合成润滑油在制程及碳氢气体压缩机中的应用

Presentation on theme: "合成润滑油在制程及碳氢气体压缩机中的应用"— Presentation transcript:

1 合成润滑油在制程及碳氢气体压缩机中的应用
John C. Tolfa CPI 公司 CPI Engineering Services, Inc. has the most complete line of rotary screw compressor fluid offered in the world. As the major supplier to all U.S. rotary screw compressor original equipment manufactures, CPI is recognized as a world leader in compressor fluid technology. Now in its 24th year of existence, CPI is aggressively pursuing international markets with our proven compressor fluid technology. All fluids offered by CPI have been developed and formulated to original equipment manufacturer (OEM) operating requirements, and can be used in any brand of compressor.. Viscosity's and lubricant additives have been designed for compatibility with materials of construction. More important, they are superior to all other brands of synthetic and mineral oil based fluids. Several examples will be presented in order to support this claim.

2 压缩机的应用 空气 冷冻 天然气（碳氢气体） 化学的工艺流程 工业气体 (惰性气体)
Synthetic lubricants are being called on to meet the requirements of all types of positive displacement compressor applications. Air, refrigeration, hydrocarbon, chemical processing and inert (industrial) gas compressors all have been running for years on conventional mineral oil based lubricants. However, these lubricants often fail when high or low temperature extremes, extreme dilution by either the gas or condensables, or chemically hostile gases are encountered. Synthetic lubricants offer many advantages over conventional mineral oil based lubricants. Some of these advantages are unique to a given lubricant type, such as excellent chemical inertness, high viscosity index, low pour pint, excellent hydrolytic stability and demulsifibility, good natural lubricity, excellent thermal stability, resistance to hydrocarbon dilution, low volatility and both elastomer and metal compatibility. Since no one lubricant provides all of theses desired properties, knowledge of the physical properties and unique qualities of the various synthetic base stocks is important for proper lubricant selection.

3 旋转叶片式压缩机的内部构造 Before we discuss our fluids, an introduction to the lubrication of each type of compressor will be presented. Rotary vane compressors are once-through lubrication. The lubricant provides a thin film between the vanes and compressor housing. This thin film not only lubricates, but also seals against recompression. An ISO 100 or 150 viscosity grade is typically recommended.

4 往复式压缩机的内部构造 Differences in construction of reciprocating compressors affect the oil selection. Double acting and some single acting machines use crosshead guides with connecting pins to join the crosshead to connecting rods. Single-acting one and two stage compressors are designed with connecting rods connected to the pistons, with wrist pins or piston pins (1). Lubrication of reciprocating compressors is required in the crankcase and the upper end cylinder parts, piston rings, rod pacings and valves. Crankcase parts include crankpin, crosshead (or wristpin) bearing, crossheads and crosshead guides. Small compressors may be splash lubricated from the crankcase. Larger compressors may have lube pump supplying the upper end with crankcase oil or a separate lube pump and reservoir supplying fresh oil to cylinders and rod packings. The latter is usually specified on very large systems when makeup rates are high or if a different type of lubricant is desired. Depending on the operating conditions and the application, ISO 68 to 680 viscosity grade lubricant may be required.

5 螺杆式压缩机的内部构造 It is important the function of the compressor fluid be understood to have a full appreciation for the advantages these premium fluid offer over conventional mineral oils. Not just any fluid can lubricate this kind of compressor. The functions of a rotary screw compressor fluid are to: -Lubricate the shaft seals, bearing and rotating screws -Remove the heat of compression -Provide a seal between screws and housing so gas can be compressed without blow-by -Remove contaminants from the system, ie: wear materials -protect against corrosion.

6 轴承 - 10-20 cSt 转子- 主要接触点 - 5 cSt 密封面 - 4-15 cSt 润滑 （最适当的油膜厚度） 粘度 －油膜
The viscosity requirements of a rotary screw compressor are listed. We must provide no less than cSt. (depending on the compressor manufacturer) at the bearings to assure proper lubrication. No less than 5 cSt. is allowed at the rotor tips in order to assure proper lubrication between the intermeshing screw, but just as important, to assure a proper seal is created between the screws and the compressor housing. If this requirement is not met, blow by can cause efficiency losses. Typically 4-15 cSt. are required at the that seal faces.

