Table 1 compressor performance parameters project parameter name detailed description equipment operating environment adapt to the environment oilfield operating environment ambient temperature a 3440 altitude <2800m maximum humidity 80% continuous running time continuous working clutch transmission parameter model SL250 (hydraulic pressure clutch transmission) input speed 12001800RPM input shaft power 220KW1800RPM lubrication form oil lubrication (15W-40) lubricating oil cooling form air cooling transmission mode direct connection transmission speed ratio 11:1 (input and output shaft same rotation direction) speed ratio 21.33:1 (input and output shaft same direction Supercharger unit technical parameters compressor model KNOX- WESTERNE2430 compression medium natural gas rated displacement 1600 丽 3/HH design suction pressure 3. 0MPA rated exhaust pressure 3.0MPA25MPA compression series 3 input shaft speed 900RPM1800RPM input shaft power 208. 7BHP lubrication form with oil lubrication (Lalishi 827) cooling form air-cooled transmission mode direct connection (high elastic coupling WV-FLM-840) flywheel model 2-20729-001 engine model ohmin (LXBXH) weight 16500KG control system Control mode automatic + manual control ordinary container digital mode control + mechanical control booster explosion-proof lubricating oil heater often There are three types of optional gas sources for the gas pumping of the booster in the north of the gas field: the reinjection of the gas in the well: the gas in the well is the gas source produced by the gas well as the gas source is pressurized by the supercharger. The oil sump is recirculated into the well through the annulus, and the bottom hole effusion is discharged from the oil pipe. For low-yield wells and flood-discharged production wells, the gas volume of the well is small and the water content is high, which cannot meet the requirements of the gas source. Therefore, such wells are not considered as compressed gas sources. Gas produced in the adjacent well: the gas in the adjacent well is in the block with normal production well conditions. The gas produced by the adjacent well is pressurized by the supercharger and then used as a high-pressure gas source for continuous gas lift production. It is required that the distance between the gas source well and the gas lift well should not be too long, and the supercharger equipment is required to have a good sand and water separation device. Because there is a certain amount of excitement and back pressure damage to the formation during the gas lift process, the smooth control of the gas lift process should be strengthened to reduce the impact on the formation. Counter-gas transmission in the station: The anti-gas transmission in the station is to use the natural gas after dehydration and separation in the gas collection station as a gas source, and then deliver it to the supercharger equipment for supercharging, and then perform gas lift production. Because the gas source sent by the counter-gas transmission in the station is dry gas, there is no need for the compressor equipment to separate the sand water, and at the same time, it will not cause the excitement of the gas source well, compared with the gas of the well and the gas of the adjacent well. It is more suitable as a gas source, but it needs to be modified. Positive lifting: gas is injected from the oil pipe, and the liquid in the well is returned by the oil jacket. This method has the advantages of short-time high-pressure gas reaching the shoe, short working time of high pressure, low pressure of required gas source, but also gas. The shortcomings of incomplete emptying and large loss of wellbore slippage are mentioned. Counter-lift: Injecting gas from the oil jacket annulus, the fluid in the well is discharged by the oil pipe. Compared with the positive lifting, the high pressure gas reaches the tube shoe for a long time, the high pressure operation time is long, and the required air source pressure is also high, but the hollowing degree is thorough and the oil pipe slippage loss is small. Positive and negative lifting method selection: The general gas lifting process mainly adopts the counter-lifting method. The main reason is that when the pumping pressure and the pressure of the gas in the well are the same, the gas volume is reduced by the reverse pressure, the oil pipe slippage loss is small, and the hollowing degree is completely However, due to the high pressure of the required gas source, the large amount of liquid in the gas well cannot be effectively restored by this method. To this end, before the gas lift operation, the gas lift method should be reasonably selected according to the height of the wellbore liquid column. The selection criteria for the gas lift method can be calculated based on the wellbore pressure balance relationship. Assume that the oil jacket pressure before the gas lift operation is Pt, Pc, oil, casing! The height of the inner liquid column is hi and h2 respectively (see). According to the pressure balance relationship in the wellbore, the premise of achieving the gas lift induced spray is that the gas source pressure is greater than the bottom hole flow pressure when the gas reaches the tube shoe. Assuming that the pressure of the air source is P, the conditions for the reverse stimuli are realized: (2) There is a valve gas lift, no valve gas lift process, no valve gas lift, and only one oil pipe in the well. The gas lift valve discharges a production pipe column to install a gas lift valve, and the stepwise staged pressurized gas lift. For gas wells with wellhead pressure caused by wellbore effusion, there is no self-spraying ability