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63-455: At Kollsnes, the Natural gas liquids (NGL) are separated out of the gas. The dry gas is compressed and then shoved by large compressors out in the pipe systems that transport it to the customers. In 1999, it was decided that the gas from Kvitebjørn was to be landed at Kollsnes. The consistency of the gas from the field made it well suited to be reprocessed to upgraded products. The new plant that

126-473: A byproduct of natural gas extraction. It is also known as "condensate", "natural gasoline", "casing head gas", "raw gas", "white gas" and "liquid gold". Drip gas is defined in the United States Code of Federal Regulations as consisting of butane , pentane , and hexane hydrocarbons . Within set ranges of distillation , drip gas may be extracted and used to denature fuel alcohol. Drip gas

189-502: A compressor will not function unless fitted with features such as stationary vanes with variable angles (known as variable inlet guide vanes and variable stators), the ability to allow some air to escape part-way along the compressor (known as interstage bleed) and being split into more than one rotating assembly (known as twin spools, for example). Axial compressors can have high efficiencies; around 90% polytropic at their design conditions. However, they are relatively expensive, requiring

252-654: A crankshaft. They can be either stationary or portable, can be single or multi-staged, and can be driven by electric motors or internal combustion engines. Small reciprocating compressors from 5 to 30  horsepower (hp) are commonly seen in automotive applications and are typically for intermittent duty. Larger reciprocating compressors well over 1,000 hp (750 kW) are commonly found in large industrial and petroleum applications. Discharge pressures can range from low pressure to very high pressure (>18000 psi or 124 MPa). In certain applications, such as air compression, multi-stage double-acting compressors are said to be

315-444: A hermetic and semi-hermetic is that there is no route for the gas to leak out of the system. The main advantages of open compressors is that they can be driven by any motive power source, allowing the most appropriate motor to be selected for the application, or even non-electric power sources such as an internal combustion engine or steam turbine , and secondly the motor of an open compressor can be serviced without opening any part of

378-450: A hermetic or semi-hermetic system can sit unused for years, and can usually be started up again at any time without requiring maintenance or experiencing any loss of system pressure. Even well lubricated seals will leak a small amount of gas over time, particularly if the refrigeration gasses are soluble in the lubricating oil, but if the seals are well manufactured and maintained this loss is very low. The disadvantage of hermetic compressors

441-425: A large number of components, tight tolerances and high quality materials. Axial compressors are used in medium to large gas turbine engines, natural gas pumping stations, and some chemical plants. Compressors used in refrigeration systems must exhibit near-zero leakage to avoid the loss of the refrigerant if they are to function for years without service. This necessitates the use of very effective seals, or even

504-756: A mention in Terrence Malick's movie Badlands . Drip gas was sold commercially at gas stations and hardware stores in North America until the early 1950s. The white gas sold today is a similar product but is produced at refineries with the carcinogen benzene removed. In 1975, the New Mexico State Police's drip gas detail – three men in pickup trucks – began patrolling oil and gas fields, catching thieves and recovering barrels of stolen gas. The detail stopped its work in 1987. The use of drip gas in cars and trucks

567-423: A positive displacement compressor is one that operates by drawing in a discrete volume of gas from its inlet then forcing that gas to exit via the compressor's outlet. The increase in the pressure of the gas is due, at least in part, to the compressor pumping it at a mass flow rate which cannot pass through the outlet at the lower pressure and density of the inlet. Reciprocating compressors use pistons driven by

630-410: A pump is to pressurize and transport liquids. The main and important types of gas compressors are illustrated and discussed below: A positive displacement compressor is a system that compresses the air by the displacement of a mechanical linkage reducing the volume (since the reduction in volume due to a piston in thermodynamics is considered as positive displacement of the piston). Put another way,

