Home >> Industry Knowledge >> Nitrogen Generator (Nitrogen equipment) of the Development and Operation
1 Overview
Yongcheng coal-fired electricity (Group) Co., Ltd. (hereinafter referred to as:
Coal Wing) coal chemical project is based on coal as raw material, the use of
SHELL coal gasification technology, an annual output of 500,000 t of methanol in large-scale chemical . Coal Chemical Industry in accordance with the process technology and a comprehensive user requirements, the need
Oxygen capacity allocation for a set of 53000m3 / h air separation plant. Yong
Open tender Coal Group, Kaifeng Air Separation Group Co., Ltd. (hereinafter Jane
Said: Kaifeng Air Separation) to the successful cost-effective, in December 2004
Supply contract entered into on the 8th. November 28, 2007,
53000m3 / h air separation plant to produce a smooth passing of oxygen, nitrogen
Gas, in May 2008 to produce liquid argon qualified. ASU to open
Car goes well, the success of the first test, and successfully pass the examination are air separation
Normal operation of production equipment.
Coal Wing 53000m3 / h air separation plant is currently the self -
Line sets, and independent design and manufacturing and has been put into operation the largest
Within the compression process an air separation plant. Air separation plant using advanced technology
Processes, the chemical industry is a typical double-pump compressed air separation process .
2 The main performance indicators
According to Yong Coal gasification plant product specifications for the gas to
Seek, 53000m3 / h air separation plant design, there are two operating conditions, the
The main performance indicators are shown in table 1, 2.
Table 1 normal conditions 53000m3 / h air separation unit main technical indicators
/ (M3 / h)
/ MPa
/ ℃
Oxygen 52000 ≥ 9916% 511 37
Oxygen Tank
Pressure of 511MPa
Oxygen 1000 ≥ 9916% 0125 Saturation --
Nitrogen (1) 32000 ≤ 10 × 10 - 6O2 015 19 under the pressure of nitrogen tower
Nitrogen (2) 11000 ≤ 10 × 10 - 6O2 813 37 compressed liquid nitrogen pump
Liquid nitrogen 800 ≤ 10 × 10 - 6O2 0145 Saturation --
Liquid argon 1600
≤ 1 × 10 - 6O2,
≤ 2 × 10 - 6N2
Saturation 0125 --
Instrument Air 2500
Atmospheric Dew Point:
- 40 ℃
111,540 booster pumping machine
Factory Air 5000
Atmospheric Dew Point:
- 40 ℃
Molecular sieve adsorber
After taking the
Nitrogen accident 11000 ≤ 10 × 10 - 6O2 813 40 --
Note: The pressure gauge, the same below.
Table 2 gasification conditions 53000m3 / h air separation unit main technical indicators
/ (M3 / h)
/ MPa
/ ℃
Oxygen 46000 ≥ 9916% 511 37
Oxygen Tank
Pressure of 511MPa
Oxygen 1000 ≥ 9916% 0125 Saturation --
Nitrogen (1) 32000 ≤ 10 × 10 - 6O2 015 19 under the pressure of nitrogen tower
Nitrogen (2) 11000 ≤ 10 × 10 - 6O2 813 37 compressed liquid nitrogen pump
Nitrogen (3) 38000 ≤ 100 × 10 - 6O2 0102 19 on the tower of low pressure nitrogen
Liquid nitrogen 800 ≤ 10 × 10 - 6O2 0145 Saturation --
Liquid argon 1400
≤ 1 × 10 - 6O2,
≤ 2 × 10 - 6N2
Saturation 0125 --
Instrument Air 2500
Atmospheric Dew Point:
- 40 ℃
1115 40 --
Factory Air 5000
Atmospheric Dew Point:
- 40 ℃
0154 40 --
Note: Gas Chemical status refers to coal gasification plant in the car, not for losers
Delivery of coal carbon dioxide gas, air separation plant temporarily out of the tower
38000m3 / h instead of nitrogen.
3 Process Organization
Indicators in accordance with contract requirements, energy consumption, investment costs,
Security and interoperability and so on can be considered, 53000m3 / h Air
Separation plant selected molecular sieve adsorption to purify the air pressurization through
Central, under the expansion of air into the tower, double-pump compression and full-distillation hydrogen-free
Argon flow, that is, pressurized air machine + oxygen (N) pumps, and Qualcomm
Heat exchange system have been replaced by the rational organization of oxygen (nitrogen) press. Oxygen
(52000m3 / h, 511MPa), after pressure from the liquid oxygen pump hot Rehabilitation
That nitrogen (11000m3 / h, 813MPa) pressurized by the liquid nitrogen pump
Received after the resumption of heat, nitrogen (32000m3 / h, 015MPa) from the next
Direct extraction of nitrogen pressure tower complex to be hot. Therefore, the raw material air compressor
Discharge pressure to 01575MPa, air compressor displacement to
276000m3 / h. Coal Wing 53000m3 / h Air Separation Plant Process
As shown in Figure 1.