to discharge the effluent to resume production. It is necessary to rely on the pressurized gas to discharge the wellbore effluent and the liquid entering the formation, and the gas injection when the supercharger lifts the liquid column. The pressure is generally high, and it is easy to cause the formation to invert. In addition, when the oil pipe is inserted into a gas well with a deep depth, it is difficult to empty the wellbore at one time when the supercharger gas is lifted. The multi-stage gas lift valve is used to lift the wellbore liquid column step by step, which can effectively reduce the starting pressure of the deep well drainage. Avoid or reduce damage to the formation caused by excessive back pressure. There are valve gas lift and valveless gas lift mode options: It can be seen that there are valve gas lift and valveless gas lift compared with the following characteristics: d, installation gas lift valve generally requires lower control gas injection speed, So as not to stab the gas lift valve. e. If the well with the gas lift valve is installed, the semi-closed gas lift and the fully closed gas lift are used. Because the packer is placed in the well (positive lift) or the bottom of the tubing is blocked (reverse lift), the gas injection space is The well bottom layer is separated to prevent the gas injection pressure from being higher than the formation pressure, and the gas is injected into the production layer so that the water in the oil pipe cannot be discharged. 199 based on the above characteristics A valveless gas lift can be used for ground laminatingH tidal press machine valve gas lift schematic http:// higher gas well for gas lift liquid extraction, or gas well return after operation row. The valve gas lift method is suitable for gas lift drainage and gas drainage with large liquid accumulation and low formation pressure. (3) The structure of the pipe string is selected to open the gas lift: there is no other change in the oil pipe except the gas lift valve. Suitable for flooded wells with high formation pressure, also known as conventional gas lift. Semi-closed gas lift: The lower packer (positive lift) or the bottom of the tubing (reverse lift) separates the gas injection space from the comparison of the valve gas lift and the valveless gas lift start process. Suitable for flooded wells with low formation pressure. Fully closed gas lift: the inner and lower packers of the casing; the oil pipe shoe has a single flow valve, gas and water can enter the oil pipe, and the water in the oil pipe cannot be returned to the bottom of the well. When the water in the oil pipe is lifted out, when the internal pressure of the oil pipe is less than the formation pressure, the single flow valve is opened, and the gas water enters the oil pipe and is continuously lifted out of the wellhead. Suitable for flooded wells with lower formation pressure. Jet type gas lift: a jet pump is installed on the bottom of the oil pipe on the basis of the semi-closed gas lift device, and the injected high pressure gas is sprayed upward through the injection pipe to form a suction to the bottom of the oil well to further reduce the bottom hole flow pressure and improve The water carrying capacity of the gas. Test situation and conclusions In order to restore the production of water flooding production wells and solve the problem of gas well returning after underground operation, in 2012, the Weibei gas field carried out a total of the wells and the i4 wells. The gas is returned to the row test. Table 2 2012 supercharger gas lift test situation statistics serial number construction type construction time gas source remarks station reverse gas transmission successful return operation adjacent gas well interconnection casing damage, gas lift pressure does not rise adjacent well gas interconnection gas source sand The treatment of water is not completely caused by the reverse gas transmission in the shutdown station. The reverse gas transmission in the gas station is reversed (by the performance limit of the supercharger). The reverse gas transmission in the resumption production station is intermittent gas lift (limited by the performance of the supercharger) Test conclusion: The overall effect of the test is good, and the water-flooded well can be restored to production. The supercharger separation system has poor treatment effect on sand and water, the equipment is unstable, and it is easy to stop, and further modification is needed. Due to the performance limitations of the supercharger, continuous gas lift cannot be achieved. 1 Liu Wei (2089-3! Female a Qinghai Oilfield Natural Gas Development Company 涩3 North No. 1 gas production area gas production, telephone (1.http://
It can slow down the reaction, maintain chemical balance, reduce surface tension, prevent light, thermal decomposition or oxidative decomposition. it mainly includes lead salts, metal soaps, organic tin, organic antimony, organic rare earths, pure organic compounds. Thermal stabilizers commonly used in industry mainly include lead salts, metal soaps, organic tin, organic antimony, organic rare earths, pure organic compounds, etc.
1.1 Organotin Lead Salt Stabilizer, Compound Stabilizer,Pvc Stabilizer,Titanium Dioxide Anatase Henan Shunbang Chemical Industry CO.,Ltd , https://www.sbcpe.com
(1) Excellent transparency The biggest advantage of organotin stabilizers is that they have excellent transparency. The use of organotin stabilizers in PVC formulations can produce crystalline products. Because of this, organic tin can be used in bottles, containers, corrugated boards, various types of rigid packaging containers, hoses, profiles, films, etc.