693-1053: A rotating disk or impeller in a shaped housing to force the gas to the rim of the impeller, increasing the velocity of the gas. A diffuser (divergent duct) section converts the velocity energy to pressure energy. They are primarily used for continuous, stationary service in industries such as oil refineries , chemical and petrochemical plants and natural gas processing plants. Their application can be from 100 horsepower (75 kW) to thousands of horsepower. With multiple staging, they can achieve high output pressures greater than 1,000 psi (6.9 MPa). This type of compressor, along with screw compressors, are extensively used in large refrigeration and air conditioning systems. Magnetic bearing (magnetically levitated) and air bearing centrifugal compressors exist. Many large snowmaking operations (like ski resorts ) use this type of compressor. They are also used in internal combustion engines as superchargers and turbochargers . Centrifugal compressors are used in small gas turbine engines or as

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756-479: Is a low-density mixture of hydrocarbon liquids that are present as gaseous components in the raw natural gas produced from many natural gas fields . Some gas species within the raw natural gas will condense to a liquid state if the temperature is reduced to below the hydrocarbon dew point temperature at a set pressure. The natural gas condensate is also called condensate , or gas condensate , or sometimes natural gasoline because it contains hydrocarbons within

819-522: Is a reciprocating compressor with the piston being the rotor of a linear motor. This type of compressor can compress a wide range of gases, including refrigerant, hydrogen, and natural gas. Because of this, it finds use in a wide range of applications in many different industries and can be designed to a wide range of capacities, by varying size, number of cylinders, and cylinder unloading. However, it suffers from higher losses due to clearance volumes, resistance due to discharge and suction valves, weighs more,

882-430: Is a specific type of gas compressor. Many compressors can be staged, that is, the gas is compressed several times in steps or stages, to increase discharge pressure. Often, the second stage is physically smaller than the primary stage, to accommodate the already compressed gas without reducing its pressure. Each stage further compresses the gas and increases its pressure and also temperature (if inter cooling between stages

945-400: Is also used as a cleaner and solvent as well as a lantern and stove fuel. Some early internal combustion engines —such as the first types made by Karl Benz , and early Wright brothers aircraft engines—used natural gasoline , which could be either drip gas or a similar range of hydrocarbons distilled from crude oil. Natural gasoline has an octane rating of about 30 to 50, sufficient for

1008-424: Is dangerous for crew due to the danger of explosions, oxygen displacement and the threat of asphyxiating and anaesthetizing, which can occur within a few human breaths. Because condensate is typically liquid in ambient conditions and also has very low viscosity, condensate is often used to dilute highly viscous heavier oils that cannot otherwise be efficiently transported via pipelines . In particular, condensate

1071-423: Is difficult to maintain due to having a large number of moving parts, and it has inherent vibration. An ionic liquid piston compressor , ionic compressor or ionic liquid piston pump is a hydrogen compressor based on an ionic liquid piston instead of a metal piston as in a piston-metal diaphragm compressor . Rotary screw compressors use two meshed rotating positive-displacement helical screws to force

1134-422: Is frequently mixed with bitumen from oil sands to create dilbit . In 2013, the increased use of condensate as diluent significantly increased its price in certain regions. Drip gas , so named because it can be drawn off the bottom of small chambers (called drips ) sometimes installed in pipelines from gas wells, is another name for natural-gas condensate, a naturally occurring form of gasoline obtained as

1197-457: Is higher than the output pressure of the compressor. This can cause gases to flow back and forth between the compressor and whatever is connected to its discharge line, causing oscillations. Diagonal or mixed-flow compressors are similar to centrifugal compressors, but have a radial and axial velocity component at the exit from the rotor. The diffuser is often used to turn diagonal flow to an axial rather than radial direction. Comparative to

1260-406: Is higher, require highly precise CNC machining, the impeller needs to rotate at high speeds making small compressors impractical, and surging becomes more likely. Surging is gas flow reversal, meaning that the gas goes from the discharge to the suction side, which can cause serious damage, specially in the compressor bearings and its drive shaft. It is caused by a pressure on the discharge side that

1323-432: Is less efficient than other compressor types due to losses from the clearance volume. A scroll compressor , also known as scroll pump and scroll vacuum pump , uses two interleaved spiral-like vanes to pump or compress fluids such as liquids and gases . The vane geometry may be involute , archimedean spiral , or hybrid curves. They operate more smoothly, quietly, and reliably than other types of compressors in