Raw materials by air compression, cooling and purified, divided into two:
Enter a low-pressure plate-fin heat exchanger, a heat exchanger at the bottom into the next
Tower; pressurized air to another machine. Machine into the air pressurized air
Pressurized by the supercharger drive to the first paragraph after about 216MPa is divided into two units: a
Unit direct a pressurized machine, cooled by the cooler into the expander by
Pressure-side booster, then cool to room temperature after the cooler into the high-pressure plate
-Fin heat exchanger heat exchanger, heat exchanger and then out into the expansion of the central
Airport expansion, after expansion of the air into the next column; another by air in
Pressurization of the second paragraph of the press continue to 7MPa, and the post-cold cooler
To room temperature after they entered the high-pressure plate-fin heat exchangers, and high-pressure liquid oxygen,
High-pressure liquid nitrogen and nitrogen pollution reflux exchanger. This part of high-pressure air from high
Plate-fin heat exchanger at the bottom out, after cutting into the next tower.
Under air by the preliminary distillation tower, the fluid was air, pure nitrogen and
Nitrogen pollution, and after-cooler cooling towers expenditure entered. By the tower
After further distillation, to obtain in the liquid oxygen at the bottom of the tower, and by the liquid oxygen pumps
Compressed into the high-pressure plate-fin heat exchanger, in which hot liquid oxygen complex
And after the vaporization of oxygen into the cold box, enter the high-pressure oxygen pipe network; another draw
Get some oxygen into the liquid oxygen storage system. At the top of the next tower to obtain pure
Liquid nitrogen, and compressed by the liquid nitrogen into the high-pressure pump plate-fin heat exchanger,
In which heat and vaporize liquid nitrogen complex after nitrogen into the cold box, enter the high -
Pressure nitrogen gas pipe network; also taken part into the liquid nitrogen storage system with liquid nitrogen.
Taking the pressure at the top of the next tower nitrogen, by the low-pressure plate-fin heat exchanger complex
Heat after the cold box, enter the medium-pressure nitrogen gas pipe network. Leads from the top of the tower
Nitrogen, after cooling and low plate-fin heat exchanger after the resumption of the cold heat
Box, enter the low-pressure nitrogen gas pipe network.
4 main support units and equipment
411 air compressor and air pressurization of raw materials machine
Air compressor and air pressurization of raw materials are used centrifugal compressor machines,
Turbine drag from 1 to save the investment and operating costs. Air
Pressurized expansion drive for the devices and high-pressure liquid oxygen, high pressure liquid nitrogen evaporation
The gas source. Air compressor and air pressurization of raw materials are imported production machines
Goods, raw materials for the compressor models RIK (T) 12521 + 1 + 1 +
1, the use of single-axis, 4 compression level cooling, a cantilever, and
The use of built-in cooler; air pressurized aircraft models for the RG5021 + 1
+ 1 + 1 + 1, the use of gear, compression level 5 cooling. Steam
Imported marine products.
412 air-cooling system
Air-cooling system uses water-cooling towers with new high efficiency air pre -
Cooling system. The use of specially designed air-cooling tower packing loose, water-cooling tower
The use of structured packing, heat and mass transfer with high efficiency, flexible operation
And the advantages of small resistance. In addition, taking into account the cycle of the water users
Poor, the upper air-cooling towers and water towers used in circulation, a small amount of pay the
The form of ammonia evaporator set to cooling tower water from the water, using
Air-cooling tower the lower the air temperature, a better device performance.
413 molecular sieve purification system
The role of molecular sieve purification system is the adsorption of water in the air,
Such as carbon dioxide and hydrocarbons such as acetylene, using long-period, double
Layer purification technology, switching system uses an advanced set up without the impact of switching
Dollars. Double-sieve adsorber bed structure, the underlying activity of oxidative
Aluminum bed molecular sieve can be effective protection to extend the service life of molecular sieve.