7 螺杆式压缩机流程 图 气体入口 气体出口 润滑剂清除剂流线 压缩机 空气 / 润滑油 分离器 润滑油和气体 输入轴承 注入 输出轴承 轴封
Because the fluid is recirculated in a closed system, from the compressor to the separator, pumped to a cooler, filtered and back to the compressor, it is extremely important that the lubricant maintain its lubricant properties and integrity throughout its useful life. Breakdown of the lubricant or its capabilities will lead to compressor problems. Therefore, it is important to use the best fluid, designed to meet these harsh demands. Another important consideration is the solubility between the gas and the lubricant. When gases are compressed, they can dissolve in the lubricant if the two are soluble. As we will see later, this reduces the lubricant's viscosity. Too much dilution in this closed loop system can reduce the viscosity beyond usefulness. CPI provides application engineering to assure the proper lubricant is selected for each specialty application. We work with the compressor OEMs and packagers before the system is installed to assure the system is operated properly with the correct fluid. Our expert advise is often relied upon to determine if a rotary screw compressor is suitable for an application or not. In many instances, a CPI synthetic fluid is the only reason a rotary screw can be used when harsh environments or soluble gases at high pressures are encountered. 输出轴承 轴封 热通道阀 润滑油冷却器 润滑油泵 过滤器

8 合成油的种类 烷基苯类 卤化烃类 有机酯类 磷酸酯类 聚醚类 聚烯烃 硅油 硅酸盐酯 其他
There are several classes or families of synthetic lubricants. Each which offer specific benefits. This slide outlines many of the synthetic lubricants used in the market today

9 合成油的优异特征 抗氧化性 高温稳定性 良好的溶解特性和低结胶性 水解稳定性 低挥发性 化学惰性
Each synthetic fluid type has its own inherent chemical and physical properties. When designing a synthetic lubricant or selecting one for an application, it is necessary to know these properties, since there is no-one fluid that will meet the needs of all application. Some attractive features are listed. CPI synthetic fluids possess excellent thermal and oxidative resistance, which is important for long life. Good solvency for degradation by products and low varnish tendency, means the system will be kept clean and operate more efficiently. Excellent hydrolytic stability means the fluids are not degraded when in the presence of water. The is extremely important in compressor applications since water is usually present, and under high pressure conditions, can condense. Low volatility keep the fluid from carrying over, particularly at the high temperatures seen in high pressure applications. Finally, good chemical inertness is necessary to resist degradation when a hostile chemical is encountered in process gas and hydrocarbon gas applications containing H2S.

10 典型的环烷烃矿物油 CH2 - CH2 R - C CH - CH2 - CH2 - CH = CH - CH3 N H
The differences between lubricant basestock chemical structures, whether mineral oil or synthetic is what give them their unique properties. Mineral oils are blends of Naphthenic and parraffinic basestocks. The source of crude oil determine who much of each is present and the consistency between lubricants often varies. The naphthenic basestock is susceptible to thermal and oxidative degradation due to the high structure seen on the left, and also the double bonds (sited of hydrogen unsaturation) located throughout the molecule. These are weaknesses within this molecule allow them to break down in a compressor when high temperature (>80 degrees C) and hostile chemicals are encountered.

11 典型的石蜡基矿物油 CH2 CH2 CH CH2 CH3 CH3 - CH - CH2 - CH - C = CH2 - CH3 CH2
The structure is free of rings and isomer branched. Double bonds, are still present and as with the napthenic basestocks are susceptible to degradation due to heat , oxygen and other hostile chemicals. CH2 CH3

12 聚烯烃 的结构 CH3 CH3 (CH2)7 (CH2)7 CH2 CH2 CH (CH2)7 CH3
PAOs, and semi-synthetics display excellent resistance to chemical attack. A few applications such as pure oxygen compressors are limited to the exotic, completely fluorinated, or chlorinated oils. Applications where acids and other highly reactive chemicals are encountered can be handled if the proper bas fluids are chosen. Semi-synthetic basestocks are relatively new to the lubricant industry (1970’s). They are manufactured from crude oil as are solvent refined basestocks. The solvent refining step is replaced with hydrocracking step. This step subjects crude oil fractions to hydrogen at thigh temperature, 300 C (700 F) and pressure 20, 785 kPa (3000 psi). Sulfur, nitrogen and oxygen combing compounds are entirely decomposed. Polycycloparafins, are broken up and aromatic compounds are converted into saturated cycloparafins two vacuum distillation steps at elevated temperatures remove volatile materials and other contaminates. Dewaxing and second stage hydrotreating remove the balance of impurities Semi-synthetic chemical composition is a blend of stable isoparaffinic and cycloparaffinic lubricant hydrocarbons giving many of the same advantages as PAOs (8). Blends with other synthetics further enhance these properties. (CH2)7 CH3

