During the petroleum refining process, wax oil, due to its high viscosity and high pour point, exhibits poor fluidity in low-temperature environments, making it difficult to meet the flowability requirements for modern fuels and lubricants. Traditional hydrogen dewaxing methods are effective but come with high costs and energy consumption. In recent years, non-hydrogen dewaxing technology has gained attention in the petroleum industry due to its advantages of being environmentally friendly and cost-effective. This article focuses on the application and technical advantages of non-hydrogen dewaxing equipment in low-temperature treatment, providing valuable insights for industry professionals.
1. What is Non-Hydrogen Dewaxing Technology?
Non-hydrogen dewaxing technology is a method of reducing the pour point and viscosity of wax oil without the use of hydrogen. This technology alters the molecular structure or dispersibility of wax oil through physical or chemical means, thereby improving its low-temperature fluidity. Compared to traditional hydrogen dewaxing methods, non-hydrogen dewaxing is more environmentally friendly and suitable for processing various types of wax oils. Its core advantage lies in the absence of high-pressure hydrogen and complex catalyst systems, which saves costs and reduces operational risks.
2. Working Principle of Non-Hydrogen Dewaxing Equipment
Non-hydrogen dewaxing equipment typically processes wax oil in the following ways to improve its low-temperature flowability:
1. Crystallization Method
The crystallization method leverages the solubility properties of high pour-point components in the wax oil, inducing crystallization by cooling. This allows the separation of these high-pour-point substances, thereby lowering the overall pour point. This method is highly effective for processing wax oil with high pour points.
2. Dewaxing Agent Addition
By adding dewaxing agents, the structure of wax molecules in the wax oil is altered, making it less likely to crystallize or changing the way it crystallizes, thus lowering the pour point. Dewaxing agents vary and can include polyolefins, esters, and others. The addition of dewaxing agents requires no complex equipment and is suitable for wax oils of varying viscosities.
3. Solvent Extraction Method
The solvent extraction method uses solvents to separate long-chain alkanes (wax) and other components from the wax oil, achieving a dewaxing effect. This method effectively removes wax molecules but requires solvent recovery and treatment.
4. Centrifugal Separation Method
Centrifugal force is used to separate high-pour-point components from the wax oil, lowering the pour point. This method is fast and environmentally friendly, making it suitable for large-scale production applications.
3. Advantages of Non-Hydrogen Dewaxing Equipment in Low-Temperature Treatment
1. Energy Efficiency and Environmental Friendliness
Non-hydrogen dewaxing equipment does not require hydrogen or high-pressure systems, greatly reducing energy consumption and production costs. Compared to traditional hydrogenation equipment, non-hydrogen dewaxing equipment is more environmentally friendly and aligns with the trend of low-carbon production.
2. Lower Maintenance Costs
Traditional hydrogenation equipment involves high-pressure operations and catalyst management, resulting in higher maintenance costs. Non-hydrogen dewaxing equipment lacks complex high-pressure systems, making maintenance simpler and operation safer.
3. Strong Adaptability
Non-hydrogen dewaxing equipment can be flexibly adjusted to process different types of wax oil and meet various low-temperature flowability requirements, making it suitable for a wide range of wax oil products and process needs.
4. Short Investment Payback Period
Compared to the high initial investment required for hydrogen dewaxing equipment, non-hydrogen dewaxing equipment has relatively low procurement and operating costs, allowing for a quick return on investment. It is suitable for small to medium-sized refineries and businesses that require rapid production adjustments.
4. Practical Applications of Non-Hydrogen Dewaxing Equipment
1. Dewaxing in Diesel Production
Diesel fuel used in winter or cold regions must exhibit good low-temperature fluidity to prevent fuel system blockages. Non-hydrogen dewaxing equipment can improve the low-temperature performance of diesel fuel through the addition of dewaxing agents or low-temperature separation, ensuring the proper operation of vehicles in cold environments.
2. Improvement of Lubricant Low-Temperature Performance
Lubricants need to maintain stable viscosity at varying temperatures. The application of non-hydrogen dewaxing equipment in lubricant production can enhance their flowability in low-temperature environments, thus extending the service life of machinery.
3. Processing of High-Viscosity Base Oils
Non-hydrogen dewaxing equipment can also be used in the dewaxing of high-viscosity base oils, reducing their low-temperature viscosity to meet the requirements of different applications.
4. Low-Temperature Treatment of Aviation Fuels
Aviation fuels require high low-temperature flowability, especially in high-altitude, low-temperature environments. Non-hydrogen dewaxing equipment improves the low-temperature performance of aviation fuel by separating waxy components or adding flowability-improving agents.
5. Maintenance Key Points for Non-Hydrogen Dewaxing Equipment
1. Regular Cleaning of Equipment Pipes
Due to the viscosity of wax oil, there is a tendency for deposits to form in the equipment pipes. Regular cleaning is necessary to prevent blockages and reduce flow rate, ensuring the efficiency of dewaxing.
2. Stabilizing Dewaxing Agent Storage and Addition Systems
When using dewaxing agents, it is important to ensure the purity of the agents and the accuracy of the addition system. Regular checks on the addition amount of the dewaxing agent should be conducted to ensure effective dewaxing.
3. Inspecting Separators and Filters
For equipment using centrifugal or solvent extraction separation, periodic checks on the separator and filter’s working condition should be performed to ensure they can effectively separate high-pour-point substances from the wax oil.
4. Low-Temperature Testing of Equipment
Regular low-temperature testing of equipment should be conducted to verify the flowability and pour point of wax oil products under low-temperature conditions, ensuring that dewaxing results meet production requirements.
6. Conclusion
Non-hydrogen dewaxing equipment is gaining popularity in low-temperature treatment applications due to its energy efficiency, ease of operation, and low maintenance costs. Compared to traditional hydrogen dewaxing methods, non-hydrogen dewaxing technology does not rely on hydrogen, making it more suitable for production needs that emphasize low cost and environmental sustainability. By choosing the appropriate non-hydrogen dewaxing technology and maintaining equipment effectively, it is possible to significantly improve product low-temperature performance while reducing production costs.
In the future, as environmental requirements and energy conservation awareness increase, the application prospects of non-hydrogen dewaxing equipment in petroleum refining and fine chemical industries will be even broader.