Dual-tube steam heater plate, run a more secure,
414 Distillation System
Distillation system is 53000m3 / h Air Separation Plant in the core system,
On the tower, the crude argon tower Ⅰ, Ⅱ crude argon tower and the refined argon column are used to fill regular
Column technology materials with high oxygen extraction rate, low energy consumption, technology advanced,
Running a safe, reliable and convenient operation and maintenance. Tajikistan has adopted under the
Large-scale air separation plant for the four-column technology overflow. The expander, high -
Pressure heat exchangers and cryogenic liquid pump is used imported products to ensure that the device
The reliability of operation.
415 liquid back-up system
In order to ensure the safety of the entire system of production, a backup system with 1
Taiwan's flat-bottomed tank 200m3, 1 prepared by low-temperature high-pressure liquid nitrogen cooling pump
And 1 in a water bath-type carburetor.
5 General Layout
Coal Wing 53000m3 / h Air Separation Plant larger, the
Unit equipment, valves and pipe specifications, such as a number of bigger,
The design process to meet the prerequisite, as far as possible, so that distillation column layout
Reasonable, compact.
(1) under the tower (the main cold), the composite layout of the vertical tower. Such
While the cold box arrangement than under a high tower (the main cold), parallel to the tower cloth
Home, but save the liquid pump, so to simplify the process, the reliability of reference
High. The past under an air separation plant cooling tower and main factory are complex, consider
To the sets of air separation equipment for the road or rail transport, the transport of objects to allow
Shipping size is not large, in the design of this when asked to pay particular attention to
Title. After Yongcheng Kaifeng along the road to study the situation with
The design, manufacture and transportation of the tripartite coordination to determine the special delivery
Transmission methods, in order to ensure the cold under the tower and the main factory complex, to the scene in place
After the previous tower complex.
(2) low pressure air separation equipment, high pressure heat exchanger two groups, in order to be
In the installation, maintenance, set up a separate cold box, respectively, and separated from the main cold box
Open. In order to prevent the main junction box of cold steel shrinkage at low temperatures change
Shape, heat exchanger cold box and the main cold box used to connect the bridge.
(3) air separation plant a total of liquid oxygen pump, liquid nitrogen and liquid argon pump pump 3
Types of process pumps, are a preparation with a total of 6 (one running, and the other
Preparation of a cold line). Ease of maintenance and safety from the point of view, 6
Taiwan are a separate process pump arrangement, that is, set up a separate small cold box, placed in the main
Outside the cold box.
(4) of some important high-pressure, low temperature liquid valve used alone
The following legislation to allow maintenance.
6 performance
Within 72 hours of testing during the examination, 53000m3 / h Air Separation
Parameters of the working condition of equipment close to the design value, the system running stable,
Frost-free cold box, cold running phenomenon, no internal leakage. Specific test
Nuclear data in Table 3.
7 Concluding Remarks
53000m3 / h air separation plant to drive a successful coal Wing Set
Mission coal chemical projects 500,000 t / a methanol plant has laid a strong driving
Table 3 Coal Group never 53000m3 / h air separation plant assessment data
Products / (m3 / h) the purity of the pressure / MPa
Oxygen 55000 ≥ 9916% 5115
LOX 500 ≥ 9916% 0125
Nitrogen (1) 32500 ≤ 1 × 10 - 6O2 015
Nitrogen (2) 10600 ≤ 1 × 10 - 6O2 813
Liquid nitrogen 2000 ≤ 1 × 10 - 6O2 0145
Liquid argon 1600
≤ 1 × 10 - 6O2,
≤ 2 × 10 - 6N2
The basis of false, set a good example. The open-air separation plant
Cart successful, marks the 50000m3 / h air separation plant level a large country
The middle of the project was a complete success.
Coal Wing 53000m3 / h air separation plant success of the project,
Kaifeng Air Separation is following the Shandong Huaneng Lu Hengsheng Chemical Co., Ltd.
40000m3 / h air separation plant be examined again after acceptance
Compression process in large-scale air separation plant on a breakthrough, marking the space Kaifeng
Points in the large-scale air separation plant and processes within the compression technology has been
Mature, but also signifies that China's space has been fully capable of branch based on its own
, The manufacture of 50000m3 / h within the compression level of large-scale air separation process .
The realization of 50000m3 / h air separation plant level made me
State of air separation equipment design and manufacture of development level and capacity of the
A new level, but also saving a lot of foreign exchange, with
Generate huge economic benefits for families; At the same time can also enhance the country's major
Industrial equipment design and manufacturing level, and have to participate in international competition
The ability to achieve the 80,000 ~ 100,000 m3 / h or more large-scale air separation
Equipment has laid a solid foundation.