ASU

Your Professional ASU Supplier

Suzhou Doer Gas ＆Chemical Equipment Co., Ltd. Was established in 2009 and is located in Xiangcheng District, Suzhou. It is a high-tech enterprise integrating R&D, design, manufacture, complete engineering, industrial services, and investment operations. The company has a registered capital of 100 million yuan, has 6 subsidiaries, two production bases with a total area of about 135,000 square meters, and a total number more than 400 employees.

Our Product
Large Scale Atmospheric Cryogenic Storage Tank, Vacuum Cryogenic Liquid Storage, Cryogenic Liquid Transportation Equipment, LNG Marine Equipment, Turn-key project.

Production Market
Suzhou Doer Gas ＆ Chemical Equipment Co., Ltd. is a comprehensive solution provider and service provider that integrates low-temperature technology research and development, design, equipment manufacturing, engineering general contracting, industrial services, and investment and operation.

Production Equipment
Electric single beam crane, bridge crane, Laser cutting machine, Inverter DC arc welding machine.

Large/Middle Size Air Separation Unit
Function: Product required gaseous and liquid oxygen, nitrogen, argon helium, neon, krypton and xenon
Technology: Inner Compression, External Compression, Self-pressurizing...
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Full Liquid ASU
Function: Product required liquid oxygen, nitrogen and argon
Technology: Air direct expansion, medium pressure cycle single expansion, medium pressure cycle single expansion + air chiller...
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High-purity Nitrogen ASU
Function: Produce nitrogen products with required purity
Technology: Inner Compression, External Compression, Single Column Process, Double Column Process, and Double Column with Pump...
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Oxygen & Nitrogen Liquefier
Function: Liquefie and store gaseous oxygen, nitrogen, and argon.
Technology: medium pressure cycle single expansion process, medium pressure cycle single expansion + air chiller process,...
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Large/Middle Size Air Separation Unit

First of all, the large and middle size air separation plant is fit for the medium gas company, steel plant, and non-ferrous metal smelting plant, the petrochemical company, glass factory and paper mill, coal power plant, shipbuilding factory and heavy machinery factory. Furthermore, it may serve as professional industrial oxygen and nitrogen generator, chemical oxygen generator and medical oxygen generator, etc.

Product Parameters

Products	Capacity (Nm³/h)	Purity (vol)	Pressure out of cold box MPa (G)	Temp. out of cold box (℃)
GOX	150～80000	≥99.6%O₂	According to requirement	Normal Temp
GAN	0～200000	≤10ppmO₂	According to requirement	Normal Temp
LOX	50～10000	≥99.6%O₂	～0.15	Saturated or supercooled
HP-LOX	According to requirement	≥99.999%O₂ £ 2ppmAr £ 5ppmN₂	～0.15	Saturated or supercooled
LIN	0～10000	≤10ppmO₂	～0.5	Saturated or supercooled
LAr	0～3000	≤1.5PPmO₂ ≤4PPmN₂	～0.15	Saturated or supercooled
Crude Krypton-xenon concentrate	0～200	According to requirement	～0.1	Saturated or supercooled
Crude Neon-helium concentrate	0～15	Ne+He≥60%	～0.4	Normal Temp

Note: The liquid product pressure is measured at 0 meters elevation of the cold box, considering the static pressure of the liquid column.

Working Principle

No	MAIN PART	FUNCTION
1	Air Compression System	After the raw air is filtered, it is compressed to ～0.5 MPa by the air compressor.
2	Air Booster System	Provide medium pressure expansion gas source for the device and absorption the cooling capacity of medium and high pressure liquid oxygen (nitrogen), generally used for internal compression process.
3	Pre-cooling System	Reduce the temperature of compressed air to about 8～10 ° C
4	Purification System	Removing the remained moisture, carbon dioxide and hydrocarbons of compressed air in the molecular sieve adsorber.
5	Distillation System (Cold Box)	Distillation system is the key to realize air separation. It mainly uses the boiling point difference of oxygen and nitrogen (argon), and uses the process of partial vaporization and partial condensation many times to make the low boiling point components continuously evaporate from the liquid phase to the gas phase, and at the same time, the high boiling point is continuously condensed from the gas phase to the liquid phase, and finally realizes the separation of oxygen and nitrogen (argon).
6	Turbo Expander System	The air expands in the turbine expander, to provides the cooling capacity required by the device.
7	Storage and vaporization System	Store the separated liquid products, such as liquid oxygen, liquid nitrogen, and liquid argon.
8	Instrument Control System	The entire air separation unit is equipped with a central control system to monitor, control and interlock the process parameters of the entire air separation unit (air compressor, air booster, pre-cooling system, purification system, turbine expander, distillation system, liquid storage and vaporization system). The own control system for machine unit communicates with the air separation unit control system by Modbus, so that its operation status can be monitored at the operating station in the central control room.
9	Electrical Control System	The electrical control system provides power for the electrical equipment of the air separation unit. A reasonable and optimized power supply and distribution system design can not only reduce investment and loss, but also be the cornerstone and guarantee for the reliable operation of the air separation unit.

