ETHANE PRODUCTION TECHNOLOGY

A set of patented process solutions is a feature of the proposed technology:

The licensed process solutions offered by PEGAZ are based on the most efficient and up-to-date process – low-temperature gas rectification using a refrigerant circulation system. A feature of the process is a higher degree of of C2+ components extraction along with high specific energy efficiency. Due to stabilization of the feed gas temperature, automatic process control and equipment maintenance are simplified, and the unit also becomes more resilient to possible changes in the composition of feed gas and seasonal temperature fluctuations.

A set of patented process solutions is a feature of the proposed technology:
1. The use of the refrigerant circulation system and a separator gas refluxer, which makes it possible to reduce capital costs by avoiding turbo-expander units, as well as reduce energy consumption by excluding the circulation of dry stripped gas recycle streams produced within the unit. The refrigerant circulation system consists of compressors, ACUs, separators and heat exchangers. Design of this system is simple in terms of process, and at the same time is energy efficient, allowing to avoid using complex foreign-made equipment, which is an advantage in conditions of foreign licensors leaving.
2. The use of liquid low-temperature refrigerant allows to reduce the load of the column in terms of gas phase, which leads to decrease in the diameter of the reinforcing (concentration) part of the demethanizer column. And, as a result, there is a reduction in metal consumption and capital costs.
3. The advantage of a refluxer use is that reflux gas is enriched with methane and, at a reduced temperature, is supplied to the refrigerant circulation system as a refrigerant, at the same time C2+ hydrocarbons extraction is increased (design value of 96.5% by weight.) as well as the process specific energy efficiency is increased.
4. The technology uses cold recovery from demethanizer side streams for cooling of dry treated natural gas. This solution makes it possible to avoid the use of external sources of cold, and also allows more efficient use of internal streams cold, thereby achieving greater energy efficiency and reducing the load on the reboiler of the demethanizer bottom.
5. There is no need to use multi-flow heat exchangers, which simplifies the design of the unit and stabilizes the the process behaviour.
6. The process is adapted to the use of equipment produced in Russia and is "license-clean".
7. The process has a possibility of further unit development in accordance with the planned business process, particularly:

• LNG production for the local market or its export;
• processing of NGL at gas fractionator – additional sales products and/or products of their processing.

 

Further monetization of dry stripping gas can be achieved by construction of a methanol production plant and processing of methanol into products with high added value:

 

• olefins and dienes (ethylene, propylene, butadiene, isoprene) and polymers on their basis,
• aromatic hydrocarbons (it is feasible to co-process methanol in a mixture with propane-butane fraction),
• formaldehyde and its derivatives (carbamide-formaldehyde and phenol-formaldehyde, carbamide, melamine and other synthetic resins, as well as polyformaldehyde),
• oxo-synthesis products: acetic, oil and other aldehydes,
• acrolein, acetic anhydride, isopropyl, butyl, as well as higher fatty alcohols,
• glycols, simple and compound ethers, etc.