13 ISO 220 油品的粘度 – 温度曲线图 20,000 10,000 300 200 40 20 10 3 PAG 粘度, cSt PAO
Another key feature of synthetics is their good viscosity index characteristics. CP-4601, as with all CPI synthetics, lose less viscosity with increasing temperature than mineral oils. This offer more viscosity at the higher temperatures seen at bearings, providing better fluid films for lubrication and more viscosity at the rotor tips, offering better sealing for improved efficiency. Less viscosity at lower temperatures during startup also offer energy savings. 白油 温度, °C

14 半合成加氢裂解油, PAO （聚烯烃）和环烷烃ISO 68 的油品 -- 挥发性比较图
These graphs illustrate the superior low volatility characteristics of the PAO and Semi-synthetic hydrocracked basestocks over mineral oils. Low vapor pressure due to increased thermal stability, and purity of synthetic basestocks mean less oil carries over past the oil separator. Less oil is consumed by the compressor and less oil ends up down stream to interfere with downstream equipment and operations. * °C

15 典型的工业用气体 二氧化碳 氦 氢 氮 Gas purity is crucial when the gas is used in a chemical process. Catalyst poisoning is also a consideration for these gases. For these reasons, only the highest quality base fluids can be used to lubricate compressors handling the following inert process and industrial gases: .hydrogen .helium .carbon dioxide .nitrogen The low volatility of synthetic compressor lubricants results in negligible contamination of the process gas by volatile components. Process gases are usually pure and anhydrous, so lubricant additives usually are not needed. PAOs and semi-synthetic base fluids are relatively insoluble with these gases and offer better volumetric efficiency in rotary compressors. Our CP-4600 Series products are commonly used in these applications.

16 化工工艺流程中气体压缩机的应用 氯化甲烷 二氧化硫 氯化氢气体（盐酸） 其他
Synthetic lubricants have provided successful solutions to compressor problems associated with chemically hostile gases. Reactions may occur with conventional mineral oils. Many chemical plant applications prohibit the use of petroleum based lubricants due to possible contamination of catalysts. Typical gases include: .methyl chloride .sulfur dioxide .hydrochloric acid .ammonia

17 有关润滑油品质的需求 基础油 与 添加剂的相容性 对腐蚀及氧化的保护 抗气体的溶解 低挥发性 良好的 粘度指数
The lubricant requirements for Process Gas applications are listed.

18 在哪里你可以发现碳氢气体的压缩机？ 炼油厂 天然气田的集气站 天然气储存及运输设备 蒸汽及废气回收系统
填埋气体（ 垃圾发电厂）或电力发电工厂 气电共生设备 汽轮机的进气压缩机 The next section of this presentation will address Natural And other Hydrogen Gas Compressor Applications. Hydrocarbon gas applications include all of the applications listed on this slide.

19 典型的碳氢气体与油 的混合关系图 70°C 60°C 300 200 100 50°C 压力, PSIA 40°C 30°C 20°C
典型的碳氢气体与油 的混合关系图 70°C 60°C 300 200 100 50°C 压力, PSIA 40°C 30°C Hydrocarbons are infinitely soluble with most lubricating fluids. The degree of solubility depends on compressor operating pressure and temperature. This figure depicts propane dilution of a 220 ISO polypropylene glycol at various temperatures and pressures. Increasing pressure at a given temperature results in more hydrocarbon gas dilution of the lubricant, while increasing the temperature at a constant pressure will result in less dilution. 20°C % 气体

20 碳氢气体与油混合 —— 典型的粘度稀释效果图
1000 500 200 100 50 40 20 10 5 4 0% 气体 10% 气体 20% 气体 30% 气体 粘度, cSt This dilution reduces the oil’s viscosity, as shown in the viscosity vs. temperature curve with hydrocarbon dilution. If dilution is severe enough, the viscosity of the fluid may be reduced to a level where it is no longer sufficient for adequate lubrication, which could lead to premature equipment failure. 温度, °C

