Industrial Gases

IMPROVEMENT OF AMMONIA, CARBON DIOXIDE AND UREA PRODUCTION

2017-11-28T11:13:32+02:00

On June 13–16, 2017 in Odessa there was held the VII-th International Seminar by Eastern European Association of Industrial Gases Manufacturers «SIGMA» and the Institute of Low-Temperature Energy Technologies Ltd. The issues discussed at the seminar related to the current problem of improving the production of ammonia, carbon dioxide and urea. The topics of the seminar are of interest to manufacturers and consumers of these highly liquid products, as well as to those who develop and manufacture the necessary chemical and technological equipment. The reports presented the results of modernization of ammonia and urea units and new effective technologies for large-tonnage production of ammonia and urea. The most promising for the production of ammonia is Megammonia technology, developed by the company «Сasale» together with the company «Lurgi». It is shown that using a new air cooling system fed to the granulation tower, it is possible to increase its carbamide productivity by 40 thousand tons.

PROVISION OF EFFECTIVE AND SAFE OPERATION OF CENTRIFUGAL COMPRESSORS with TURBINE-DRIVEN OF AMMONIA PRODUCTION

2017-11-28T11:15:23+02:00

In ammonia production plants, turbine-driven centrifugal compressors are one of the most important non-reserved machines. In this regard, great attention is paid to improving their technical and operational performance. An overview of measures on the machinery maintenance improvement in the ammonia production shop of Odessa Port Plant is presented. The results of studies of the thermal state of centrifugal compressors, their vibration tests and modernization carried out by specialists are presented. All this allowed creating and using an efficiently operating system, including planned preventive maintenance of compressor-turbine units, their maintenance in actual condition and proactive maintenance.

IMPROVEMENT OF CRYOVESSELS THERMAL SHIELDING

2017-11-28T11:14:44+02:00

The technique is developed for the first time providing optimal pressure in a vessel thermal shielding, at which the shielding effective thermal conductivity does not further depend on this parameter. To achieve the result, an accelerated process is proposed for thermal vacuum degassing of isolation cavities of cryovessels in electrical oven at temperature 390 K during 160–180 hours until experimentally determined value of optimal gassing. The development of the method for building cryovessels with optimal gas pressure in the thermal shielding is an important stage for their improvement and also promotes further studies for getting better characteristics.

COOLING SYSTEMS IN APPARATUSES FOR CONDENSATION CLEANING OF Nе-Hе MIXTURE AT THE LEVEL OF TEMPERATURES 68 ... 78 K

2017-11-28T11:13:48+02:00

Rare gases are highly needed products obtained using high technology. In this regard, much attention is paid to improving the equipment used in these technologies. Methods for cooling phase separators used for condensation enrichment of a neon-helium mixture are considered. The most common option involves an open-loop refrigeration cycle based on liquid nitrogen. However, the boiling point of nitrogen at atmospheric pressure does not ensure achieving the required concentrations of neon and helium. Alternative methods for cooling the separators to lower the temperature to the value of Т 68 are proposed. As a result, additional enrichment of the mixture with the target products at the output from the phase separators is obtained.

IMPROVEMENT OF PERFORMANCE AND EFFICIENCY OF CARBAMIDE UNITS AT ODESSA PORT PLANT

2017-11-28T11:14:59+02:00

Carbamide (urea) is a highly liquid product representing the most concentrated nitrogen fertilizer. It is produced at large-scale chemical industry enterprises. A well-known manufacturer of granulated urea is Odessa Port Plant which has been operating two units on urea production since 1984 and 1985. They use the technology of «Stamicarbon» stripping process. Design daily capacity of each unit was 1000 tons. The plant specialists constantly focused on ensuring their safety, increasing productivity and efficiency. Reconstruction and modernization of the units began in 2000, and it was conducted in several stages. At each stage, the task was set to achieve a certain level of productivity of the units with the simultaneous creation of a platform for further improvement of carbamide production. Many implementations were carried out with the participation of the plant specialists. Their novelty and prospects were protected by patents of Ukraine. As a result, it was possible to significantly increase the daily capacity of the units: up to 1350 tons (unit No. 1) and 1500 tons (unit No. 2). In addition, there were reduced consumption factors for NH3 (from 0,58 to 0,57) and steam (from 0,80 to 0,72) per ton of carbamide. The experience accumulated by experts is particularly valuable because in each unit different approaches to the organization of work were applied, which were based on the use of equipment that was in operation on one of the units, while the other unit was being reconstructed.

