Surgil ESIA Report - Volume III - EKN

“O’ZLITINEFTGAZ” PC
PFS “Surgil field complex costruction with valuable
components retrieval”
According to results of hydraulic calculation, if the pipe diameter is 273х9mm and
the collector maximum length is 3.8km, so the pressure loss makes 0.56MPa. Gas pressure
and temperature at input in GS will make 7.24MPa and 39 0 С relatively.
Gas collector
Pressure – 10.78MPa
Diameter – 273mm
Length – 3.8km (each)
At the given stage the anthropogenic impact will be expressed in use of the lands
under construction of GGS and gas-field gathering mains, and also in emissions of gas
combustion products in atmosphere on torches during purging of collectors sites (periodic
and short-term).
2.6 Complex Gas Treatment Unit (CGTU)
For gas transportation through the main gas pipelines there are necessary careful
clearing and dewatering of gas from solid impurities, aggressive components and moisture
as they promote quick deterioration of the expensive equipment and cause disturbances in
the conditions of normal operation.
It is offered to carry out gas treatment on CGTU located on the field area, by method
of low-temperature separations (LTS) with gas cooling at the expense of its expansion in
turbo-expander.
Treatment of the hydrocarbonic condensate allocated during gas separation on the
LTS plant, is offered to make by open system of condensate gathering. Condensate is
exposed to step aeration (separation, degassing) on the condensate separation and aeration
plant. Gas condensate completely disappears under atmospheric pressure, and represents a
stable condensate by saturated vapors pressure.
Prevention of hydrate formation in the LTS plants is carried out by input of hydrate
inhibitor into gas stream through sprayer directed towards gas flow for the best inhibitor
dispersion in the gas stream and maintenance of its contact with water. It is offered to use
diethyleneglycol (DEG) as anti-hydrate inhibitor on the CGTU.
Production which is produced on the CGTU will be nonsulfurous dry combustible
natural gas meeting on quality requirements of state standard Oz’DSt 948:1999 and stable
gas condensate, meeting requirements of standard TSt 39.0-02:2004.
CGTU productivity is defined proceeding from conditions of gas extraction from the
field by years (including the term of attainment of constant extraction and the period of
constant extraction) taking into account necessary requirements for reservation of
equipment capacity.
Design productivity of CGTU makes 3.0·10 9 m 3 per year. Productivity of one
technological line of LTS for gas is 3.0·10 6 m 3 /day. Plant inlet pressure is 7.24MPa,
Volume 2. Part 1. EIS Project for Surgil field construction
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