21 润滑油的选择 压缩机的形态 气体的成分 压缩机工作条件
Viscosity is the most critical lubricant requirement that must be met in the rotary screw compressor when handling hydrocarbon gases. The flow diagram shown earlier shows the closed loop system of the lubricant. In the compressor, the gas and oil are violently mixed during the compression stage. The gas/oil mixture is then separated. The oil leaving the gas/oil separator is filtered, pumped to the compressor bearings, and reinjected into the compressor housing where the loop cycle began. The lubricant leaving the separator will be diluted with hydrocarbons. The amount of dilution depends upon the temperature and pressure present in the separator, which are at the actual discharge conditions of the compressor. The temperature may drop if there is sufficient loss through the distance piece between the separator and compressor and if the separator is open to cool ambient temperatures. Downstream equipment must be insulated to help keep temperatures of the gas as high as possible to help keep hydrocarbons in the vapor phase. Proper lubricant selection is critical for rotary screw compressor applications in order to ensure proper viscosity for successful operation. The following information must be known in order to select the proper lubricant: gas composition, compressor operating conditions, and compressor manufacturer. A knowledge of the complete gas composition including the amount present of each component is required for engineering the correct lubricant. The compressor operating conditions of concerns are discharge pressure and temperature, and lubricant temperature at the compressor bearings. Water H2S asphaltenes or other trace contaminants including possible solids must be considered. To assemble all needed information, good communication between the original compressor manufacturer, the packager who designs and assembles the system and the end user is required. Poor communication can result in misinformation and ultimately to compressor failure if viscosity requirements are not properly analyzed and met. Once all the above information has been collected, proper lubricant selection can be made. Hydrocarbon dilution is calculated based on the gas composition and operating conditions. A computer program is used by CPI Application Engineers to make these calculations to give the amount of each gas component present in the lubricant at the discharge conditions. Once the dilution has been calculated, diluted viscosity's are determined for a selected lubricant from viscosity/temperature curves with hydrocarbon dilution. The diluted viscosity must meet the compressor manufacturer’s viscosity requirements. If dilution is more than is allowable, higher temperatures above 93 C (200 F), PAOs or other synthetics are recommended because of their excellent thermal stability. These elevated temperatures may be beyond the thermal capabilities of conventional lubricants. PAOs and polyalkylene glycols are compatible with elastomers used in systems designed for use in hydrocarbon processing.

22 聚醚类的结构 R1 R2 R - O ( - C - C - O - C - C - O - )n - R3
If vapor equilibrium calculations show severe dilution which cannot be sufficiently reduced by higher operating temperatures, or if hydrocarbon condensation occurs, a polyglycol based synthetic lubricant is recommended, Polyalkylene glycol contains oxygen, and is a polar molecule, opposed to nonpolar hydrocarbons. There are different types of polyglycols available, which offer unique solubility characteristics, dependent on their physical make-up and structure. Advantages include low hydrocarbon solubility, high viscosity index, unique water solubility and clean operation. Our CP-1516 Fluids are used in propane production and refrigeration applications because of their resistance to dilution with hydrocarbons compared to a conventional mineral oil of the same viscosity. This resistance to dilution results in less loss of viscosity for a given application than would be with mineral oil of PAO. Advantages such as higher volumetric efficiency and energy saving s have been proven and are often the main criteria in their selection. Difficult applications with heavier hydrocarbons, C4 butane and above, can cause severe dilution or condensation of the gas. Fortunately, there are other types of polyglycols available that offer additional resistance to hydrocarbons. Our CP-1515 will allow 10 to 20 percent hydrocarbon solubility by weight before the fluid is saturated. Any additional liquid hydrocarbons would be present as a second phase on top of the lubricant since the copolymer has a higher density. CP-1515 is water soluble, displays an inverse solubility with water above 60 C (140 F) to 70 C (158 F) and resists viscosity loss with up to 20 percent water dissolved at lover temperature. The absorption of water helps to prevent corrosion during compressor shut down, particularly where H2S is present and specially designed additives are used to protect metal surfaces from chemical corrosion. Our CP offers complete resistance to hydrocarbon dilution. Falling ball viscosity carried out at kPa (2000psi) with a typical well head gas proved no loss in viscosity. Lubricant samples taken in high-pressure vessels from the lube/gas separator of hydrocarbon compressor systems have been tested for hydrocarbon dilution, which confirmed no dilution or loss in viscosity. CP is water-soluble. Results from four-ball wear tests have shown no loss in lubricity with seven- percent water by weight present in the lubricant. In many heavy hydrocarbon gas compressor applications, CPI polyglycols can be the sole bases for the selection of a rotary screw compressor. Proper viscosity is assured even with unexpected changes in the gas a composition or operating conditions. At high pressures, hydrocarbons can condense and collect in the separator, even though these are not soluble in the polygycols. If excessive levels exist, liquid hydrocarbons may be pulled through the lubricant system. If slugs of liquid hydrocarbons reach the compressor bearings, damage and failure will occur. The liquid hydrocarbon layer on top of the lubricant layer in the oil fill line in the separator can be removed easily by means of a valve strategically located a few inches above the oil fill line in the separator as seen when the systems is running. Simple float valves have been installed in the field to decant this layer automatically. One large vapor recovery system running on CP is recovering 12,100 liters (32300 gallons) per day of liquid hexane. The recovered value of hexane’s resulted in a six-month payback on the complete compressor system. Similar results have been obtained on butane, propane, and other hydrocarbons. Also, higher-pressure systems have been designed with special flash tanks to remove water accumulation. 在: R1和 R2 = H 或 CH3