APPLICATION OF STIRLING OPEN CYCLE TO OBTAIN ENERGY IN THE GASIFICATION OF CRYOGENIC LIQUIDS

2017-11-28T11:14:33+02:00

We carried out a comparative analysis of various intermediary energy carriers which can be used in vehicles instead of hydrocarbon fuel. It is shown that if liquid nitrogen or air is used for this purpose, scarce components, for example, lithium-ion batteries or fuel hydrogen elements will not be required, which will substantially reduce the necessary capital investments. The review of known designs of automobiles working on liquid nitrogen or air has been carried out. It is noted that low efficiency of using the exergy of the cryogenic liquid in these designs has led to discrediting the very idea of the cryomobile. In the proposed design of the Stirling engine operating on an open cycle it is possible to use 57 % of the exergy of liquid nitrogen. A technique for calculating such an engine is described and the results obtained are presented. It is shown that 200 liters of liquid nitrogen is enough for 180 km of the cryomobile mileage at the speed of 55 km / h, while a full charge of a 300-kilogram battery of the electric vehicle Nissan Leaf is sufficient for 160 km.

CREATION OF A HIGH SPEED COMPRESSOR UNIT ON THE BASE OF 2M10A AND ITS TESTS IN THE REGIMEN OF RESONANCE SUPERCHANGE

2017-11-28T11:14:02+02:00

Creators of multi-stage reciprocating piston compressors, when working on the design of cryogenic air separation plants, tend to increase the speed of rotation. This approach allows reducing the mass and dimensions of compressors. At the same time, it is necessary to solve the complex problem of increasing their effectiveness. Peculiarities of the development of the opposite reciprocating compressor based on 2M10A with an increased speed of the crankshaft driven by a gas piston engine 280 GD are considered. The piston compressor uses effective self-operative strip valves of our own production. In the valves there are no moving parts in the form of springs or dampers. Attention was drawn to the static and cyclic strength of the crosshead assembly of the piston compressor. Tests of this unit have shown that it has almost 4-fold safety margin. The compressor has a block design and is highly balanced. Its tests in the regimen of resonance superchange have shown that the compressor's volumetric capacity can be further increased by 6 %.

JET APPARATUSES FOR FAST COOLING AND SLUSH STATE OF CRYOGENIC LIQUIDS PRODUCTION

2017-11-28T11:14:25+02:00

An analysis of cryogenic liquids’ cooling methods and systems showed jet coolers of liquids (JCL) prospective application. Cooling of the liquid is realized at the expense of its partial evaporation at the boiling flow outflow from the nozzle with the subsequent phases’ separation. It is possible to obtain flow slush state for nozzle outlet pressures lower than substance triple point. The working process of the device, theoretical and experimental investigation results are represented in article. JCL characteristics for oxygen, methane, hydrogen and nitrogen at the flow rate from 0,2 to 400 kg/s and installations on its base are also represented. The liquid cooling rate is more 400 K/s. The devices dimensions and mass 30...100 times lower than traditional superficial heat-exchangers. Up to 95% cryogenic liquids repeated use was provided at the cryogenic pumps tests. The slash nitrogen flow with the crystals’ dimensions less than 100 microns was obtained. It is possible to produce the slush hydrogen flow with the total pressure 0,06...0,.18 МPа and crystal phase’s dimensions less than 40 microns.