of the production plan of the plant, the volume of oil transportation through the pipeline is 150 thousand rubles. Tons per year, maximum-200 thousand. Tons per year.. According to the thermodynamic analysis of the pipeline, the initial supply temperature of the pipeline is 80 ° C (TN), and the temperature of the end entering the tank is 60 ° C (Tu). Since the transportation temperature needs to be adjusted according to the time of year, it sometimes needs to be transported by heat.
In petrochemical engineering, trunk infusion pipelines are the lifeblood of the factories. The temperature in the northern region is too low in winter and the pipeline needs to be insulated to compensate for the heat loss due to the low temperature in winter to ensure the normal operation of the pipeline.
The toughness of the asphalt is greatly affected by the temperature. When the temperature decreases, the toughness of the asphalt increases, and the drop in resistance of the asphalt during pipeline transportation increases; when the temperature falls below the freezing point, the asphalt solidifies, causing the pipeline to clog and the conveyor belt to come to trouble. Therefore, electric heating and heat preservation during the transportation of asphalt are very important.
To solve many problems in the "three high levels" crude oil extraction process, the thermal energy generated by the electric heating is used to heat the crude oil in the oil pipe throughout the process to improve the fluidity of the crude oil. Effectively solve various technical problems encountered in the operation of high-condensation, high-viscosity and high-paraffin crude oil, and achieve the goal of improving the productivity and efficiency of oil wells.