(2) Extraordinary thermal stability In terms of thermal stability, there is no other type of thermal stabilizer that can surpass it. Therefore, it is the preferred stabilizer for rigid PVC, and some varieties have better performance in soft products. Suitable for all PVC homopolymers, such as emulsion, suspension and bulk PVC, as well as vinyl chloride copolymers, graft polymers and polymer blends.
(3) The product is non-toxic. Most organotin stabilizers are non-toxic, and the migration of organotin stabilizers in rigid PVC is minimal. Therefore, organotin stabilizers are the preferred heat stabilizers for PVC for food contact.
(4) Good compatibility. Organotin stabilizers have good compatibility with PVC, so there is generally no precipitation on the metal surface, such as lead salt stabilizers and metal soap stabilizer systems.
(5) Poor lubricity Sulfur-containing tin stabilizers have poor self-lubricity. Therefore, many commercially available sulfur-containing organotins are equipped with lubricants to prevent hot melt from adhering to processing equipment during processing.
(6) High cost Compared with other types of stabilizers, the overall performance of organotin stabilizers is closer to the ideal stabilizer. However, all organotin stabilizers, regardless of their structure, have the main disadvantage that their manufacturing cost is much higher than that of lead stabilizers or metal soap compounds. In recent years, by adopting new synthetic technology, or reducing its usage in formulas, its formula cost has been reduced. In the 1970s, foreign countries developed low-priced tin products, which reduced the tin content, which also reduced the price to a certain extent.
1.2 Lead salt
(1) l Excellent stability experiments proved that among the commonly used basic lead salts, the heat resistance of sulfite is better than that of sulfate, and the heat resistance of sulfate is better than that of phosphite. The tribasic lead sulfate, which is widely used in the PVC industry, has a higher effective lead content and shows better thermal stability than other products.
(2) Excellent insulation. Because lead salt is non-ionic and non-conductive, it is inert, which makes lead salt stabilizers widely used in wire and cable industries.
(3) Excellent weather resistance. Many salt compounds can act as white pigments and can show strong covering power, so they have strong weather resistance.
(4) Poor transparency Transparency is a problem related to weather resistance. When used in wires, cables and record materials, there is no need to care about transparency, because most of these products are white or very dark black.
(5) Inexpensive lead salt stabilizer is the lowest price among all stabilizers. Therefore, despite the continuous introduction of new stabilizers, lead salt stabilizers still dominate the stabilizer market after half a century. The composite lead salt introduced to solve the dust and dispersion problem has increased in price, but still maintains a competitive advantage with other types of stabilizers.
(6) The toxicity of the toxic lead salt stabilizer limits its application in many occasions with strict hygiene requirements. For example, many countries have revised the lead content standards in drinking water, and it is no longer possible to use lead salt in PVC water pipes.
(7) Poor dispersibility The dispersibility of salt lead is poor, but the newly launched one-package product is equipped with lubricants, which solves the dispersibility problem to a certain extent. Because of the above characteristics of lead salt stabilizers, they are especially suitable for high-temperature processing. They are widely used in various opaque hard and soft products and cable materials, such as various pipes, plates, indoor and outdoor profiles, foam plastics, artificial leather, and wires. Cables, records, welding rods, etc. The most important lead salt stabilizers are tribasic lead sulfate, dibasic lead phosphite, and dibasic lead stearate.
1.3 Organic antimony
(1) Better stability. The organic antimony stabilizer has basically the same color stability and lower melt viscosity as organotin at the same temperature. In the twin-screw extrusion process, the effect is particularly outstanding when used in combination with calcium stearate. .
(2) The price of organic antimony stabilizer is much lower than that of methyl tin or butyl tin. In addition, the amount of organic antimony used is relatively low, so the use of organic antimony can achieve a better performance/price balance.
(3) The product is non-toxic. In the United States, when a twin-screw extruder is used to manufacture PVC pipes, the PVC water supply pipe manufactured with a formula composed of antimony stabilizers, calcium stearate and other lubricants conforms to the U.S. NSF (National Sanitation Foundation) )Regulation.
(4) Poor transparency and light stability. The transparency of organic antimony compounds is not as good as organotin stabilizers, and it is also lower than the barium/fu and calcium/zinc metal soap system. It is close to lead salts and has poor light stability, so antimony is stable. The agent is mostly used for indoor products without color requirements. The antimony stabilizer itself is also required to be stored in an opaque container.
(5) Poor lubricity. Antimony stabilizers have poor lubricity. Therefore, its use must be combined with a large amount of lubricant without exception.
1.4 Metal soap
(1) The tin soap stabilizer Fu soap is the best type of metal soap. Its advantages are also reflected in the absence of initial coloring, and can produce colorless and transparent products; excellent light stability; it has the effect of preventing precipitation and adhesion. . However, because tin salt is toxic, there are strict regulations on its manufacture and use in the Labor Safety and Health Law. In recent years, the use of Fuzao has shown a downward trend.