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1386-436: Is not used). Compressors are similar to pumps : both increase the pressure on a fluid (such as a gas) and both can transport the fluid through a pipe . The main distinction is that the focus of a compressor is to change the density or volume of the fluid, which is mostly only achievable on gases. Gases are compressible, while liquids are relatively incompressible, so compressors are rarely used for liquids. The main action of

1449-451: Is now illegal in many states. It is also harmful to modern engines due to its low octane rating, much higher combustion temperature than that of gasoline, and lack of additives. It has a distinctive smell when used as a fuel, which allowed police to sometimes catch people using drip gas illegally. Gas compressor A compressor is a mechanical device that increases the pressure of a gas by reducing its volume . An air compressor

1512-469: Is that the motor drive cannot be repaired or maintained, and the entire compressor must be replaced if a motor fails. A further disadvantage is that burnt-out windings can contaminate the whole systems, thereby requiring the system to be entirely pumped down and the gas replaced (This can also happen in semi hermetic compressors where the motor operates in the refrigerant). Typically, hermetic compressors are used in low-cost factory-assembled consumer goods where

1575-486: Is the most important or one of the most important factors to consider when designing a refrigeration or air conditioning system. This type of compressor was used as the supercharger on Volkswagen G60 and G40 engines in the early 1990s. When compared with reciprocating and rolling piston compressors, scroll compressors are more reliable since they have fewer components and have a simpler structure, are more efficient since they have no clearance volume nor valves, and possess

1638-446: The advantages both of surging less and not vibrating so much. But, when compared with screw and centrifugal compressors, scroll compressors have lower efficiencies and smaller capacities. A diaphragm compressor (also known as a membrane compressor ) is a variant of the conventional reciprocating compressor. The compression of gas occurs by the movement of a flexible membrane, instead of an intake element. The back-and-forth movement of

1701-441: The air drier, and the selection of air drier is always 1.5 times volumetric delivery of the compressor. Designs with a single screw or three screws instead of two exist. Screw compressors have fewer moving components, larger capacity, less vibration and surging, can operate at variable speeds, and typically have higher efficiency. Small sizes or low rotor speeds are not practical due to inherent leaks caused by clearance between

1764-415: The clearance volume between the piston and the compressor casing, it's 40% to 50% smaller and lighter for a given capacity (which can impact material and shipping costs when used in a product), causes less vibration, has fewer components and is more reliable than a reciprocating compressor. But its structure does not allow capacities beyond 5 refrigeration tons, is less reliable than other compressor types, and

1827-407: The compression cavities or screws and compressor housing. They depend on fine machining tolerances to avoid high leakage losses and are prone to damage if operated incorrectly or poorly serviced. Rotary vane compressors consist of a rotor with a number of blades inserted in radial slots in the rotor. The rotor is mounted offset in a larger housing that is either circular or a more complex shape. As

1890-509: The conventional centrifugal compressor (of the same stage pressure ratio), the value of the speed of the mixed flow compressor is 1.5 times larger. Axial compressors are dynamic rotating compressors that use arrays of fan-like airfoils to progressively compress a fluid. They are used where high flow rates or a compact design are required. The arrays of airfoils are set in rows, usually as pairs: one rotating and one stationary. The rotating airfoils, also known as blades or rotors , accelerate

1953-408: The cost of repair and labor is high compared to the value of the device, and it would be more economical to just purchase a new device or compressor. Semi-hermetic compressors are used in mid-sized to large refrigeration and air conditioning systems, where it is cheaper to repair and/or refurbish the compressor compared to the price of a new one. A hermetic compressor is simpler and cheaper to build than

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2016-506: The elimination of all seals and openings to form a hermetic system. These compressors are often described as being either hermetic , open , or semi-hermetic , to describe how the compressor is enclosed and how the motor drive is situated in relation to the gas or vapor being compressed. Some compressors outside of refrigeration service may also be hermetically sealed to some extent, typically when handling toxic, polluting, or expensive gasses, with most non-refrigeration applications being in

