"Installation of offshore compressor stations in the field is the only long-term option to control gas pressure reduction," Mohammad Meshkinfam said, ILNA reported.
Contrary to popular belief, the field will not be able to produce 630 million cubic meters of gas per day (the current output) forever and this clean resource should be used as prudently as possible, he stressed.
Referring to past short-term policy to postpone pressure reduction, he said his company has started to acidize offshore wells and this will delay the process maximum by two years, according to Financial Tribune.
"By 2021, the pressure is expected to decline by 28 mcm per year unless special platforms and compressors are installed. To do so in all the phases, each needs approximately $1 billion.”
South Pars accounts for 80% of Iran’s gas need and decline in SP output could create problems for consumers.
Sizeable Risk
According to the POGS chief, the new installations are 10 times heavier and domestic firms have undertaken the complex tasks. “However, relying solely on them could carry sizeable risks because they have never performed such a task.”
"Installed gas platforms weigh almost 2,500 tons and are designed to produce 28 mcm of gas per day. However, the new platforms which will hold the compressors are estimated to weigh at least 20,000 tons," Meshkinfam said.
The platforms, which are necessary to maintain gas pressure, will be unrivaled in the region and there are a few of its kind in the world. One was constructed in Australia with the help of French energy company Total.
Total SA was to provide the National Iranian Oil Company with the know-how to build the structures but shied away after US President Donald Trump last year walked away from the historic 2015 Iran nuclear deal and re-imposed sanctions on the oil and other key industries.
Referring to domestic potential and capability, the senior official said firms like Petropars, a subsidiary of NIOC, are willing and able to undertake offshore drilling operations and transfer gas to onshore refineries, but are deprived of technology to manufacture heavy platforms and compressors.
“Pressure reduction will anyway take place. However, other gas fields in the Persian Gulf including Kish, Ferdowsi and Golshan might help compensate for the output reduction [but not for long]."
Reservoir pressure in SP was higher when the first contract for development of the giant field was signed years ago, he recalled.
“Qatar's excessive gas extraction from the field has reduced the pressure to a great extent and further lowering of pressure will affect production from the operating platforms in the near future.”
Substantial Improvement
The field's production (30 mcm/d) has risen by 121% compared to 2013 when output was 285 mcm.
"There were 11 platforms in SP in 2013, but the number has reached 32, up 190%," he said, adding that the number of onshore refining units is up 150%, increasing from 20 in 2013 to 50 in 2019.
POGC, a subsidiary of NIOC, oversees the development of the major gas field in its entirety.
Iran has close to 34 trillion cubic meters of natural gas reserves -- about 18% of the total global natural gas reserves.
South Pars is the world’s largest gas field, shared between Iran and Qatar, covering an area of 3,700 square kilometers of Iran’s territorial waters in the Persian Gulf. It adjoins Qatar’s North Field that measures 6,000 square kilometers.