Technical Features

Full Automation

All systems are designed for un-attended operation and automatic Nitrogen demand adjustment.

Lower Space Requirement

The design and Instrument makes the plant size very compact,assembly on skids,prefabricated from factory.

Fast Start-up

Start-up time is only 5 minutes to get desired Nitrogen purity. So these units can be switched ON&OFF as per Nitrogen demand changes.

High Reliabiity

Very reliable for continuous and steady operation with constant Nitrogen purity. Plant availability time is better than 99% always.

Molecular Sieves life

Expected Molecular sieves life is around 15-years i.e. whole life time of nitrogen plant.So no replacement costs.

Adjustable

By altering flow,you can deliver nitrogen with precisely the right purity.

Process Description

Air Compressor
Atmospheric air enters into compressed from suction filters to remove dust from it and compressed from atmospheric pressure to 20 bar-g. Compressed air must be conducted by intercoolers interstage cooling and after leaving compressor it goes to aftercooler.

After Cooler

Compressed hot air cool down up to 35-40 0C in after cooler by cooling water.

Waste Nitrogen Cooler
Waste nitrogen exchanger is direct contact type of cooler. In waste nitrogen cooler, waste nitrogen from cryogenic ASU plant cooled down hot water up to 10 – 30 o C.waste nitrogen tower has a robust construction design to withstand high pressure and temperature. Internal of waste nitrogen cooler provide increased efficiency and reliability.

TSA Skid
Cool air enters into purification unit that is TSA skid to remove water and CO2 from air. Molecular sieve in TSA column absorb moisture and CO2 form air.

MHE And Expander
Pure air Cooled in aluminium brazed plate fins heat exchanger (MHE) and pass through expander to achieve cryogenics.

HP Column
Liquefied air separated into gas and liquid in HP column. Oxygen enriched liquid separate out from bottom of HP column Top nitrogen gas from HP column pass through re boiler/condenser converted into liquid nitrogen and sent to LP and HP column as reflux, to liquid nitrogen storage tank.

LP Column
Oxygen enriched liquid from HP column sent to LP column as reflux for distillation purpose and purified liquid oxygen separate from bottom of column from condenser/re boiler and purified low pressure nitrogen gas from top.

Argon Column
Argon fraction (8-10% argon) taken from bottom side of LP column and sent into crude argon column and argon column where first oxygen gets separated from stream and then remaining nitrogen separated out and liquid argon separated from bottom side of argon column

Necessary Conditions before Starting the Air Separation

The construction of all piping, machines and electric devices has been completed and accepted.

All safety valves have been set and put into service.

All the manual valves and pneumatic valves should act flexibly and all the adjusting valves should be commissioned and calibrated.

All the machines and instruments are in good performance and are prepared for service.

The program control system of the molecular sieve purifier have been commissioned and ready for service.

Power supply is ready.

Water supply is ready.

Instrument air supply is ready.

Working principle

Fractionation tower heating, cooling, liquid accumulation and purification in one go, simple and fast operation. Using aluminium plate fin heat exchanger, aluminium convection sieve tower, the whole fractionation tower equipment pipeline using argon arc welding, cold box tower and the main pipeline, using high-strength aluminium alloy material or stainless steel material, in order to increase the strength, reduce the torsional damage of the pipeline. Cold box equipment bracket, pipeline and valve bracket should be used stainless steel or aluminium alloy material. The cold box is insulated with pearlescent sand and slag wool to ensure minimum cold loss. The structure of the cold box ensures the overall strength and requirements of earthquake and wind resistance to ensure the load-bearing capacity of the cold box; the cold box is equipped with sealed gas protection and safety devices during operation; the main equipment in the cold box is set up with electrostatic grounding; the cold valve and pipe connections in the cold box are all welded, avoiding the use of flange connections.

Supporting Unit

Centrifugal air compressor.

Air precooling system.

Purification system.

Booster turbine expansion unit.

Distillation column system.

Liquid storage system.

Nitrogen compression system.

Oxygen compression system.

Instrument control system.

Electronic control system According to the needs of users, various specifications of gas products can be provided.

Certificate

productcate-1-1

FAQ

Q: Wonder if you accept small orders?

A: Do not worry. Feel free to contact us .in order to get more orders and give our clients more convener ,we accept small order.

Q: Can you send products to my country?

A: Sure, we can. If you do not have your own ship forwarder, we can help you.

Q: Can you do OEM for me?

A: We accept all OEM orders,just contact us and give me your design. We will offer you a reasonable price and make samples for you ASAP.

Q: What's your payment terms ?

A: By T/T,LC AT SIGHT,30% deposit in advance, balance 70% before shipment.

Q: How can I place the order?

A: First sign the PI,pay deposit,then we will arrange the production. After finished production need you pay balance. Finally we will ship the Goods.

Q: When can I get the quotation ?

A: We usually quote you within 24 hours after we get your inquiry. If you are very urgent to get the quotation.Please call us or tell us in your mail, so that we could regard your inquiry priority.

We're well-known as one of the leading asu manufacturers in China. If you're going to wholesale high quality asu made in China, welcome to get quotation from our factory.