23 合成润滑油常用的 场合: 抗化学分解 抗稀释（气体溶解在润滑油里面） 防腐蚀 在极端条件下的润滑 提高安全性
In summary, synthetics allow drain intervals to be extended many times beyond mineral oils due to their chemical inertness. Their resistance to hydrocarbon dilution allows rotary screw compressor to be used where it would be impossible with a mineral oil based fluid. Proper additive formulation allows the corrosive gas to be handled and because of their good viscosity index and low pour points, can be used over a wide temperature range. High Flash and fire points increase the safety in high pressure/temperature application.

24 做润滑油品推荐所需的讯息 填CPI 气体成分调查表 (摩尔% 或重量 %) 压缩机抽气温度 压缩机抽气压力 压缩机排气温度 压缩机排放压力
油入口的温度 (冷却油之后的温度)

25 其他特殊考虑 环境（周围）的温度范围 水的饱和度（水含量） 气体的最终用途 管道 气电共生设备 涡轮机的进气设备 等等

26 CP-1516 系列 不溶于水 抗碳氢气体的稀释 但并非完全不溶解 低蒸汽压力 添加剂 抗氧化剂 防锈剂及抗腐蚀剂 抗磨剂 消泡剂

27 CP-1515 系列 在140℉以下溶与水 在 160 ℉以上不溶与水 低的蒸汽压力 将允许 20% (重量百分比) 碳氢气体的稀释
比碳氢气体和水的比重更高 添加剂 抗氧化剂 防锈剂 抗磨剂 抗硫化氢（H2S）侵蚀剂 消泡剂

28 CP-4601 系列 极好的化学稳定性 极好的热稳定性 极好的抗水及破乳化性 极低的蒸汽压力 可溶于碳氢气体 密度比水低 低倾点 添加剂
抗氧化剂 防锈及抗腐蚀剂 消泡剂

29 CP-9001 系列 极好的化学惰性 较好的热稳定性 极好的抗水及破乳化性 极低的蒸汽压力 可溶于碳氢气体 比重比水低 添加剂 抗氧化剂
防锈及抗腐蚀剂 消泡剂

30 CP-1005 系列 极好的化学惰性 较好的热稳定性 极好的抗水及破乳化性 极低的蒸汽压力 可溶于碳氢气体 密度比水低 添加剂 抗氧化剂
抗硫化氢（H2S）腐蚀剂 消泡剂 倾点抑制剂

31 CP-1507 系列 完全不能溶于碳氢气体 完全溶与水 极好的热稳定性 极好的低蒸汽压力 添加剂 防锈剂及抗腐蚀剂 消泡剂

32 CP-1516 系列的应用 丙烷的冷冻压缩 轻的碳氢气体——在没有很严重的气体稀释或浓缩（冷凝）的情况下

33 CP-1515 系列--应用 酸性气体的压缩机 重的碳氢气体—有严重的碳氢气体稀释或浓缩（冷凝）的情况下

34 CP-4601 系列－应用 掩埋气体（垃圾发电） 较轻的碳氢气体 高温的应用 (高于 200°F) 涡轮进气的增压压缩机
低的周围或 户外温度的应用

35 CP-9001 系列－应用 掩埋气体（垃圾发电） 较轻的碳氢气体 涡轮进气的增压压缩机

36 CP-1005系列－应用 较酸的气体--压缩机 较轻的碳氢气体

37 CP-1507系列－应用 较重的碳氢气体 高压碳氢气体 低温的碳氢气体冷冻

38 在聚醚类（PAG）与 矿物油中—丙烷的溶解度图
250 200 150 100 50 100 ISO PAG 100 ISO 矿物油

39 合成润滑油常用的场合: 抗化学分解 抗稀释（气体溶解在润滑油里面） 防腐蚀 在极端条件下的润滑 提高安全性