CN1916410B

CN1916410B - Multi-stage oil-less gas compressor

Info

Publication number: CN1916410B
Application number: CN2005100926415A
Authority: CN
Inventors: A·阿尔弗德; G·W·克罗姆; J·O·里德
Original assignee: Corac Group PLC
Current assignee: Clarke energy technologies Ltd
Priority date: 2005-08-19
Filing date: 2005-08-19
Publication date: 2010-10-06
Anticipated expiration: 2025-08-19
Also published as: CN1916410A

Abstract

An air compressor of multistage and oil free type consists of dynamic compress or stage of speed variable and motor driven rotation mode being series-connected with water lubricating screw compressor stage at upstream of water lubricating screw compressor, intermediate cooler being set between two said compressor stages for deceasing temperature of air entering into screw compressor stage.

Description

Multi-stage oil-less gas compressor

Technical field

The present invention relates to a kind of multi-stage oil-less gas compressor with intercooler unit.

Background technique

Have many technology that can be used for pressurized gas, every kind of technology raises in total pressure, have its advantage aspect the efficient of available volume flow speed and work of treatment.

Rotation dynamically (rotodynamic) compressor comprises Axial Flow Compressor and centrifugal compressor, and this rotation dynamic compressors can be realized gas compression by the use high speed rotor, thereby improves the momentum of gas, and this momentum is converted into pressure head.When big volume flow need have lessly relatively when entering pressure, this machine is desirable.In order to improve outlet pressure, when keeping acceptable efficient, need bigger rotational speed with respect to other method, this becomes difficult to achieve.These machines normally do not have oily machine, because operation element does not contact with oil lubricant.Importantly, these are handled needs pure air, and in the industry relevant with food with chemistry, any greasy dirt thing can influence main processing.

Another kind of known compressor pattern is the positive displacement helical-lobe compressor, and this compressor comes the pressurized gas volume by driving it by volume between two mutually despun screw rod profiles, that reduce continuously.The profile of screw element is determined the fixing internal pressure ratio of compression stage.But, in this device, also having the composition of the gas external compression that around exhaust port, is produced, this exhaust port makes machine improve compression ratio significantly.

In order to help to seal this system, lubricating contact surface and from compression process, takes away heat, so screw engages is lubricated by oil or water, in this process, utilized again after this last liquid.

In order from air, to remove any oil effectively, therefore need great amount of investment and safeguard filtration system.The major advantage of the screw compressor of water lubrication is, do not think that usually water is pollutant, and the water capacity is easily removed and helped environmental protection.

The compressor of water lubrication is used to refer to the compressor of water injection and the compressor that water overflows here.Difference between these two kinds of compressors is that in the compressor of water lubrication, moisture is turned up the soil and joined in the compressor from handle gas, and in the compressor that water overflows, joins in the compressor to water and processing mixed gases.Water sprays and can produce near isothermal compression gas, thereby has produced efficient compression stage.For this reason, the sliding pressure of the most water profit facility that contract have closed water loops, and this loop comprises opposite permeation and filtration regulating water, thus lubricated continuously simultaneously and cooled compressed element and the gas stream that compressed.

For some years, people know combines so that the optimized performance of combination apparatus two different basically compressor assemblies, for example these are described among the patent GB2034818, although technology at that time is round bigger centrifugal compressor, to produce up to 50000m ³The pressurized gas of/h.Before gas entered the back one-level or leaves this system, traditional interstage cooler and aftercooler device were used for reducing the temperature of low-pressure gas.Typically, these have adopted the shape of shell-and-tube formula heat exchanger, and in heat exchanger, outside supply water is by tubular portion and take away compression heat.Unless they are oversized basically, conventional heat exchanger all has pressure in this system falls, so they can be avoided waste.Therefore they have the relatively poor source of efficient, and are the principal elements of machine overall expenses.

