What classifications of the piston type compressor?
The piston compressor has various kinds of types, and also has different kinds of classification.
It is classified into vertical, horizontal type, angle type, symmetrical balance and contrast-position type according to the figuration of cylinder in the piston compressor.
It can be classified into single stage type, double stage and multistage according to the the compressed series of the piston compressor.
As for the set mode of the piston compressor, it can be classified into mobile type and stationary type.
It can be classified into unloading type and pressure switch type according to the control type of the piston compressor.
How the compressor works?
The theory of the piston compressor works: AS the piston to reciprocate in the cylinder to cyclically change the gas volume of the cylinder.
The crankshaft of the piston compressor rotate a circle, the piston reciprocate once, the cylinder successively complete air inlet, compression and discharge process.
What characteristics of the piston compressor?
The piston compressor has its unique advantages, and it also has disadvantages.
Advantages: A wide range of pressure usage; high thermal efficiency, lower unit energy-consumption; a wide range of discharge; lower requirement of material; mature technology, enriched production experience; simple device system.
Disadvantages: lower rotation, larger and heavy machine;complicate structure, difficult maintenance; interrupted discharge; larger vibration of running.
Because the air separation plant is always involved in pressure vessel issue， so the pressure vessel is also one part of air separation plant.
The first article : in order to make sure the safe operation of the pressure vessel and protect the safety of people’s lives and property and to promote the development of national economy, this code is formulated according to the relevant provisions of the Interim Regulations on safety supervision of boilers and pressure vessels.
The second article: The applicable scope of this procedure is as follows;
This procedure is applicable to pressure vessels with the following conditions
Maximum working pressure (Pw) (note 1) greater than 0.1MPA (no hydrostatic pressure, same below)
Inner diameter (non-circular section refers to its maximum size) is greater than or equal to 0.15m, and volume (V) (note 2) is greater than or equal to 0.25m3;
(The medium is a gaseous liquefied gas or the highest operating temperature is above equal to the standard boiling point liquid.
Chapters III, fourth and fifth of this code apply to the following pressure vessels.
A separate cylinder in a storage tank Boiler room with a non independent volume of a mobile compressor, less than or equal to 0.15m3.
High pressure vessel with volume less than 0.25m3
The cold box of the pressure vessel and the air separation equipment in the pressure vessel, the direct-fired absorption refrigeration unit of the cryogenic unit;
Spiral Plate Heat exchanger
Gas or air pressure water supply (foam) pressure tank for hydraulic automatic air pressure water supply (no tower Sheung Shui) device, air pressure tank in fire extinguishing device.
Pressure vessels for ion exchange or filtration in water treatment equipment, expansion tanks for hot water boilers.
All-closed combined electrical apparatus (capacitor pressure vessel) dedicated to power industry.
Tire vulcanizing machine and pressure rubber mould used in rubber industry.
This procedure is applicable to safety accessories such as safety valve, bursting piece device, emergency shut-off device, safety interlock device, pressure gauge, liquid level meter and temperature meter used in the pressure vessel.
The pressure vessel applicable in this procedure shall include, in addition to the body,
Welded groove of the first circumferential weld to which the pressure vessel is welded with an external pipe or device, the first threaded joint of the threaded connection, the first flange sealing surface of the flange connection, the first sealing surface of a special connecting piece or a pipe fitting.
Pressure vessel openings part of the bearing gland and its fastener
Welded joints of non-pressurized components connected to pressure vessel body.
3rd article This procedure does not apply to the following pressure vessel
Ultra High Pressure vessel
All kinds of gas cylinders.
Pressure vessels made of non-metallic materials.
Nuclear pressure vessels, ships and railway locomotives, ancillary pressure vessels, pressure vessels and pressure vessels working under vacuum (excluding jacket pressure vessels), and various boilers safety technical supervision procedures applicable to the fire-heated equipment (such as flue-type waste heat boilers, etc.) within the scope of application for defense or military equipment.
Normal operation maximum working pressure is less than 0. 1MPA pressure vessel (including in the process of feeding or material to be subjected to instantaneous pressure greater than until 0. 1MPA pressure vessel, excluding disinfection, cooling and other processes in the need for a short time to withstand pressure greater than or equal to 0. 1MPA pressure Vessel).
The air separation plant sold by our company to Turkish customers has been successfully installed. Now the equipment is being commissioned.
The nitrogen plant sell to our Italy client is successfully delivered in this month; The unattended nitrogen plant supplied by Suzhou Xinglu Air Separation Plant Science and Technology Development Co.,Ltd can apply for many purpose, such as use the nitrogen as protection air, material air, purging air and sealing air etc.
In terms of the development of large-scale air separation plants in China, the number of large-scale air separations has reached an absolute majority in the world. The ratio of 60,000-class air separations to global air separation is greater than 75 percent; the domestic monomer scale has reached 100,000-scale. In the market demand of the past three years, the proportion of extra-large air separations accounted for the vast majority.
The characteristics of the construction of air separation plants in China in recent years are as follows:
First, attach importance to the stability of equipment units, because it limited by the conditions of transportation and installation is difficult.
Second, the equipment installation time is short, there are loopholes in management.
Three, Some areas in which the environment are poor, such as serious pollutants in the chemical industry area, lack of water, and large sandstorms in the northwestern region.
Fourth, the difference level of installation team is uneven.
Five, the demand for coal chemical industry is high, the demand for iron and steel metallurgy is low, the coal chemical industry is more concerned with stability, and steel is more concerned with the energy saving of operation.
Six, The relocation of the iron and steel industry has created a new wave of demand, but the overall volume is small, and the energy-saving transformation has increased.
