Preface
Traditional oxygen process, foreign compression process applied at home and abroad
Was more common. With the traditional external compression process compared to flow within the compressed
The principle of process in the oxygen there is no fundamental difference, the main difference between the two
The craft is equipped with different kinds of processes, as well as the oxygen out of the cold box status is not
The same. Outside the compression process, a cold box of the oxygen status of low-voltage state,
Pressurized oxygen through the oxygen compressor to 310MPa, and then sent to the
Users. The compression process is to pump the liquid oxygen through the liquid oxygen pressure to the
The required pressure, and then in the cold box in the main heat exchanger and through the
Air Booster Booster after the high-pressure air heat exchanger to cool at room temperature after a
Box directly for the user.
In recent years, with the production scale of the constantly increasing, the need of oxygen
Constantly increasing demand, the installed capacity of air separation equipment, along a corresponding increase
Great. For large-scale air separation plant is concerned, associated with a temporary shortage of domestic
Sets of large-scale production capacity and experience of the oxygen compressor, and from the country
The introduction of oxygen compressor outside the match, with a corresponding subject to production week
Period, investment costs, and spare parts and many other factors. Because
This, the recent large-scale air separation plant in the country sets in, more selection
Used within the compression process. Within the compression process an air separation plant oxygen removed
Compressor, the addition of air pressure device, liquid oxygen pumps and high-pressure main heat exchanger
Etc..
According to Tianjin Iron & Steel Co., Ltd. (hereinafter referred to as: days steel) Lian
Iron and steelmaking production, the need for additional oxygen, nitrogen and argon gas
Supply. Line process is stable, advanced technology, equipment reliability and
Investment savings principle, been fully discussed and repeatedly demonstrated, Tin Steel
Finally decided to build two 28000m3 / h Air grouped within the compression process
Prepared. Of these two air separation plant air separation plant by the Chinese company's total contracting,
Operation of equipment, imported equipment including ordering, air purification and distillation column system
Commission Order Hangzhou Oxygen Machine Corporation (hereinafter referred to as: Hang oxygen) is located
Prepared. In September 2003 signed a general contract and equipment orders All
Tong, began construction in March 2004 construction began in October 2004
Equipment installation, in August 2005 and September has two air separation plants transferred
Test proved successful, put into operation.
An air separation equipment, technical parameters and processes
Tiangang 28000m3 / h Air Separation Plant in the main technical parameters of Table
1, the process shown in Figure 1.
Table 1 Tiangang 28000m3 / h Air Separation Plant for technical parameters
Products
Yield / (m3 / h)
Conditions for case Ⅰ Ⅱ Ⅲ conditions
Purity Pressure / MPa Temperature / ℃ Remarks
Oxygen 27000 29000 28000 ≥ 9916% O2 310 34 within the compression
LOX 2300 300 1300 ≥ 9916% O2 011 - 176
Nitrogen 28000 28000 28000 ≤ 5 × 10 - 6O2 0107 34
Pressure of nitrogen 1000 1000 1000 ≤ 5 × 10 - 6O2 0145 34
Liquid nitrogen 800 1800 1800 ≤ 5 × 10 - 6O2 012 - 190
Gas Argon 580 1100 ≤ 2 × 10 - 6O2, ≤ 3 × 10 - 6N2 310 34 within the compression
Liquid argon 600 1100 ≤ 2 × 10 - 6O2, ≤ 3 × 10 - 6N2 011 - 179
Table 1 in the working conditions for the air separation plant Ⅰ assessment indicators, working conditions
Ⅱ, Ⅲ condition indicators for the variable condition. Oxygen as an internal compression, directly by
Pressure to 310MPa send cold box; nitrogen cold box for the low-voltage sent; argon
For parts of gas compression, pressurization to 310MPa sent cold box for use
Household use, partly in the form of liquid argon into the liquid tank; liquid oxygen and
Directly into liquid nitrogen tank.
Two main device configuration
211 Air Filter
Air filter with Beijing produced by Colin Green
LDMK21530KL type bag filter, filter gas:
200000m3 / h, the filtration resistance: 018 ~ 112kPa, filter precision:
≤ 2μ, filter materials, imports of acupuncture use it. This filter
Fig 1 day steel 28000m3 / h Air Separation Unit within the compression process flow diagram of
Benefits: Filter area, filter velocity is relatively low, the air suction pressure
Power loss. When the bag high resistance, by the automatic control system of the input
Into the cleaning pressure of the air, blowing the dust bag attached, bag by
After blowing off can be reused. And the self-cleaning filter compared to the
Although the one-time investment in equipment filters more, but the use of the cycle and
Long life, and the use of the maintenance, overhaul small amount of work.