(2) Zinc soap stabilizerThe thermal stability of zinc-based stabilizer to PVC is extremely poor. The sample with zinc soap suddenly turns black when heated, that is, the so-called "Zine burning" phenomenon occurs, but it has the following advantages: The initial coloring is excellent; the effect of preventing fouling is good; it can improve the weather resistance; many zinc soaps are recognized as non-toxic stabilizers, so they can be used in non-toxic formulations with calcium soaps.
(3) Barium soap stabilizer Barium compounds have good thermal stability and good lubricity, but the red initial coloration occurs during processing, and it is easy to cause sticking to the roller.
(4) The stability of calcium soap stabilizer is poor, but it is recognized as a non-toxic additive in the world and has excellent lubricity.
(5) Other metal soap stabilizers used in the industry include magnesium stearate, file stearate, aluminum stearate, potassium stearate, etc., among which magnesium stearate is similar to calcium stearate and can be used Materials that are in contact with food; aluminum stearate is similar to zinc stearate, and is approved by the U.S. FDA and the Japanese Vinyl Chloride Food Hygiene Association for food packaging; Stearic Acid files and potassium stearate are also non-toxic products and belong to lead salts , Tin soap and barium soap substitute.
(6) The performance requirements of the composite metal soap stabilizer processing industry for stabilizers are various, and a single metal soap often cannot meet the use requirements, so the use of composite stabilizers has become a trend. A single metal soap compound is rarely used in the PVC industry, and it is usually a compound of several metal soaps. This compound is not a simple addition of properties, but takes advantage of the synergy between the components. The composite metal soap stabilizer generally includes the stabilizer main body (i.e. metal soap), solvent (organic solvent, plasticizer, liquid non-metal stabilizer, etc.), functional additives (auxiliary stabilizer, transparency modifier, light stabilizer, Lubricants, etc.). According to the form, it is divided into solid compound and liquid compound. According to the main component, it can be divided into calcium/zinc compound stabilizer, barium/fu compound stabilizer, barium/zinc compound stabilizer, etc. Among them, the calcium/zinc composite stabilizer has a pivotal role in replacing toxic metals because it is non-toxic.
1.5 Rare earth stabilizer
(1) Excellent thermal stability The thermal stability of rare earth stabilizers is better than traditional lead salt series and barium/zinc, barium/ho/zinc stabilizers. In some applications, rare earth stabilizers can partially or completely replace organotin.
(2) Good transparency. The refractive index of rare earth stabilizers is very close to that of PVC Resin, which can replace traditional organotin and be used in the field of products with higher transparency requirements.
(3) Excellent weather resistance. Rare earth elements can absorb 230-320nm ultraviolet light. Therefore, rare earth stabilizers have anti-photoaging effects and are suitable for outdoor products such as PVC corrugated boards and window materials.
(4) Excellent electrical insulation properties. Some rare earth multifunctional stabilizers can be used to replace lead salt stabilizers in cable material formulations, and their electrical insulation properties are comparable to lead salts.
(5) Non-toxic, safe and hygienic. Rare earth elements are low-toxic elements and have no toxic hazards to the human body in their production, processing, transportation and storage. Rare earth stabilizers are non-toxic products and can be used in food packaging and medical packaging products.
(6) The processing performance is slightly worse. In the case of a large amount of rare earth stabilizer, the roll release of the material is not ideal, and there is a tendency to press out. Generally, better results can be achieved by using stearic acid or calcium stearate in combination.
In summary, rare earth stabilizers can be used for water pipes, injection pipe fittings, window frame profiles, door panels, wire ducts, foam products, artificial leather, cable materials, soft and hard transparent products, food packaging materials, etc.
1.6 Auxiliary stabilizers Auxiliary stabilizers include phosphite, epoxy soybean oil, hindered phenols, etc., which mainly rely on the synergistic effect between metal stabilizers to improve the stabilizing effect, and are generally called co-stabilizers. In addition to compounds such as mesaminocrotonic acid ester, 2-phenyl saccharin, vein derivatives, and diketone can be used in combination with metal stabilizers to improve the effect of metal stabilizers, they also have a certain stabilizing effect. Such compounds are usually called pure organic stabilizers. With the development of PVC stabilizers today, the progress of metal stabilizers is relatively slow, and the research and development of auxiliary stabilizers are unprecedentedly active, which has constituted a major trend in the field of PvC stabilizers. Auxiliary stabilizers are rarely used alone, and are often used in conjunction with primary stabilizers to improve initial coloration or improve long-term stability.