Assignment – 2
For
Understanding
Natural Gas Business
Buy Now from this Link
Section A (20 Marks)
Write short notes
on any four of the following:
1.
Principles of separation
2.
Usefulness of Compressed Natural Gas
3.
Significance of GTL technology
4.
Comparison of LPG with other
fuels
5.
Role of natural gas in global
energy
Section B (30 marks)
(Attempt any three)
1.
Briefly explain the
synchronization of regasified LNG with distribution pipelines.
2.
Discuss the improvement of
tools for hydromechanic basic design.
3.
Why Coal Bed Methane (CBM) is
considered to be the most hazardous item in Coal Mining operation?
4.
What factors need to be
considered while deciding for converting diesel or petrol operated fleet into
CNG operated vehicle?
Section C (50 marks)
(Attempt all questions. Every question carries 10 marks)
Read the case “Russian
Classification of Reserves” and answer the following questions:
Case Study: Russian Classification of Reserves
The estimation of reserves of natural
gas, gas condensate and crude oil can be broken down into two components: (i)
geological reserves, or the quantities of natural gas, gas condensate and crude
oil contained in the subsoil and (ii) extractable reserves, or the portion of
geological reserves whose extraction from the subsoil as of the date the
reserves are calculated is economically efficient given market conditions and
rational use of modern extraction equipment and technologies and taking into account
compliance with the requirements of subsoil and environmental protection.
The Russian reserves system is based
solely on the analysis of geological attributes. Explored reserves are
represented by categories A, B, and C1; preliminary estimated reserves are
represented by category C2; potential resources are represented by category C3;
and forecasted resources are represented by categories D1 and D2. Natural gas
reserves in categories A, B and C1 are considered to be fully extractable. For
reserves of oil and gas condensate, a predicated coefficient of extraction is
calculated based on geological and technical factors.
Category A reserves are calculated on the
part of a deposit drilled in accordance with an approved development project
for the oil or natural gas field. They represent reserves that have been
analyzed in sufficient detail to define comprehensively the type, shape and
size of the deposit; the level of hydrocarbon saturation; the reservoir type;
the nature of changes in the reservoir characteristics; the hydrocarbon
saturation of the productive strata of the deposit; the content and
characteristics of the hydrocarbons; and the major features of the deposit that
determine the conditions of its development (mode of operations, well
productivity, strata pressure, natural gas, gas condensate and crude oil
balance, hydro and piezo-conductivity and other features). http://distpub.in/index.php/cPath/50_58
Category B represents the reserves of
a deposit (or portion thereof), the oil or natural gas content of which has
been determined on the basis of commercial flows of oil or natural gas obtained
in wells at various hypsometric depths. The type, shape and size of the
deposit; the effective oil and natural gas saturation depth and type of the
reservoir; the nature of changes in the reservoir characteristics; the oil and
natural gas saturation of the productive strata of the deposit; the composition
and characteristics of crude oil, natural gas and gas condensate under in-situ
and standard conditions and other parameters; and the major features of the
deposit that determine the conditions of its development have been studied in
sufficient detail to draw up a project to develop the deposit.
Category B reserves are computed for
a deposit (or a portion thereof) that has been drilled in accordance with
either a trial industrial development project in the case of a natural gas
field or an approved technological development scheme in the case of an oil
field.
Category C1 represents the reserves
of a deposit (or of a portion thereof) whose oil or natural gas content has
been determined on the basis of commercial flows of oil or natural gas obtained
in wells (with some of the wells having been probed by a formation tester) and
positive results of geological and geophysical exploration of non-probed wells.
The type, shape and size of the
deposit and the formation structure of the oil- and gas-bearing reservoirs have
been determined from the results of drilling exploration and production wells
and by those geological and geophysical exploration techniques that have been
field-tested for the applicable area. The lithological content, reservoir type
and characteristics, oil and natural gas saturation, oil displacement ratio and
effective oil and natural gas saturation depth of the productive strata have
been studied based on drill cores and geophysical well exploration materials.
The composition and characteristics of crude oil, natural gas and gas
condensate under in-situ and standard conditions have been studied on the basis
of well testing data. In the case of an oil and natural gas deposit, the
commercial potential of its oil-bearing fringe has been determined. Well
productivity, hydro- and piezo-conductivity of the stratum, stratum pressures
and crude oil, natural gas and gas condensate temperatures and yields have been
studied on the basis of well testing and well exploration results. The
hydro-geological and geocryological conditions have been determined on the
basis of well drilling results and comparisons with neighboring explored
fields.