2079-520: The final compression stage of medium-sized gas turbines. Centrifugal compressors are the largest available compressors, offer higher efficiencies under partial loads, may be oil-free when using air or magnetic bearings which increases the heat transfer coefficient in evaporators and condensers, weigh up to 90% less and occupy 50% less space than reciprocating compressors, are reliable and cost less to maintain since less components are exposed to wear, and only generate minimal vibration. But, their initial cost

2142-409: The fluid. The stationary airfoils, also known as stators or vanes, decelerate and redirect the flow direction of the fluid, preparing it for the rotor blades of the next stage. Axial compressors are almost always multi-staged, with the cross-sectional area of the gas passage diminishing along the compressor to maintain an optimum axial Mach number . Beyond about 5 stages or a 4:1 design pressure ratio

2205-422: The fuel. Most were also equipped with thermosiphon cooling systems that used no water pumps. Natural convection allowed the water to flow up and out of the engine block and into the top of the radiator, where it cooled and dropped and fell to continue the cycle. Woody Guthrie 's autobiographical novel Seeds of Man begins with Woody and his uncle Jeff tapping a natural gas pipeline for drip gas. The gas also has

2268-671: The gas into a smaller space. These are usually used for continuous operation in commercial and industrial applications and may be either stationary or portable. Their application can be from 3 horsepower (2.2 kW) to over 1,200 horsepower (890 kW) and from low pressure to moderately high pressure (>1,200 psi or 8.3 MPa). The classifications of rotary screw compressors vary based on stages, cooling methods, and drive types among others. Rotary screw compressors are commercially produced in Oil Flooded, Water Flooded and Dry type. The efficiency of rotary compressors depends on

2331-856: The gasoline boiling range, and is also referred to by the shortened name condy by many workers on gas installations. Raw natural gas used to create condensate may come from any type of gas well such as: There are many condensate sources, and each has its own unique gas condensate composition. In general, gas condensate has a specific gravity ranging from 0.5 to 0.8, and is composed of hydrocarbons such as propane , butane , pentane , and hexane . Natural gas compounds with more than two carbon atoms exist as liquids at ambient temperatures and pressures. Propane , butane , and isobutane are liquid at normal temperatures only under pressure. Additionally, condensate may contain: There are hundreds of different equipment configurations to separate natural gas condensate from raw natural gas. The schematic flow diagram to

2394-419: The heavy fuel would flow to the carburetor. Shutters or curtains were typically used to restrict airflow to the radiator, keeping the engine sufficiently hot for efficient operation. Coolant temperatures in the 200 degree F range were normal. John Deere two-cylinder all-fuel tractors worked well on heavy fuel, as their long piston strokes, slow engine speeds and low compression ratios allowed for effective use of

2457-411: The heavy fuel. They were equipped with a small gasoline tank and a large fuel tank, both of which fed into a common valve supplying the fuel to the carburetor. The engine would be started on gasoline and the tractor would then be worked until the engine was sufficiently warm to change over. At that point, the fuel valve would be turned to switch the fuel supply from the gasoline tank to the fuel tank and

2520-493: The high and low pressure separators may need to be processed to remove hydrogen sulfide ( H 2 S ) before the water can be disposed of underground or reused in some fashion. Some of the raw natural gas may be re-injected into the producing formation to help maintain the reservoir pressure, or for storage pending later installation of a pipeline. Natural gas condensate is generally more flammable and explosive than normal crude oil. Operating in areas where condensate has escaped

2583-561: The low pressure separator is sent to a "booster" compressor that raises the gas pressure and sends it through a cooler, and then to the main gas compressor. At the raw natural gas processing plant, the gas will be dehydrated and acid gases and other impurities will be removed from the gas. Then, the ethane ( C 2 ), propane ( C 3 ), butanes ( C 4 ), and pentanes ( C 5 )—plus higher molecular weight hydrocarbons referred to as C 5+ —will also be removed and recovered as byproducts. The water removed from both

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2646-469: The low-compression engines of the early 20th century. By 1930, improved engines and higher compression ratios required higher-octane, refined gasolines to produce power without knocking or detonation. Beginning in the Great Depression , drip gas was used as a replacement for commercial gasoline by people in oil-producing areas. "In the days of simple engines in automobiles and farm tractors it