212 air compressor
Air compressor (hereinafter referred to: air compressor) using MAN,
Production RIK901-type single-axis turbine compressor, four three times in the
Inter-cooling, air flow: 147000m3 / h, discharge pressure:
0163MPa (A). Compressor a "constant pressure" control the gas delivery
A pipeline installed shorting bypass anti-surge valve, venting valves to meet the air compressor
The whole volume of shorting capabilities. Control signal is converted to 4 ~ 20mA current letter
Enter No. DCS system, automatic control by the system.
213 air-precooling system
Air pre-cooling system consists of Hangzhou oxygen production, handling air quantity:
147000m3 / h, working pressure: 01615MPa (A), the air into the tower
Temperature: 100 ℃, the air out the tower temperature: 17 ℃. Is equipped with two high -
Temperature water pumps, two low-temperature water pumps, air-cooling towers and cooling tower are packing
Tower. Hot in the summer season freezer configuration to meet the cooling water temperature
Requirements.
214 molecular sieve purification system
Molecular sieve purification system for the Hang oxygen production HXK2147000 / 5
Type, processing gas: 147000m3 / h. Molecular sieve adsorber for the horizontal
Double-bed structure, were filled with two kinds of molecular sieves and alumina adsorption
Agent, to purify the air in the water, carbon dioxide and hydrocarbon
Materials and other impurities, molecular sieve adsorber regeneration of nitrogen pollution from the reflux.
215 Booster air compressor
Booster air compressor manufactured using ATLAS
GT050L2K1PGT026L2K1-type compressor, four band for the biaxial
-Axis, multi-use air-pressurized aircraft. By two out of part of the gas into the
Turbo-expander system, four exhaust gas through the plate-fin heat exchanger for
Heat, cutting into the next tower. Unit two-part gas are a "constant
Press "control, respectively, in each part of the air exit is set back anti-surge
Valve, return valve to meet 100% of their ability to return.
216 supercharged turbo-expander
Pressurized turbo-expander expansion side inlet pressure 2188MPa
(A), discharge pressure 0158MPa (A); pressurized side inlet pressure
2116MPa (A), discharge pressure 21916MPa (A). Turbine expansion
Machine configuration is only one Taiwan, flow rate adjustment range can be ± 20%. Turbine Expansion
Inflation adjustment machine back through the pressurized side of the bypass valve to control, expansion of
After the gas directly into the next tower.
217 Distillation System
In addition to the sieve-plate column under the tower structures, the tower and crude argon Ⅰ, Ⅱ tower
All of structured packing and distillation tower, crude argon column Ⅱ Ⅰ with the crude argon column
Between the pump by circulating liquid argon argon to keep the system continuously.
Expander, after expansion into the gas directly under the tower, the participation of fine tower
Distillate, pressurized gas cutting machine after the end of the next tower.
218 medium-pressure liquid oxygen pump
Medium-pressure liquid oxygen pump for centrifugal liquid pumps, installed in the cold box
Inside, equipped with two, one with a prepared; drive motor with frequency conversion devices,
Adjustable liquid pump working conditions.
219 Nitrogen Compressor
Nitrogen compressor (referred to as: nitrogen press) using the public Ingersoll-Rand
Division C125MX5N2 suction single stage, single-stage exhaust and five pressure
Reduction of the centrifugal compressor, exhaust flow: 20500m3 / h. Whole
Unit, including mainframe, cooling systems, lubrication systems, and other auxiliary
Equipment, are arranged in a common chassis, the structure is very tight
Cou.
2110 Liquid Storage and Transportation System
The two sets of air separation plants sharing a set of liquid storage and transportation system that uses ordinary
Press flat liquid tank, 2000m3 liquid oxygen tank one Taiwan, 1200m3 liquid
Nitrogen, liquid argon tank of a station. Storage of liquid both for export, reduce
Low-oxygen of the comprehensive cost, but also can be used as an alternate for the production of gas
Equipment, once the operation of equipment failure, through the liquid pump pressure steam
Of added pipe network for steel making, iron gas.