With the rapid development of modern technology, the future development of air separation equipment will show the following trends:
First, large-scale, clustering;
Second, the core technology gradually localized;
Third, refinement, for different application areas, the need to develop and match with efficient energy-saving process;
Fourth, highly automated, intelligent (such as automatic load change, reduce product release rate, minimize manual operations, the use of high-speed Internet technology to gradually establish a remote monitoring system, real-time collection of air separation equipment operating data, the use of big data analysis Give users the best advice, etc.)
Professor Li Huazhi, a senior expert in the field of metallurgical oxygen production in China, pointed out that the metallurgical oxygen industry should pay attention to the following aspects:
First, we must focus on operational optimization, attach importance to environmental issues, and closely link production operations with the environment.
Second, we must pay attention to practical energy-saving transformation.
Third, the oxygen plant of iron and steel enterprises should pay attention to the future development trend.
The adsorbents usually used in the industry include: the Silica gel ,active alumina, activate carbon molecular sieve and etc. Moreover, there are also other adsorption material as per some composition selective adsorption, whether the air can be successfully adsorbed, it is mainly depended on the adsorption performance, so the adsorbent selection is the first issue for the adsorption confirm.
Active aluminium oxide is made from the Aluminum hydrates are heated and dehydrated. Its performance is depended on the preliminary state form the hydroxide, it is usually not the pure Al2O3,Partially hydrated amorphous porous structural material.In which there are not only amorphous gels but also crystals of hydroxide.It has strong affinity for water and is an adsorbent for deep drying of trace water. Under the definite condition, the dry degree can be minus 70deg c of the dew point.
The zeolite molecular sieve is called the zeolite and also called molecular sieve. Its chemically composition as follows: [M2(Ⅰ)M(Ⅱ)]O.Al2O3.nSiO2.mH2O.
The zeolite has a function of molecular sieve, it has a uniform pore diameter, such as the fine pore of 3A0、4A0、5A0、10A0.The 4A0 zeolite with 4A0 pore size can adsorb methane and ethane without adsorbing the n-alkanes with more than three carbons.It has been widely used in gas adsorption separation, gas and liquid drying and the separation of isoalkane.
With the rapid development of China’s economy, the importance and role of industrial gases in the economy have become increasingly prominent. As an important basic raw material for modern industry, gas products have a wide range of applications.
Industrial gases mainly include oxygen, nitrogen, argon, helium, neon, krypton, xenon, hydrogen, carbon dioxide, acetylene, natural gas, etc., involving all aspects of industry. The industrial gases mentioned in this paper mainly refer to the ability to separate and obtain oxygen, nitrogen, and argon through air filtration equipment. Rare gases such as helium and neon can also be obtained by further purification.
Preparation of oxygen, nitrogen, and argon is mainly achieved through air separation equipment. Large-scale air separation equipment is mainly used in coal chemical, fertilizer, petrochemical, metallurgical industries, and IGCC power generation enterprises, while small and medium-sized air separation equipment is mainly used for small and medium-sized metallurgy, Chemicals, building materials, electronics companies.
At present, there are two models for large-scale industrial gas use in China: one is for self-construction, air separation equipment companies only provide equipment, and the other is for outsourcing model, which directly allows air separation equipment companies to invest and build factories in the plant area. Provide gas for the company. With the strengthening of industrial gas market, more and more outsourcing models will be applied.
Would you like to know how to manufacture the industrial rare gas? Although the industrial gas is usually the nitrogen, but it not as rare gas. Nitrogen is air separated, rectified from the air cryogenic liquefied, then the nitrogen and oxygen can be got etc.
Helium is mainly from the natural gas, because its content in the air is too little, some mineral resources of the natural gas contain much Helium. It can be air separated by liquefaction, Helium is one kind of rare resources, it is really little in the earth, it is basically non-renewable resources, the price is increasing recent years.
Certainly, Helium is also got form the air separation, because Helium and neon are really difficult to liquefaction, the small amount of Helium and Neon mixture can be got from air after liquefaction, Helium and Neon can be got form the further separation.
A lot of people do not know what kind of other usage except the inflatable ball, but a lot of analyzers being used on science will use the Helium.
Neon is mainly used on neon light filling, it is mainly manufactured by air separation, although its concentration is really little.
The Argon content is rich in the air, (which is close 1%), it can be easily got from the air separation. So, it is really cheap as a protective gas. This is the reason why the argon arc welding is often to be seen, while not the Helium arc welding or the Neon welding.
From March 19th to March 24th in 2018, The Italy Italy Customer came to visist XLA. During this trip, They visited Yi chuan &Xishui Plant site in China. They spoke highly for the two plants。They visited the workshop in XLA. They approve the air separation plant of XLA. They considered the technology from design to manufacturing of air separation plant by XLA is vey mature and XLA also accumulated a lot of experience in this industry, which will get a higher level in the air separation industry.
The air separation unit adopts cryogenic technology, which uses oxygen and nitrogen gas to separate gas at different boiling point under the same pressure to extract oxygen, nitrogen and other gas components in the air. At present, the main air separation processes are divided into internal compression processes and external compression processes.
Most of the newly designed air separation units use the DCS control system. The DCS control system better realizes the chain protection and anti-surge control of air compressors, the sequence control of molecular sieve systems, and other conventional controls. The implementation of the DCS system has smoothed the operation of the equipment to some extent, and improved the control level of the equipment.
In order to achieve automatic variable load control and multivariable predictive control, and to achieve a better control effect, attention should be paid to the following aspects to ensure the optimal control system operation.
The performance of the air compressor can avoid entering the anti-surge zone during low load operation, and the inlet guide vane has good control of rapidity and stability.
The distillation tower ensures high stability in the full load range.
Instrument selection and design of adjustment control system minimizes measurement lag and guarantees the accuracy of continuous inspection.
The requirement of accuracy and rapidity of field instruments are relatively high.