A method and a device for producing an air product based on cryogenic rectification; after being cooled by a main heat exchanger, raw material air and nitrogen compressed by means of a compressor are sent to a rectification system for low temperature separation. In the rectification system, products such as oxygen and nitrogen are obtained by means of low temperature separation, and oxygen-enriched liquid air is obtained at or near the bottom of a rectification tower. The oxygen-enriched liquid air or liquid-state air in the rectification system is sent out after being raised to a target pressure by means of a low temperature liquid air pump; air products of various pressures can be produced by means of selecting low temperature liquid air pumps with different lifts or by connecting in series different amounts of low temperature liquid air pumps. The present method can avoid the need to arrange additional air compressors, entirely changing the method for producing medium and high pressure air products in a nitrogen circulation process, and importantly can reduce production costs significantly whilst having greater flexibility. In addition, the present method can increase the oxygen extraction rate of an apparatus, thereby improving the energy efficiency level.

An air separation process having a first booster air compressor comprising a first outlet stream and a second booster air compressor comprising a second outlet stream. Wherein the first booster air compressor and the second booster air compressor are in parallel, and the second booster air compressor is driven by a nitrogen turboexpander. The first outlet stream and/or the second outlet stream may be at least partially condensed by heat exchange with a vaporizing low pressure oxygen stream, and the low-pressure gaseous oxygen pressure is in the range of 1.1 bara to 3 bara.

The invention relates to a process for cryogenic fractionation of air using an air fractionation plant comprising a rectification column system comprising a high-pressure column operated at a pressure level of 9 to 14.5 bar, a low-pressure column operated at a pressure level of 2 to 5 bar, and an argon column. It is envisaged that a recirculating stream is formed using the second tops gas or a portion thereof, which is heated, compressed, cooled again, and after partial or complete liquefaction or in the unliquefied state is introduced partially or completely, or in fractions, into the first rectification column and/or into the second rectification column. The present invention also relates to a corresponding system.

A method for obtaining one or more air products by means of an air separation unit comprising a first booster, a second booster, a first decompression machine, and a rectification column system which has a high-pressure column operated at a first pressure level and a low-pressure column operated at a second pressure level below the first pressure level. All of the air supplied to the rectification column system is first compressed to a third pressure level, which lies at least 3 bar above the first pressure level, as a feed air quantity. A first fraction of the feed air quantity is supplied to a first booster at the third pressure level and at a temperature level of −140 to −70 ° C. and is compressed to a fourth pressure level using the first booster.

A method and apparatus for producing a high-pressure gas from an air separation unit is provided, in which the method includes the steps of introducing a cold air feed into a distillation column system under conditions effective for separating the cold air feed into a first air gas and a second air gas; withdrawing the first and second air gases from the distillation column system and warming said first and second air gases in a main heat exchanger, wherein the first air gas is withdrawn from the distillation column system at a medium pressure; splitting the first air gas into a first fraction and a second fraction; expanding the first fraction in a turbine; and compressing the second fraction in a booster to a pressure that is higher than the medium pressure, wherein the booster is powered by the turbine

A polymer handling method for a polycrystalline silicon manufacturing device, wherein the polymer byproducts are treated in a manner that the silicon polymers are hydrolyzed. The method creates a heated treatment gas with a moisture content that both treats the polymer to a depth of about 0.25 mm to prohibit formation of the friction and shock sensitive layer near the polymer surface and keeps the hydrolyzed polymer humidified. Furthermore the polymer handling method includes inactivation of the polymer, removal of the polymer of the system and disposal of the polymer after removal.

A method and a device for producing an air product based on cryogenic rectification; after being cooled by a main heat exchanger, raw material air and nitrogen compressed by means of a compressor are sent to a rectification system for low temperature separation. In the rectification system, products such as oxygen and nitrogen are obtained by means of low temperature separation, and oxygen-enriched liquid air is obtained at or near the bottom of a rectification tower. The oxygen-enriched liquid air or liquid-state air in the rectification system is sent out after being raised to a target pressure by means of a low temperature liquid air pump; air products of various pressures can be produced by means of selecting low temperature liquid air pumps with different lifts or by connecting in series different amounts of low temperature liquid air pumps. The present method can avoid the need to arrange additional air compressors, entirely changing the method for producing medium and high pressure air products in a nitrogen circulation process, and importantly can reduce production costs significantly whilst having greater flexibility. In addition, the present method can increase the oxygen extraction rate of an apparatus, thereby improving the energy efficiency level.

A method for separating air by cryogenic distillation, wherein air is compressed in a first compressor, cooled in a heat exchanger and then separated in a system of columns, liquid oxygen is vaporized in the heat exchanger countercurrent to a flow of pressurized gas which pseudo-condenses, a flow of gas which is air or a gas delivered from the system of columns is expanded in a cryogenic expansion turbine having a single wheel, the turbine having an inlet temperature lower than 100 C., a gas which is air or a gas delivered from the system of columns is compressed in a first booster compressor having a single wheel, with an inlet temperature higher than 50 C., a gas which is air or a gas delivered from the system of columns.

A method and apparatus for producing compressed nitrogen and liquid nitrogen. A separation system has a high-pressure column, a low-pressure column with a top condenser and a main condenser. Air is compressed in an air compressor, purified, cooled in a heat exchanger and introduced into the high-pressure column. A first part of the gaseous top nitrogen from the low-pressure column becomes compressed nitrogen product. A second part of the gaseous top nitrogen is condensed in the condensing space of the top condenser and vapor is drawn off as a residual gas stream. The vapor is expanded in a first expansion machine. A second compressed nitrogen stream from the top of the high-pressure column is expanded in a second expansion machine and then drawn off as compressed nitrogen product. A part of the nitrogen condensed in the top condenser is drawn off as liquid nitrogen product.

A polymer handling method for a polycrystalline silicon manufacturing device, wherein the polymer byproducts are treated in a manner that the silicon polymers are hydrolyzed. The method creates a heated treatment gas with a moisture content that both treats the polymer to a depth of about 0.25 mm to prohibit formation of the friction and shock sensitive layer near the polymer surface and keeps the hydrolyzed polymer humidified. Furthermore the polymer handling method includes inactivation of the polymer, removal of the polymer of the system and disposal of the polymer after removal.