2709-677: The lower volume range. Often, one of the scrolls is fixed, while the other orbits eccentrically without rotating, thereby trapping and pumping or compressing pockets of fluid between the scrolls. Due to minimum clearance volume between the fixed scroll and the orbiting scroll, these compressors have a very high volumetric efficiency . These compressors are extensively used in air conditioning and refrigeration because they are lighter, smaller and have fewer moving parts than reciprocating compressors and they are also more reliable. They are more expensive though, so peltier coolers or rotary and reciprocating compressors may be used in applications where cost

2772-427: The membrane is driven by a rod and a crankshaft mechanism. Only the membrane and the compressor box come in contact with the gas being compressed. The degree of flexing and the material constituting the diaphragm affects the maintenance life of the equipment. Generally stiff metal diaphragms may only displace a few cubic centimeters of volume because the metal cannot endure large degrees of flexing without cracking, but

2835-549: The most efficient compressors available, and are typically larger, and more costly than comparable rotary units. Another type of reciprocating compressor, usually employed in automotive cabin air conditioning systems, is the swash plate or wobble plate compressor, which uses pistons moved by a swash plate mounted on a shaft (see axial piston pump ). Household, home workshop, and smaller job site compressors are typically reciprocating compressors 1.5 hp (1.1 kW) or less with an attached receiver tank. A linear compressor

2898-413: The necessary volumetric efficiency to achieve pressures up to about 13 bar (1,300 kPa; 190 psi) in a single stage. A rotary vane compressor is well suited to electric motor drive and is significantly quieter in operation than the equivalent piston compressor. Rotary vane compressors can have mechanical efficiencies of about 90%. The Rolling piston in a rolling piston style compressor plays

2961-420: The operating pressure of and the distance to the raw natural gas processing plant and may require a multi-stage compressor. The gas condensate from the high pressure separator flows through a throttling control valve to a low pressure separator. The reduction in pressure across the control valve causes the condensate to undergo a partial vaporization referred to as flash vaporization . The raw natural gas from

3024-544: The part of a partition between the vane and the rotor. Rolling piston forces gas against a stationary vane. 2 of these compressors can be mounted on the same shaft to increase capacity and reduce vibration and noise. A design without a spring is known as a swing compressor. In refrigeration and air conditioning, this type of compressor is also known as a rotary compressor, with rotary screw compressors being also known simply as screw compressors. It offers higher efficiency than reciprocating compressors due to less losses from

3087-432: The petrochemical industry. In hermetic and most semi-hermetic compressors, the compressor and motor driving the compressor are integrated, and operate within the pressurized gas envelope of the system. The motor is designed to operate in, and be cooled by, the refrigerant gas being compressed. Open compressors have an external motor driving a shaft that passes through the body of the compressor and rely on rotary seals around

3150-600: The plants at Mongstad , where the NGL from Kollsnes is fractioned into propane , butane , and naphtha . The gas from Kollsnes is transported through the four pipe systems Statpipe , Zeepipe , Europipe I , and Franpipe to continental Europe and supplies Austria , Belgium , France , Germany , the Netherlands , Spain , and the Czech Republic with gas. The pipes are owned by Gassled , operated by Gassco while

3213-427: The refrigerant system. An open pressurized system such as an automobile air conditioner can be more susceptible to leak its operating gases. Open systems rely on lubricant in the system to splash on pump components and seals. If it is not operated frequently enough, the lubricant on the seals slowly evaporates, and then the seals begin to leak until the system is no longer functional and must be recharged. By comparison,

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3276-504: The right depicts a three-stage diaphragm compressor used to compress hydrogen gas to 6,000 psi (41 MPa) for use in a prototype compressed hydrogen and compressed natural gas (CNG) fueling station built in downtown Phoenix, Arizona by the Arizona Public Service company (an electric utilities company). Reciprocating compressors were used to compress the natural gas . The reciprocating natural gas compressor

3339-409: The right depicts just one of the possible configurations. The raw natural gas feedstock from a gas well or a group of wells is cooled to lower the gas temperature to below its hydrocarbon dew point at the feedstock pressure. This condenses a large part of the gas condensate hydrocarbons. The feedstock mixture of gas, liquid condensate and water is then routed to a high pressure separator vessel where

