PROCESS DESCRIPTION DETAILS(GGS):The process flow sequence is shown in the Process Flow Diagram (PFD) No ADB/T153C01001/G00/A1-03.All the fluids from the wells will be fed to GCS well manifold headers are provided to receive the well fluid, viz.a) H.P Header.b) M.P Header.c) Test Header.All the wells are connected too all the headers with isolation valves for interchange ability.H.P HEADER:The H.P Header will receive gas along with condensate and water from high-pressure wells. The gas and liquid from this header flows via bath header (E 101A) into the H.P 3 phase Separator (V 101), which is to be maintained at 60 kg/cm2 g. The fluid is to be heated up to 35c before sending into the H.P Separator.The gas from the H.P Separator will flow to Gas Scrubber (V 103) at 24 kg/cm2 g for further processing. The gas from the Gas Scrubber (V 103) flows to the Filters (F 101 A/B) to supply liquid free gas to the consumer after measurement.The condensate and water from the H.P Separator (V 101) are received in condensate Separator (V 104) and Effluent Water Stabilizer (V 106) at 26 kg/cm2 g & 1.5 kg/cm2 g respectively for stabilization.The condensate from Condensate Separator (V 104) flows to Condensate Stabilizer (V 105) for further stabilization at 1.5 kg/cm2 g. Finally the condensate from (V 105) is sent storage tanks (T 101 A/B).The effluent water from the Effluent water stabilizer (V 106) is sent to Effluent Water Evaporation pit (T 111 A/B) after stabilization for onward disposal. Inclusion of Additional Facilities:Additional facility has been added to the process as attachments to increase the capacity of the plant. Addition of Scrubber: The gas from the H.P Separator will flow to the additional Gas Scrubber (S-0301) at operating pressure 25kg / cm2 for further processing. Addition of filter: The gas from the additional Gas Scrubber (S-0301) further flows to newly added additional filter (F0302 A/B) to supply liquid free gas to the consumer after measurement.Addition of Flare Knock out Drum to the flare system: A flare knock out drum (SD-7) is added to the flare System. The flare gas will flow to the flare Knock out Drum (SD-7) via 12 flare header. Both the knock out drum (V-108 & SD-7) is installed parallel to each other with common facility of existing pumps of (P108 A/B) to extract out the condensate through condensate drain line.M.P HEADER:The M.P Header will receive gas along with condensate and water from medium pressure wells. The well fluid is directly sent to the MP 3 phase Separator (V 102), which is to be maintained at 28 kg/cm2 g.The gas released from M.P Separator (V 102) is sent to gas scrubber at 24 kg/cm2 g for further processing. The gas from the V 103 flows to Filters (F 101 A/B) to supply liquid free gas to the Consumer after measurement.The Condensate & Produced water flow path shall be similar to the H.P Section. TEST HEADER: This is meant for testing of individual wells. The operation pressure shall be 60kg/cm2 g or lower up to 28 kg/cm2 g depending upon the pressure of the wells to be tested. The gas and liquid from this header flows via Bath Heater (E 101B) into the Test 3 phase separator (V 107). This separator may be used to standby of V 101 or V 101 in case of shut down of these separators.The gas from the Test Separator (V 107) will flow to Gas Scrubber (V 103) at 24 kg/cm2 g for further processing. The gas from the Gas scrubber (V 103) flows to Filters (F 101 A/B) to supply liquid free gas to the consumer after measurement.The condensate and produced water flow path shall be similar to the H.P Section.INDIRECT BATH HEATING:An indirect Bath Heater (E 101A) is used to heat the H.P Header fluid Stream up to 35C at 60 kg/cm2 g pressure. Then the fluid is fed into H.P Separator (V 101). There should not be any hydrate formation in subsequent reduction of of pressure if indirect bath heater is used to heat the gas stream.

