Condensate

Condensate Condensate is a hydrocarbon mixture that exists in gaseous state in the subsurface under high reservoir pressure condition but condenses into liquid when produced at the surface because of lowering of pressure. Most condensates are composed of saturated hydrocarbons in the light gasoline range (butane, pentane and hexane). It is generally light yellow to colorless, lighter than light oil having API gravity higher than 55 degree. Gas produced from a field containing significant quantities of condensate is characterised as wet gas. Condensate may have several mode of origin. [1] from organic matter (kerogen) as an intermediate product between oil and gas. [2] from conversion of oil to gas in a reservoir [3] from the gas phase migration of hydrocarbon out of an oil pool by vaporization or gas stripping.(Hunt 1996).

Majority of the gas fields of Bangladesh produce dry gas and little condensate. Yet some fields produce significant amount of condensate. The three most condensate rich gas fields are Beanibazar (18 barrel/mmcfg), Jalalabad (15 barrel/mmcfg) and Kailashtila(11barrel/mmcfg).Total initial reserve of condensate in Bangladesh' is 43.2 million barrel of which 63% is reserved in these three condensate rich fields and they produce major part of the total condensate production in the country. The total daily production is about 3444 barrel, 50% of wehich comes from only one field, Jalalabad. By June 2002, about 10.4 million barrel of condensate has been produced leaving a remaining reserve of about 32.8 million barrel.

Table Condensate rerves and production in developed gas fields of Bangladesh.

Gas field	App. condensate to gas ratio (bbl/mmcf)	Initial reserve (million barrel)	Cumulative production till June 2002 (million barrel)	Daily production in July 2004 (barrel/day)
Kailashtila	10.90	12.94	4.01	549
Jalalabad	15.00	12.00	1.39	1708
Beanibazar	18.00	2.53	0.20	381
Sylhet	3.34	0.96	0.58	19
Rashidpur	3.05	3.54	0.39	117
Bakhrabad	2.45	2.14	0.89	18
Titas	1.43	6.81	2.65	507
Shaldanadi	3.00	0.74	0.02	13
Narsinghdi	2.46	0.17	0.08	44
Meghna	2.01	0.20	0.05	4
Habiganj	0.05	0.09	0.05	18
Fenchuganj	2.47	0.65	-	10
Sangu	n/a	n/a	0.07	54
Chattak	0.07	0.01	-	suspended
Feni	3.00	0.30	0.09	suspended
Kamta	0.20	0.004	0.004	suspended
Total		43.23	10.44	3444

Source www.petrobangla.org.bd.

The condensate produced from the gas fields is transported through pipelines to the processing plants and refined. Approximately 38,000 ton of condensate is supplied annually from different gas fields of the country to the eastern refinery limited for producing refined petroleum products. The condensate produced from the gas fields are piped by a six-inch diameter and 175 km long pipeline from Kailashtila to Ashuganj and then transported to Eastern Refinery at Chittagong by barges.Condensate is processed in NGL fractionation plant to produce LPG, motor spirit and kerosene and are used in the local market. [Mushfiqur Rahman]