In both cases,, added more compression stage, typically had two compression stages in order to obtain higher pressure.Under the situation of screw compressor, because the character and the complexity of screw rod profile, by guaranteeing to leak size less and that compression efficiency is bigger, available machining validity is come the limit compression machine.This just makes screw compressor more be not suitable for high volume flow.On the contrary, for centrifugal machine, big volume flow and size are preferred.Hour produced difficulty at volume, under the sort of situation, need machine littler, and this machine has turned round with the more high rotation speed that increases, to guarantee enough momentum transfers.This has with balance and bears relevant problem, because the balance validity needs to improve, and speed surpasses traditional ability to bear.

Summary of the invention

According to the present invention, a kind of multistage compressor is provided, this compressor comprises: the electronic rotation dynamic compressors of the speed change first order; The water lubrication screw compressor second level, it is in series with rotation dynamic compressors level at the downstream part of rotation dynamic compressors level; And interstage cooler, it is arranged between this two-stage, thereby reduced the temperature of the gas that enters into the screw compressor level, wherein interstage cooler is that water sprays interstage cooler, the water source of the screw compressor level share common of it and water lubrication is discharged gas and is fed directly in the screw rod level from the water of interstage cooler.

The present invention is in the advantages to of the every kind of oilless compressor structure device, thereby utilized the high speed electric rotor dynamic compressors first order and the partial potential compactedness of screw compressor, these former being disclosed.The high speed rotating dynamic level can provide higher volume flow with the layout of relative compact, so makes it be suitable for the inlet level, and the screw rod level has the ability of regulating the variable inlet condition, and wherein its keeps realizing the constant compression force conveying.In similar two-stage screw type machine, the inlet level is bigger, and volume replaces greatly and with the high speed rotating dynamic apparatus, and the advantage of Time, Cost And Performance can be provided.

The present invention proposes to make water to cool off the gas that directly passes through the shower cooler system.In this case, water is ejected into by jet nozzles in the air-flow that comes out from the first centrifugal stage compressor.By making in this way, just fall by very little pressure and can obtain higher rate of heat exchange, because gas contacts tightly with water.Therefore in intercooling stage, do not have plank and pipe, from this part of this process, removed any thermal resistance.It has also reduced expense, complexity and size.

The main meaning of this layout is that the screw rod level of back can be accepted the gas/water mixture, and this mixture can cause further improving compression efficiency.By adopting this method, a part of water can join in the screw rod effectively in the ingress.Although in the screw compressor that water overflows, add whole water by this way, in a preferred embodiment of the invention, this part water is approximately half, in the compression process in screw rod, sprays remaining water on some neutral positions.This is preferred because it has such effect: needs it the time rather than institute a position sometimes add liquid.

By the water droplet size size of carefully regulating water velocity and injection, water is accepted compression heat.

In a preferred embodiment, the screw compression level of proposition of the present invention and conventional fixed speed water lubrication (but the variable velocity second level also is acceptable) is used the high speed centrifugation level of variable velocity in combination.

The screw compressor of water lubrication needs water filtration and purified treatment to guarantee that sediments and particulate can not be formed in the machine.Improve or reduce the closed circuit water level by the humidity size that changes in the pressurized gas.Therefore, most traditional compressor has adds and the discharge system, and this system can regulate the water in the machine continuously.Therefore, spraying intercooling stage is consistent with this needs, and this system extends to this additional features of adjusting easily.

In the screw rod level of water lubrication, have water, can not need aftercooler.Nominally the gas that comes out from the screw rod level is 50 ℃, simple centrifugal separaton and refrigeration drier guarantee that all water can utilize again, and the gas of being carried does not have pollutant and especially do not have oil.

Description of drawings

Now, by example, further describe the present invention with reference to accompanying drawing, this accompanying drawing schematically shows two stage compressor of the present invention.

Embodiment

In unique accompanying drawing, some conduits that gas flows along them are represented with two-wire, and are shown to single line with label 24 pipes represented, transporting water.

The gas that compresses enters into electrically driven (operated) centrifugal compressor 10 at 22 places.In case be subjected to the compression of centrifugal compressor 10, hot gas flows through water and sprays interstage cooler 12 so.

