Lines of activities >  Integrated design >  Helium recovery

Helium recovery

Helium belongs to rare elements and has unique properties. It is characterized by chemical inertness and low ability of participation in nuclear reactions, higher thermal conductivity and lower electric conductivity as compared to other gases, low solubility, light weight, low(near the absolute zero) boiling temperature, non-toxicity, the absence of colour and odour, non-flammability in gaseous state and a number of other valuable properties.

Such combination of properties predetermines ever-growing use of helium in various areas of science and engineering: aviation and astronautics, ship-building, chemical, metallurgical and welding facilities, nuclear engineering, medicine, chromatography, cryogenic engineering, etc.

Almost all the helium produced in the world is consumed by the countries included in the top ten of developed countries. The first place in helium consumption in the world market is occupied by the USA, the second by the Western Europe countries, the third by Japan.

Major raw materials for helium production are natural and associated petroleum gases.

Helium production costs are almost inversely proportional to helium concentration in the gas being processed. Helium cost depends also on the complexity of gas processing (additional recovery of ethane, technical propane-butane, LPG, natural gasoline, etc.), the plant capacity, quantity of initial contaminating impurities in gas, plant location, local conditions of gas consumption and transportation.

Estimated energy costs of helium recovery from gases containing 0.02, 0.05, 0.35% of helium are 250, 100 and 18 kWt h/cub.m, respectively.

In today's Russia, helium is produced from natural gas with low helium content (up to 0.055% by volume) at the helium plant in Orenburg.

At the helium plant there are five operating units, each with the capacity of 3.0 billion cub.nm/h in terms of feed gas. Along with helium, ethane and LPG are recovered from gas.

Our company developed and implemented the process and major process equipment used at the helium plant in 1970s-1980s.

Currently, the issues of integrated gas processing with recovery of helium and valuable hydrocarbon products are in the area of activities of LENNIIHIMMASH.

Helium recovery from natural gas on industrial scale is performed by the condensation-stripping method. Cold sources for cooling and condensation process are: adiabatic process of gas expansion in a turbo-expansion unit; throttle effect using the potential of gas supplied for processing, and closed-circuit cooling cycles (propane cycle, nitrogen cycle, hydrocarbon-nitrogen mixture cycle).

Use of one or several cold sources depends on parameters of source gas supplied for processing, on requirements imposed on quality of helium concentrate that can be conveyed to an underground storage facility or for further processing in order to produce pure helium.

Hydrocarbon condensate produced by cooling is subjected to rectification for production of valuable market products: ethane fraction, LPG, technical propane-butane, stable natural gasoline or individual liquid components, depending on the demand.

The process and main process equipment for integrated gas processing have been sufficiently optimised by LENNIIHIMMASH. Equipment for a plant having a capacity of up to 3.5 billion cub.nm/year in terms of source natural gas can be manufactured in Russia (except for turbo-expansion unit, some types of compressor and pump equipment and some portion of cold quick-acting valves).

With economy recovery and further development of science and engineering, we should expect the advent of fundamentally new, efficient technical devices using special properties of helium, which must lead to a significant increase in demand for helium in the country. In addition, there is a prospective of export helium supplies to markets of Japan, China, countries of Southeast Asia and Western Europe.

Therefore, an urgent issue is implementation of integrated processing of natural gases from large fields of Eastern Siberia that have high helium content (from 0.15 to 0.6 %).

High helium content of gas and the use of integrated gas processing technology will allow a significant reduction of helium cost as compared to the cost of helium produced at Orenburg helium plant; the cost will be comparable with that of helium produced in the USA. Further, realization of excess products in the international market, including payments of those products to investors, may solve the problems of gas field development in Eastern Siberia.

In foreign countries, it is preferred to transport and sell helium in liquid state. Therefore, it is necessary to organize in Russia a system for liquid helium factory storage, transportation and distribution corresponding to up-to-date technologies and services.

In conditions of lack of roads in regions of Eastern Siberia and Republic of Sakha (Yakutia), it is reasonable to transport helium to the user in liquid state, in large-size tank cars by railway to ports and then by sea. Deliveries to China can be carried out by direct railway communication. Small lots can be transported by air.