Managing Gas Export Manifold To Ensure Gas Deliverability
Authors: Priambudi Alfin , Baraba Rifki Naji , Tranggono Nanangwasis , Aryanto Budi 
Published: May 2016

The Badak Export Manifold (BEM) is a complex manifold to gather the entire gas delivery from upstream fields and to deliver hydrocarbons to Liquefied Natural Gas (LNG) plant and to domestic commercial sites, manufacturing fertilizers and chemicals. Besides the function as gas processing facilities, the duties of the export manifold are to maintain pressure, distribute gas flow, implement off take logic during shut down and coordinate gas delivery. The BEM is the beginning of four main pipelines work in parallel configuration to allow flexibility of the gas delivery and to maintain gas composition within acceptable specification.

The pressure stability and gas specification are the important aspect of the export manifold operations. These operations become challenging tasks because of the changing of the upstream fields' condition. The pressure was decreased and the gas composition became richer, not to mention gas supply was less than gas demand as well as pipelines capacity. A quick decision and field action should be taken immediately to avoid plant shut down and gas composition out of consumers' specification.

In addition to gas composition become richer, hilly terrains of the pipelines create liquid hold up (LHU) in the pipelines. The LHU will increase the back pressure to upstream field, and as consequences the plant with natural gas flow from well will be restricted. Despite the flexibility of the supply, the parallel operations of the pipelines make gas flow tend to go to the line which has less back pressure. The BEM takes an important part in the attempt to sweep liquid in the parallel mode by segregating gas flow into particular pipeline.

Many efforts have been performed to improve export manifold operations. It was included establishing a clear operation guideline during normal and emergency situations, adjusting operations parameter to minimize unnecessary shut down, and installing additional equipment to allow remote operations of safety equipments within export manifold area. Nowadays, almost all of the BEM parameters can be monitored remotely to support better operation.

1. Introduction

VICO Indonesia is one of East Kalimantan gas producers and producing about 405 MMscfd of natural gas, and 18,000 bpd oil and condensate from four production fields. They also take a role as gas production coordinator and pipeline custodian for all producers, and responsible to deliver approximately 2.9 Bscfd natural gas from many fields in East Kalimantan, which owned by different oil and gas company i.e. Total E&P Indonesie, Chevron Ind. Co., and Chevron Makassar. The gas amount is very significant for government of Indonesia because it is accountable for 37.7% of national gas production (1.215.224 MMscf) and 67.5% of national LNG production (16.323.195 M.Ton). Most of the gas is delivered to PT Badak at Bontang where LNG and LPG are produced and shipped to Japan, Korea and Taiwan. Smaller volumes of gas are supplied to fertilizer, ammoniac and methanol plant at the Kaltim Industrial Estate.

The Pipeline Operations and Maintenance Agreement (POMA) require VICO to maintain, operate and inspect more than 1000 km of pipelines with the range diameter of 3" to 42". The East Kalimantan pipeline network system is designed to transfer hydrocarbons from outlying producer's processing facilities to Bontang Liquefied Natural Gas (LNG) facility and to other commercial sites, fertilizer and chemical plants in Kaltim Industrial Estate (KIE).