Category C1 reserves are computed on
the basis of results of geological exploration work and production drilling and
must have been studied in sufficient detail to yield data from which to draw up
either a trial industrial development project in the case of a natural gas
field or a technological development scheme in the case of an oil field.
Category C2 reserves are preliminary
estimated reserves of a deposit calculated on the basis of geological and
geophysical research of unexplored sections of deposits adjoining sections of a
field containing reserves of higher categories and of untested deposits of
explored fields. The shape, size, structure, level, reservoir types, content
and characteristics of the hydrocarbon deposit are determined in general terms
based on the results of the geological and geophysical exploration and
information on the more fully explored portions of a deposit. Category C2
reserves are used to determine the development potential of a field and to plan
geological, exploration and production activities.
Category C3 resources are prospective
reserves prepared for the drilling of (i) traps within the oil-and-gas bearing
area, delineated by geological and geophysical exploration methods tested for
such area and (ii) the formation of explored fields which have not yet been
exposed by drilling. The form, size and stratification conditions of the
assumed deposit are estimated from the results of geological and geophysical
research. The thickness, reservoir characteristics of the formations, the
composition and the characteristics of hydrocarbons are assumed to be analogous
to those for explored fields. Category C3 resources are used in the planning of
prospecting and exploration work in areas known to contain other reserve
bearing fields.
Category D1 resources are calculated
based on the results the region’s geological, geophysical and geochemical
research and by analogy with explored fields within the region being evaluated.
Category D1 resources are reserves in lithological and stratigraphic series
that are evaluated within the boundaries of large regional structures confirmed
to contain commercial reserves of oil and natural gas.
Category D2 resources are calculated
using assumed parameters on the basis of general geological concepts and by
analogy with other, better studied regions with explored oil and natural gas
fields. Category D2 resources are reserves in lithological and stratigraphic
series that are evaluated within the boundaries of large regional structures
not yet confirmed to contain commercial reserves of oil and natural gas. The
prospects for these series to prove to be oil-and gas-bearing are evaluated
based on geological, geophysical and geochemical research.
The evaluation of natural gas
reserves in newly discovered natural gas or oil-and-gas deposits is carried out
under the Russian reserves system using the volume method. The volume method
determines the volume of reserves by examining the filtration and capacitive
parameters of the deposit based on (i) the area of the deposit; (ii) the
effective depth of hydrocarbon saturation; and (iii) the porousness of the
deposit and the level of saturation of the hydrocarbons, taking into account
thermobaric conditions.
The evaluation of natural gas
reserves in deposits already under development is carried out under the Russian
reserves system using both the volume method and the material balance method.
The material balance method takes into account temporal changes in the
effective reservoir pressure as a result of the extraction of the hydrocarbons
and the resultant influx of water.
In accordance with the Law on Subsoil
mineral reserves in Russia are subject to mandatory state examination, and
subsoil users cannot be granted a production license with respect to a field
that was not examined. The state examination of reserves is conducted by
subsidiary organizations of the Federal Agency on Subsoil Use, including the
State Reserve Commission, Central Reserve Commission and its regional
departments. If the commercial feasibility of certain reserves is approved by
any such organization, the reserves are entered in the State Balance of Mineral
Products. Once a subsoil user is granted an exploration, development or
production license, it is required to file annual statistical reports
reflecting changes in reserves. In addition, subsoil users’ reserve reports are
submitted annually for examination and approval by the Central Reserve
Commission or its regional organizations or, if there has been a substantial
change in reserves, by the State Reserve Commission.
Estimation of reserves, as examined
by the state expert organizations and reflected in subsoil users’ annual
statistical reports, is accumulated in the State Balance of Mineral Products.
Questions:
1.
Find out the case facts of the
above case.
2.
On what grounds are the
reserves classified?
3.
According to you, which is the
best Category of reserves? Support your answer with reasons.
4.
Discuss the utility of volume
method in determining the evaluation of
natural gas reserve.
5.
Give a brief conclusion to the
case study.
No comments :
Post a Comment