Capacity Enhancement of ADB GCS ADB GCS is a gas process installation of Tripura Asset currently supplies gas to ONGC Tripura Power Company (OTPC) Palatana, North East Power Co. (NEEPCO) Ramchandra Nagar, Piped Natural Gas (PNG) network of Agartala city & CNG stations. Designed process capacity of GCS is 2.2 MMSCMD of gas, 52.3 m/day of Condensate and 52.8 m/day of produced effluent water.Presently 18 gas wells (including 2 wells from Kunjaban Field) are flowing to ADB GCS.For processing of gas, one no of HP Separator, MP Separator, Test Separator, Gas Scrubber, two Main Gas Filters, one no of Condensate Separator, Condensate Stabilizer, Effluent Stabilizer & Flare KOD are in use to meet quality requirement.Based on the latest test rates of well, total production potential of 18 wells is 2.43 MMSCMD of gas. As latest production profile indicates peak gas production of 2.71 MMSCMD as few more wells have been planned for drill in this area, IOGPD has recommended for de-bottlenecking of handling process capacity of ADB GCS.As Tripura Asset has commitment to supply 2.65 MMSCMD of gas to OTPC Palatana & 0.5 MMSCMD of gas to NEEPCO Monarchak along with old customers i.e. TSECL Rokhia, Baramura, NEEPCO Ramchandra Nagar & TNGCL requires daily gas supply of 4.96 MMSCMD.Under the above circumstances, in order to meet the shortfall of gas requirement at Monarchak & as per IOGPT recommendation following additional process facilities need to be created at ADB GCS at earliest. It has also been discussed and decided that following vessels, pipes, valves & fittings of Sonamura GGS may be taken to meet the immediate requirement of ADB & the same will be returned to Sonamura Project after procurement against ADB Capacity Enhancement Project. Major vessels, pipes & valves are as follows:A. Gas Scrubber One No.B. Main Gas Filter Two Nos.C. Flare KOD (From Konaban) One No.D. Valve-1/2/4/8/10/12etc.E. Pipes & Fittings 2, 3, 4, 6, 8, 10, 12 etc.Brief Scope of Work:Total job will include the following:1. Design engineering Support.2. Civil Foundation of Vessels (Scrubber, Filter, KOD)3. Civil work for Trestles & Sleepers.4. Foundation for platforms.5. Extension of Control Room Building for facilitate new Panels, UPS, and Battery etc. with provision of future ETP6. Structural fabrication & erection of trestles, platforms etc.7. Separate piping train.8. Complete instrumentation with new PLC panel.9. Provision for new future separator.10. Installation of 3 nos. Gas Detector at Process area.11. Sprinkler system around flare stacks to compensate radiation level.12. Replacement of existing ANNUBAR with Thermal Mass Flow Meter in Flare Header.13. Integration of new vessels with existing process train including instrumentation system.14. New MCC Panel for electrical connection.15. New 10 KVA UPS.16. Illumination for new facilities.17. Enhancement of existing fire fighting system with additional water monitors & water hydrant with hose box.18. Procurement of vessels and other materials to compensate Sonamura Project.19. Fabrication, erection, hook-up, testing, pre-commissioning & commissioning of new additional facility.

Process Schematic:Flow lines from individual wells are connected to the well manifold. Three headers are provided in the inlet manifold to receive the well fluids. HP Header

MP Header

Test Header

Well fluid from HP header is routed to HP separator (V-101)which is maintained at 60 kg/cm2.Theprovisionofthebathheaterisprovidedtopre-heattheinletwellfluidup to 35C. Fluid from the MP header enters into MP Separator (V-102),which is maintained at28-29 kg/cm2.The well fluid from the test header is routed to the Test separator(V-107) which is operated between 28 to 60 kg/cm2as per the well-head pressures. The gas from HP, MP and Test separators flow to gas Scrubber (V-103) through a common header which is operating at24-25.0kg/cm2.The liquid free gas from the gas scrubber after passing through gas filters (F 101 A/B) is supplied to the Consumers. Additional process facility will introduce after the separators. Process gas from separators will flow to new scrubber from the common header. Flow shall be controlled (0.5 MMSCMD) by a Flow Control Valve followed by a FIT. The gas from Gas Scrubber shall pass through Gas Filters. The liquid free processed gas (0.5 MMSCMD) will be hooked up with existing header after existing Gas Filters & Supplied to Customers.The condensate from the separators(V-101, V-102andV-107) flows to condensate stabilizer (V-104).The vessel(V-104) is maintained at a pressure of 26kg/cm and the evolved gas flowstoV-103.The condensate from the separator(V-104)along with liquid fromV-103 flows to the condensate stabilizer(V-105)whichisoperatedat2.5kg/cm and the evolved gasutilisedforinternalconsumption.ThestabilizedcondensatefromV105issenttothe tanks(T101A/B)for storage and subsequent despatch by tankers.Condensate from new Scrubber Shall be terminated through 2 line in existing condensate header before Condensate Stabilizer (V-105).

The effluent water from the separators (V-101,V-102& V107) flows to the water stabilizer (V-106). This vessel is maintained at a pressure of 2.5kg/cm2 and the evolved gas utilised for internal consumption. The effluent water from V-106 after stabilization is sent to evaporation pits for further treatment and internal utilisation.A separate flare sub-header will transport flare gases from new system & shall be terminated to new Flare KOD (KOD from Konaban). The out let of KOB shall be terminated to existing 20 flare header after existing Flare KOD with a future provision of new flare stack.