Water sprays interstage cooler 12 and is actually a jar, and this jar slows down gas.Simultaneously, water is ejected in the jar with high pressure by nozzle or sparger 20.These make water smoke change into mist, and this mist makes the motion gas cooling that slows down now, thus wherein motion gas slow down the feedwater come from gas, to absorb heat with more time.The droplet size size of regulating the water velocity in the interstage cooler and spraying bundle is accepted by cooling water with the compression heat of guaranteeing gas.This cooling means can avoid using heat exchanger, and the volume of these heat exchangers is big, price is expensive, produce that pressure falls and owing to use foil to be easy to damage, because the deposition of the accumulation of fouling and other chemicals and obstruction easily.

In the treatment phase of the next one, the cooler pressurized gas enter the inlet of the screw compressor of water lubrication, and there, it is further compressed.Screw compressor such as this have two counterrotatings, intermeshing screw rod forms.When they rotate, be collected in gas between them and be forced to along the length of screw rod downwards, be pushed far more along screw rod gas, compression is just big more so.If like that the compressor 14 of water lubrication has the water spraying as shown in the figure, so when the compression process heated air, at the water of injection from water source 18 under pressure on some neutral positions of screw rod through overregulating, thus cooled gas.If the screw compressor that water is overflowed, all water enter together along with handling gas so, and do not need to lead to from water source 18 pipe the compressor 14.

Use in many equipment of this compressor at needs, importantly, water should not have to promote impurity such as inorganic matter and any particle of bacterial growth.

In the shown embodiment of the invention, directly remain in the closed circuit with the interactional water of air-flow, this closed circuit forms by being positioned at before the screw compressor 14 with afterwards water pipe 24 and airline and separator 16.In particular, when discharging from screw compressor 14, gas passes through separator 16, thereby isolates most water to carry out recirculation from gas.The water that cools and isolates by heat exchanger 26, thereby take out the heat that during centre cooling and compression process, from gas, is absorbed there from it, and be recycled in the interstage cooler 12 and before being recycled to screw compressor 14 when needed at it, it is by water source 18.Can realize that by traditional outside water or coolant circulating system the cooling of the water in this closed circuit, these circulatory systems comprise air-supply cooler, cooling tower or even river by heat exchanger 26.

Shown system supplies to water the operation element of interstage cooler jet nozzles 20 and screw compressor 14 from identical water source 18.Be used for driving water and make it to spray pressure that interstage cooler nozzle 20 comes out to enter into screw compressor providing by the gas pressure in screw compressor 14 outlet ports from water.

Claims

1. multistage compressor, this compressor comprises:

The electronic rotation dynamic compressors of the variable velocity first order (10);

The screw compressor second level (14) of water lubrication, it is in series with rotation dynamic compressors level at the downstream part of rotation dynamic compressors level; And

Interstage cooler (12), it is arranged between this two-stage, thereby has reduced the temperature of the gas that enters into the screw compressor level,

It is characterized in that,

Interstage cooler (12) is that water sprays interstage cooler, and it and the water source (18) of screw compressor level (14) share common of water lubrication reach

Discharge gas and be fed directly in the screw rod level (14) from the water of interstage cooler (12).

2. multistage compressor as claimed in claim 1 is characterized in that, the first order (10) comprises the high-speed centrifugal compressor.

3. as claim 1 or 2 described multistage compressors, it is characterized in that the second level (14) are screw compressors fixed speed, that water sprays.

4. as claim 1 or 2 described multistage compressors, it is characterized in that the second level (14) are the screw compressors that the water of variable velocity sprays.

5. multistage compressor as claimed in claim 1 or 2, it also comprises separator (16), thereby removes whole basically water from the gas of being discharged by second compressor stage.

6. multistage compressor as claimed in claim 5 is characterized in that, shared water source (18) obtain water from separator (16), and comprise controlling device.

7. multistage compressor as claimed in claim 6 is characterized in that, heat exchanger (26) is provided with to cool off from separator (16) and turns back to water the shared water source (18).

8. multistage compressor as claimed in claim 1 or 2 is characterized in that, regulates the water velocity and the water droplet size size of the injection in the interstage cooler (12), thereby guarantees that cooling water accepts the gas compression heat.