Gasifier is a device in the form of a sealed metal tank (cryocylinder). The more accurate name for this unit is Cold Cryogenic Gasifier (CCG), since gas liquefaction is achieved at ultra-low temperatures and vaporization is achieved at ambient temperature without additional heating.
Gasifier’s purpose is storage and liquid cryoproducts (oxygen, nitrogen, argon, methane, etc.) gasification with their further conversion from liquid to gaseous phase. Gasifiers are used by industrial enterprises, construction organizations, medical institutions. Gasification makes it possible to significantly facilitate gas supply to the object, increase business efficiency.
Application: medicine, metallurgy, metal recycling, food industry, thermal power, mechanical engineering, etc.
It is one of the key devices for enterprise gasification, which is much more convenient than high-pressure cylinders. On average, one cubic meter of liquid gas is equal to 100-140 cylinders of compressed gas, which helps to save money over the long-term period: installing a gasifier at a facility using gas regularly pays for itself quickly.
Gasifier types
The main division is made according to the mobility of the design:
- Stationary gasifiers are large units capable of producing up to 2000 cubic meters of gaseous product per hour. Stationary cryogenic gasifiers should be located at a distance of 10 meters or more from buildings, on a specially constructed concrete foundation. They can be combined in modules to increase their volume.
- Mobile gasifiers are designed also for transportation, capable of transporting up to 3 m3 of product volume.
Cryogenic gasifiers design and operation principle
The cryogenic gasifier can be designed as a single tank or as a group of vertical or horizontal tanks. Its main components are:
- A cryovessel (one or more) for cryoproduct storage, which consists of an inner vessel and an outer shell;
- Production atmospheric evaporator and pressure lift evaporator;
- Various valves (regulating, shut-off, safety valves);
- Instrumentation and Control (I&C).
Austenitic stainless steel (with increased content of chromium and nickel) with high cold fracture resistance is used for gasifier inner cylinder manufacturing. The gasifier outer casing material is usually carbon steel. To minimize stored cryogenic liquid natural evaporation losses, air is evacuated from the inter-wall space, creating a deep vacuum.
A cavity is filled either with parallel metallized screens with high reflectivity (screen-vacuum insulation) or with expanded perlite sand (perlite-vacuum insulation). The first option is more effective, but it is almost not used for tanks with a capacity (volume) of more than 500 liters due to complex winding technology of heat-reflecting layers, which requires vessel rotation. Therefore, for stationary gasifiers with a capacity of more than 1000 liters, the second scheme is considered optimal.
Another cryogenic insulation method is vacuumless, which involves the use of hydrophobic fillers such as foamed rubber and cryogel based on foil-coated glass fiber. The latter is more versatile, as the use of rubber limits the lower limit of operating temperature (-200 °С). This progressive insulation technology is becoming more and more widespread, as it ensures gasifiers and cryogenic storages of any modification long and reliable operation.
System’s main objective is to store gases efficiently for a long time period and to transfer them to the consumer. The gas is supplied to the line through its displacement by the internal tank overpressure, directly the pressure is raised through liquid evaporation via heat exchange with air. Vaporization takes place without connecting a heat source, which is why gasifiers are called “cold”.
A standard system consisting of a pressure lift coil, its regulator, economizer and valve is fully automated, it does not require manual on/off switching.
The gasifier’s outer casing is made of durable and damage-resistant carbon steel. All systems and materials are designed to work with cryogenic equipment, which is known to have a detrimental effect on many types of steel. This results in slower wear and tear and longer service life of units.
In compliance with industry requirements and in order to meet customers’ needs, we provide cryogenic vessels of various specifications.
We deliver equipment completely pre-assembled and ready to use with all necessary authorization documents. To select a cryogenic vessel with evaporator and to specify its price, please contact us by phone +7 (495) 150-44-22. You can also send us a request and technical specification by email info@onhs.ru.
