Senoro-Donggi-Matindok Natural Gas Development Project Comprehensive Report : Integrated Analysis from Upstream to Downstream

Introduction

From the summer of 2014 until the completion of construction and the handover of gas commissioning in 2015, I was permanently stationed at the Senoro CPP (Central Processing Plant) as the construction manager for PT TRIPATRA, the EPC contractor.

This project established a fully integrated value chain, spanning from upstream gas field development through midstream gas processing to downstream LNG, fertiliser (planned during my tenure), and power generation. It represents a strategic energy development initiative aimed at monetising Indonesia’s domestic economy. Based on my hands-on experience with the construction of supply facilities, from upstream to natural gas supply destinations, I will provide a comprehensive analysis of the technical and commercial structure.

Integrated Analysis from Upstream to Downstream

The Central Sulawesi region has rapidly developed as an essential natural gas production hub in Indonesia since 2015. This report provides a detailed analysis of the integrated value chain from upstream gas field development to midstream Central Processing Plants (CPP), and downstream LNG facilities, fertiliser plants, and power generation facilities, clarifying the commercial and technical structure.

Upstream Gas Field Development

Gas Fields Supplying Senoro CPP

1. Senoro Field

• Location: Senoro-Toili Block, Eastern Central Sulawesi
• Geology: Miocene carbonate reservoir (Mantawa and Minahaki carbonate sequence)
• Characteristics: First “giant gas field” in Central Sulawesi
• Operator: JOB Pertamina-Medco E&P Tomori Sulawesi
• Discovery year: 2007
• Reserves: 1.44 TCF (Phase 1)

2. Toili Field

• Location: Within Senoro-Toili Block
• Geology: Similar carbonate structure to the Senoro Field
• Characteristics: Integrated development with the Senoro Field
• Operator: JOB Pertamina-Medco E&P Tomori Sulawesi
• Development method: Integrated production with the Senoro Field

3. Tiaka Oil Field

• Location: Within Senoro-Toili Block
• Type: Oil field (associated gas production)
• Characteristics: Effective utilisation of associated gas from crude oil production
• Operator: JOB Pertamina-Medco E&P Tomori Sulawesi
• Products: Crude oil + associated gas

The gas field group supplying Senoro CPP holds a pivotal position as the pioneer of natural gas development in Central Sulawesi. Senoro Field, in particular, has been notable as the region’s largest “giant gas field” since its discovery in 2007, becoming the foundation for subsequent development strategies. The Miocene carbonate reservoir was formed through marine depositional processes, showing excellent porosity and permeability. The Mantawa and Minahaki carbonate sequence has particularly favourable reservoir characteristics, ensuring long-term production sustainability.

Gas Fields Supplying Donggi CPP

1. Donggi Field

• Location: Toili Barat District, Banggai Regency
• Geology: Miocene carbonate build-up reservoir
• Characteristics: High-quality carbonate reservoir
• Operator: PT Pertamina EP
• Discovery year: 2008
• Reserves: 0.70 TCF (part of Matindok Block)

2. Minahaki Field

• Location: Toili Barat District (adjacent to Donggi Field)
• Geology: Similar carbonate structure to Donggi Field
• Characteristics: Integrated development with Donggi Field
• Operator: PT Pertamina EP
• Development method: Integrated production with Donggi Field

Gas fields supplying Donggi CPP are concentrated within the Toili Barat District, achieving operational efficiency through geographical proximity. Donggi Field features Miocene carbonate build-up structures, exhibiting excellent reservoir characteristics despite its complex geological structure. Integrated development with the Minahaki Field enables efficient processing at a single CPP. These gas fields are characterised by a relatively high impurity content, requiring specialised processing technology at Donggi CPP.

Gas Fields Supplying Matindok CPP

1. Matindok Field

• Location: Batui District, Banggai Regency
• Geology: Miocene carbonate reservoir
• Characteristics: Major gas field bearing the regional name
• Operator: PT Pertamina EP
• Reserves: 0.70 TCF for the entire Matindok Block
• Development stage: Main production gas field

2. Maleoraja Field

• Location: Batui District (adjacent to Matindok Field)
• Geology: Similar structure to Matindok Field
• Characteristics: Supplementary supply source for Matindok Field
• Operator: PT Pertamina EP
• Development method: Integrated production with Matindok Field

3. Sukamaju Field

• Location: Batui District
• Geology: Regional common carbonate reservoir
• Characteristics: Supply expansion through additional development
• Operator: PT Pertamina EP
• Position: Additional supply source for maximising processing capacity

The gas field group supplying Matindok CPP forms the most complex supply system configuration. All three gas fields are concentrated within Batui District, achieving cost efficiency and operational simplification through geographical consolidation. With Matindok Field as the core, Maleoraja Field plays a complementary role, and Sukamaju Field enables the maximum utilisation of processing capacity. While these gas fields share common geological structures, each has unique reservoir characteristics, and integrated development achieves overall optimisation.