3402-691: The rotor turns, blades slide in and out of the slots keeping contact with the outer wall of the housing. Thus, a series of increasing and decreasing volumes is created by the rotating blades. Rotary vane compressors are, with piston compressors one of the oldest of compressor technologies. With suitable port connections, the devices may be either a compressor or a vacuum pump. They can be either stationary or portable, can be single or multi-staged, and can be driven by electric motors or internal combustion engines. Dry vane machines are used at relatively low pressures (e.g., 2 bar or 200 kPa or 29 psi) for bulk material movement while oil-injected machines have

3465-427: The shaft to retain the internal pressure. The difference between the hermetic and semi-hermetic, is that the hermetic uses a one-piece welded steel casing that cannot be opened for repair; if the hermetic fails it is simply replaced with an entire new unit. A semi-hermetic uses a large cast metal shell with gasketed covers with screws that can be opened to replace motor and compressor components. The primary advantage of

3528-447: The stiffness of a metal diaphragm allows it to pump at high pressures. Rubber or silicone diaphragms are capable of enduring deep pumping strokes of very high flexion, but their low strength limits their use to low-pressure applications, and they need to be replaced as plastic embrittlement occurs. Diaphragm compressors are used for hydrogen and compressed natural gas ( CNG ) as well as in a number of other applications. The photograph on

3591-441: The technical responsibility is handled by Equinor. In 2009, the electric power consumption of the plant was 2,000 gigawatt-hours (7,200  TJ ) per year. This had increased from 1,000 gigawatt-hours (3,600 TJ) per year in 1996. 60°32′55″N 4°50′14″E  /  60.5486°N 4.8371°E  / 60.5486; 4.8371 Natural gas liquids Natural-gas condensate , also called natural gas liquids ,

3654-425: The tractors were referred to as "all-fuel". The most important factor in burning heavy fuels in a spark-ignition engine is proper fuel vaporization. Tractors designed to run on those fuels usually used a "hot" intake air manifold that allowed exhaust heat to warm the manifold and carburetor to aid vaporization. Given the poor vaporization at low temperatures, all-fuel tractors were started on gasoline, then switched to

3717-404: The water and the raw natural gas are separated and removed. If a pressure boost is required, the raw natural gas from the high pressure separator is sent to the main gas compressor , which raises the pressure of the gases to whatever pressure is required for the pipeline transportation of the gas to the raw natural gas processing plant. The main gas compressor discharge pressure will depend upon

3780-526: The water. The weight of falling water compresses the air in the top of the chamber. A submerged outlet from the chamber allows water to flow to the surface at a lower height than the intake. An outlet in the roof of the chamber supplies the compressed air to the surface. A facility on this principle was built on the Montreal River at Ragged Shutes near Cobalt, Ontario in 1910 and supplied 5,000 horsepower to nearby mines. Centrifugal compressors use

3843-522: Was built cost 3 billion  kr , with operations starting on 1 October 2004. Starting in October 2005, the gas from Visund is also landed at Kollsnes. With a capacity of 25,000,000 cubic metres (6.6 × 10 US gal) gas per day and large flexibility, the new NGL plant can process gas from new fields that would be built. Though the Vestprosess gas pipeline, the plant at Kollsnes is linked to

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3906-464: Was developed by Sertco . The prototype alternative fueling station was built in compliance with all of the prevailing safety, environmental and building codes in Phoenix to demonstrate that such fueling stations could be built in urban areas. Also known as a trompe . A mixture of air and water generated through turbulence is allowed to fall into a subterranean chamber where the air separates from

3969-614: Was not uncommon for anyone having access to a condensate well to fill his tank with 'drip,'" according to the Oklahoma Historical Society. Sometimes it worked fine. "At other times it might cause thundering backfires and clouds of foul-smelling smoke." Certain manufacturers such as John Deere made farm tractors specifically designed to run on heavy, low-octane fuels which were commonly called " distillate " or "tractor fuel". Other names were tractor vaporising oil (United Kingdom) and "power kerosene" (Australia). Often

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