2111 DCS System
Wang Hexi instrument control system uses the company's CS3000-based DCS
System. DCS system includes all the equipments above the pressure
Force, temperature, flow, liquid level measurement, control and regulation. Two
Air separation plant is divided into two DCS systems. In addition, two sets of air grouped
Preparation of public facilities including the circulating cooling water pump house, the gas pressure regulator sent
Systems and liquid storage and transportation system, a separate set up a DCS system.
In order to prevent the two air separation plant operation between the errors to occur, in the set
Meter in the system control. In addition to numbers differ, the
In the control system do not operate each other. CS3000 DCS system
Integration with Windows XP operating system, can provide a complete full -
Foot required software, including the actual operating system, applications
And historical records.
Three characteristics of an air separation plant process
(1) within the compression process an air separation plant, the biggest advantage is its full
Of facilities and safety performance greatly improved. Cryogenic liquid oxygen pump to replace the operation
The high-pressure oxygen compressor. Oxygen is the use of speed turbine compressor
So that pressurized oxygen to achieve the purpose, so large-scale air separation equipment, supporting
Large-capacity oxygen compressor is bound to be high speed. And the oxygen itself is
A combustion-supporting gas, in case of high temperature or other accidents, will be oxygen pressure
Machine incalculable loss. Cryogenic liquid oxygen pump in low temperature, low-turn
Operating speed operating conditions, using liquid oxygen pump to replace the oxygen compressor can be hidden safety
Suffering from reduced to a minimum.
(2) The compression process in process with no external compression is also a slight
The same. Outside the compression process, oxygen in the main cooling tower in liquid nitrogen and lower heat transfer
Vaporization in the form of gas flow after distillation column. With the device run-time
Between the extension of the main cold liquid oxygen will be different levels of hydrocarbons in the
Enrichment, accumulation, the safe operation of the equipment is also a potential
Hidden. In order to ensure security, tend to adopt emissions 1% of the oxygen of the
Of liquid oxygen to reduce the possibility of liquid oxygen in the accumulation of hydrocarbons. Internal compression
Process within the main condenser air separation equipment, liquid oxygen can reach 100% oxygen
The liquid oxygen emissions, so that hydrocarbons can not be the main cold accumulation, from the
Process further to ensure the overall safety of equipment operation.
(3) The compression process cryogenic liquid oxygen pump configuration, since it is
Low temperature, low-speed running state of the equipment under normal circumstances may be
In continuous operation 20000 h, and the craft are equipped with two liquid oxygen pumps
Taiwan, in the production operation with a prepared one. Configuration suits the compression process
Preparation of oxygen compressor would not be possible to configure machine. Therefore, the liquid oxygen within the compression process
Pump configuration makes the device operation reliability greatly increased.
(4) within the compression process due to the configuration of the pressurized air craft
Compressor, a high-pressure air as a booster machine expander of raw materials,
Can give full play to the role of expansion refrigeration machines, fully meet the air grouped
Preparation of the cooling capacity requirements. Into the expander through the pressurized side of the air by
Pressure, the pressure can reach 219MPa (A), corresponding to a Expander
The air pressure also increased, reaching 0158MPa (A). Thus, swelling
Expansion of air can directly enter the next tower, from the process the organization has improved precision
Distillation tower adjustment range can be significantly adjusted to variable operating conditions.
(5) within the compression process an air separation plant due to configuration of the booster machines,
Makes the expansion cooling capacity greater gas production to meet the circumstances,
Can produce the largest quantity of liquid. The traditional outer space grouped compression process
Preparation, can only extract the oxygen output of 1% ~ 2% of the liquid volume. Table 1
As can be seen inside the compression process of liquid air separation unit volume up to
To extract oxygen production to 13%, this alone can increase the air separation
Comprehensive benefits of equipment and reduce overall energy consumption.
(6) configured within the compression process increases oxygen booster pump air compressor
Machine, instead of oxygen compressor. Oxygen compressor, either from the manufacturing process or the
Equipment structure, than those in Booster complex equipment manufacturing cost will be
Higher than the liquid oxygen pump and the sum of these two booster aircraft, and the oxygen in the Japanese press
Regular maintenance and replacement of spare parts in machine cost will be higher than the supercharger
And the liquid oxygen pump.
The installation of the device, the past presses in the engineering design of oxygen
Adopt two-tier arrangement, in the same device, oxygen compressor plane accounted for
Land area is also great Bizeng press. Booster generally in engineering design
Using single-layer arrangement, liquid oxygen pumps are arranged in the cold box of the iceberg. Because
The building project, if the factory area is subject to constraints, pressure machine
Oxygen compressor to install than a clear advantage there.