Midstream Processing Facilities (CPP)

Senoro CPP

1. Basic Specifications

• Design capacity: 250 MMSCFD
• Start of operation: June 2015
• Operator: JOB Pertamina-Medco E&P Tomori Sulawesi
• Location: Within Senoro-Toili Block
• Investment: Undisclosed

2. Main Processing Technologies

• Acid Gas Removal Unit (AGRU): Using MDEA solvent
• Dehydration Unit (DHU): Quality improvement through moisture removal
• Biological Sulfur Recovery Unit (BSRU): Environmental load reduction
• Condensate separation and treatment system
• Gas measurement and quality control system

3. Processing Capacity and Production Performance

• Design processing capacity: 250 MMSCFD
• Operating processing capacity: Consistently achieving design values
• Main products: Refined natural gas, condensate, sulfur
• Quality standards: LNG manufacturing and ammonia manufacturing specifications

Senoro CPP has played a central role in regional energy supply since starting operations in June 2015 as the pioneering natural gas processing facility in the Central Sulawesi region. The large-scale processing capacity of 250 MMSCFD is a strategic design to maximise the utilisation of production capacity from the Senoro Field, the region’s largest gas field. The acid gas removal unit utilises an advanced system employing MDEA (Methyldiethanolamine) solvent, resulting in the efficient removal of CO2 and H2S.

Donggi CPP

1. Basic Specifications

• Design capacity: 60 MMSCFD
• Start of operation: April 2016
• Operator: PT Pertamina EP
• Location: Toili Barat District
• Investment: US$762 million (combined with Matindok CPP)

2. Main Processing Technologies

• Acid Gas Removal Unit (AGRU): High impurity compatible specifications
• Dehydration Unit (DHU): High-efficiency dehydration system
• Sulfur recovery unit: Environmental response technology
• Condensate treatment system
• High-pressure gas compression system

3. Processing Capacity and Production Performance

• Design processing capacity: 60 MMSCFD
• Operating processing capacity: 105 MMSCFD integrated with Matindok CPP
• Main products: Refined natural gas, condensate (approximately 850 bpd)
• Quality standards: DSLNG supply specifications

Donggi CPP is designed explicitly for processing gas with high impurity content, which corresponds to the unique feedstock gas characteristics of the Donggi and Minahaki Fields. Since starting operations in April 2016, it has made significant contributions to expanding regional natural gas processing capacity. The acid gas removal unit is designed with high impurity compatibility specifications, enabling the efficient removal of sulfur compounds and carbon dioxide. Integrated operation with Matindok CPP ensures resistance to single-facility shutdowns and establishes a stable supply system for downstream facilities.

Matindok CPP

1. Basic Specifications

• Design capacity: 65 MMSCFD
• Start of operation: April 2017
• Operator: PT Pertamina EP
• Location: Batui District
• Investment: US$762 million (combined with Donggi CPP)

2. Main Processing Technologies

• Acid Gas Removal Unit (AGRU): Latest technology adoption
• Dehydration Unit (DHU): High-efficiency specifications
• Biological Sulfur Recovery Unit (BSRU): Environment-conscious type
• Green Plant technology: Environmental load minimisation
• Integrated control system: Efficient operation management

3. Processing Capacity and Production Performance

• Design processing capacity: 65 MMSCFD
• Integrated processing capacity: 105 MMSCFD (combined with Donggi CPP)
• Main products: Refined natural gas, condensate
• Quality standards: DSLNG supply specifications
• Integrated supply: Connected to the main pipeline via TIP1/TIP2

Matindok CPP is positioned as the completion form of the regional natural gas processing facility group, with the integrated supply system completed upon starting operations in April 2017. The Green Plant concept, incorporating the latest environmental technology, achieves both minimisation of environmental load and maximisation of operational efficiency. Integrated operation with Donggi CPP achieves technical synergy and improved operational efficiency, with a 105 MMSCFD processing capacity that meets regional natural gas demand. The TIP1/TIP2 integrated system enables integration with Senoro CPP, securing a total comprehensive supply capacity of 335 MMSCFD for the entire region.

