Initiative to benefit 30 billion dong at PV GAS

In 2019, Vietnam Oil and Gas Group (PVN) has rated Special (type A) for the initiative “Conversion of high pressure compressors GTC-A / B DGCP rigs” with the value of benefiting more than 30 billion dong for enterprises

The initiative was implemented by the author Nguyen Tan Hoang and his co-authors: Trieu Quoc Tuan, Nguyen Minh Tuan, Nguyen Phuong Cao, Bui Tan Hung, Pham Thanh Tu and Do Ngoc Tan who are leaders, engineers of two enterprises directly under Vietnam Gas Corporation – JSC (PV GAS): Southeast Gas Transport Company (KĐN) and Gas Services Company.

Rong – Doi Moi Compressor construction (DGCP) is a project invested by PV GAS and put into operation from November 2010. KĐN is assigned by PV GAS to manage, supervise the operation and the Gas Works Exploitation Enterprise – Vietsovpetro is directly hired by PV GAS to operate the project.

The construction is designed and built including two high-pressure compressor assemblies with a compressing capacity of 900,000 m3 of gas per day to collect all the associated gas of the Rong-Doi Moi mine area to compress again into the general gaslift system of Vietsovpetro. The additional gaslift from DGCP contributes to a share of gaslift demand from the Central compressor (CCP), indirectly increasing the amount of gas supplied ashore to meet part of the Southeast region’s gas market demand.

Over the course of nearly 10 years of operation, the staff and engineers working here have studied and applied many technical solutions and scientific initiatives to ensure the stable, reliable and effective operation of equipment systems; contributing to the ability to collect associated gas and increase the amount of gaslift supplied to the Dragon field from the DGCP platform.

In the second half of 2015, two high-pressure compressors (GTC-A / B) on Dragon gas compressors decreased their compressive capacity very quickly after more than 1 year of overhaul, losing about 20% of the air flow compared to the previous time. The decline in capacity of the two compressors not only affect PV GAS ‘increase in ashore production but also affects Vietsovpetro’s oil production.

Concerned with this situation, the cadres and engineers of KĐN were determined to quickly find a solution to overcome.

Under the close and timely guidance from the leadership and internal solidarity, the author team collaborated with related businesses such as Gas Services Company, Gas Works Exploitation Enterprise – Vietsovpetro, Solar (the manufacturer of these 2 compressors) to find the best solution possible.

After a long period of research, review, evaluation and elimination of causes, the authors have found specific causes stemming from two main factors:

The first is the dirty input air, which contains lots of paraffin, which is drawn into the compressor, which contaminates the wings of LP, HP Comp and the lighter density of gas compared to the design makes the compression more difficult and requires more energy , so turbine engines must operate at full capacity.

The second is due to internal problems of equipment because the distribution of compression ratio between LP Comp and HP Comp levels is not really suitable. These errors do not appear immediately after the overhaul of the machine so engineers have a hard time finding the cause.

From that analysis, the authors and related businesses have come up with a solution: Must control the source of input gas. Implementing the plan of converting high-pressure compressors to suit the current nature of the gas source to ensure the compressive capacity of the machine and the compressor’s operating time until the next overhaul cycle.

Representative of the author group, Mr. Nguyen Tan Hoang shared: GTC-A / B compressor is a 2-stage centrifugal compressor, each level is composed of consecutive wings, the air flow pressure through the compressor will is gradually raised through the wings. The shape, structure and number of wing layers depend on the compressor series, the outlet inlet pressure, the nature of the fluid flow … The specific case with the GTC-A / B compressor on the DGCP platform is The nature of the compressed fluid (gas density) has changed compared to the design, so it is required to perform restage – reconfigure the compressor by changing the wings of the shape, structure, quantity to in accordance with current operating parameters.

When the solution is put into practice on the gas collection system in Rong – Doi Moi field, the machine operates more safely and stably; level 1 outlet temperature (LP) decreases by about 10 ° C (175 ° C to 165 ° C); gas output through the machine increased from 3-7%, the total output is stable in the range of 1,030-1,080 ksm3 / day and night. This achievement is clearly shown in the specific figures with the increase in gas calculated to have benefited PV GAS as well as PVN over 30 billion dong.

Sharing about solutions, the authors believe that innovation and improvement are very in need of intellectual mobilization of the collective to quickly put into practice. In the author group, there are people with the title of director, deputy director, but when problems or problems arise, the leader does not mind difficulties, all forming a solid link  for the purpose of accomplishing a common task. It can be said that, “the hard-to-be-wise”, through practical labor, the initiatives launched not only bring about high economic benefits but also promote the emulation movement to promote innovation and technical improvement in the business.

Monitoring the operation of the rig in gas transmission works is a relatively complex task, new technology is constantly updated, so it is constantly learning and updating knowledge to keep pace with technological changes bridge needed. As excellent employees of the Oil and Gas industry, despite many high achievements in research, producing many widely applied initiatives, the authors have never been satisfied with the achievements. In them, there is always a passion for work, the desire for dedication and the spirit of self-study, raising the qualifications to meet job requirements, applying science and technology into the management and production process.

Productivity and Quality Office