Downstream Utilisation Facilities

LNG Facilities

1. Donggi-Senoro LNG (DSLNG)

• Processing capacity: 2 MTPA (Million Tonnes Per Annum)
• Location: Banggai Regency, Central Sulawesi
• Start of operation: June 24, 2015
• First shipment: August 2, 2015 (with presidential attendance)
• Investment: Approximately US$2.5 billion

2. Gas Supply Structure

• Senoro CPP supply: 250 MMSCFD
• Matindok/Donggi integrated supply: 85 MMSCFD
• Total supply: 335 MMSCFD
• Supply contract period: Until 2027 (long-term contract)

3. Technical Specifications

• Liquefaction technology: Mixed Refrigerant Process
• Storage tanks: 2 units (160,000m³ each)
• Shipping facilities: Dedicated jetty and loading arms
• Annual production: Approximately 2 million tons

DSLNG is the first integrated downstream LNG project in Indonesia, adopting a strategic business model that enables simultaneous revenue generation from both upstream and downstream activities. Since starting operations in 2015, it has continued stable operations and functions as a major LNG supply source to the Asia-Pacific region. The adoption of the Mixed Refrigerant Process enables efficient liquefaction processes and competitive LNG production.

Fertiliser Facilities (Ammonia Plant)

1. PT Panca Amara Utama (PAU)

• Production capacity: 660,000 tons per year (ammonia)
• Location: Adjacent to DSLNG Terminal
• Start of operation: 2013
• Investment: Approximately US$800 million

2. Natural Gas Consumption

• Consumption: 55 MMSCFD
• Supply source: Senoro CPP
• Supply method: Via a 23km pipeline
• Contract period: 13 years (2015-2027)

3. Production and Sales Structure

• Main products: Ammonia (fertiliser raw material)
• Sales market: Domestic market + export
• Employment creation: Approximately 1,000 people
• Annual sales: Approximately US$300 million

PAU plays a crucial role in promoting regional industrialisation and job creation by producing ammonia using natural gas as a feedstock. The location adjacent to the DSLNG Terminal simultaneously ensures the convenience of natural gas supply and the efficiency of product transportation. The 13-year long-term gas supply contract guarantees predictable plant operation and stable investment recovery.

Power Generation Facilities

1. PLTMG Luwuk (40 MW)

• Generation capacity: 40 MW
• Location: Nonong Village, Banggai Regency
• Start of operation: January 2025
• Investment: Rp521 billion (approximately US$35 million)

2. Power Generation System

• Number of engines: 5 gas engines
• Generation method: Gas Engine Power Plant (PLTMG)
• Fuel: Natural gas (5 MMSCFD)
• Efficiency: Approximately 8,000-10,000 BTU/kWh

3. Power Supply Capacity

• Household supply: 30,000 households
• Industrial demand: 30 MW
• Grid connection: 150 kV substations (Luwuk, Batui)
• CO2 reduction: 75,000 tons per year

4. Gas Supply Contract

• Contractor: JOB Tomori (Senoro CPP operator)
• Supply volume: 5 MMSCFD

Integrated System and Structure

The Central Sulawesi natural gas development project has established a complex, integrated system that strikes a balance between technical efficiency and commercial stability. Centred on the 23km main pipeline from Senoro CPP (capacity 310 MMSCFD), efficient allocation is performed to DSLNG (250 MMSCFD), PAU (55 MMSCFD), and PLTMG Luwuk (5 MMSCFD).

The TIP1/TIP2 integration points serve as technical keystones. The 85 MMSCFD from the Matindok/Donggi region is connected to Senoro CPP’s main pipeline through these integration points via 35 km and 1 km feedstock gas transportation pipelines, achieving a total comprehensive supply capacity of 335 MMSCFD for the entire region. This integration enables the centralised management of natural gas from multiple supply sources and ensures resilience against single facility shutdowns.

Conclusion

The Central Sulawesi natural gas development project has established an integrated value chain, spanning from diverse upstream gas field development to diversified downstream utilisation, making significant contributions to regional economic growth and national energy security. The accumulation of operational experience through chronological development, supply stability assurance through integrated systems, and revenue maximisation through diverse downstream utilisation are the primary success factors.