U.S. patent application number 15/465203 was filed with the patent office on 2017-07-06 for apparatus for washing rock samples.
The applicant listed for this patent is Rockwash Prep & Store Ltd. Invention is credited to Rae JONES, Michael Gerard SNAPE.
Application Number | 20170191908 15/465203 |
Document ID | / |
Family ID | 44012838 |
Filed Date | 2017-07-06 |
United States Patent
Application |
20170191908 |
Kind Code |
A1 |
SNAPE; Michael Gerard ; et
al. |
July 6, 2017 |
Apparatus for Washing Rock Samples
Abstract
An apparatus for washing rock samples, which is particularly
suited to the washing and preparation of rock samples obtained from
oil and gas wells. In one embodiment there is provided a method of
washing rock samples involving a plurality of discrete rock
samples; providing a plurality of sequentially arranged discrete
washers each of which is spaced from a respective washing position
and configured to direct a washing flow of water towards said
washing position; and automatically conveying said samples relative
to said washers so that each sample moves in succession through
said washing positions for sequential washing by each said
washer.
Inventors: |
SNAPE; Michael Gerard;
(Chester, GB) ; JONES; Rae; (South Wales,
GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Rockwash Prep & Store Ltd |
Gwent |
|
GB |
|
|
Family ID: |
44012838 |
Appl. No.: |
15/465203 |
Filed: |
March 21, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13073427 |
Mar 28, 2011 |
9651461 |
|
|
15465203 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B08B 3/022 20130101;
E21B 49/02 20130101; G01N 33/24 20130101; G01N 1/34 20130101; E21B
21/066 20130101 |
International
Class: |
G01N 1/34 20060101
G01N001/34; G01N 33/24 20060101 G01N033/24; B08B 3/02 20060101
B08B003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 18, 2011 |
GB |
1104654.7 |
Claims
1. An apparatus for washing rock samples for subsequent analysis
and derivation of geological information from the rock samples, the
apparatus comprising a plurality of sequentially arranged and
equi-spaced discrete washers, each of which is spaced from a
respective washing position and configured to direct a washing flow
of water towards said washing position; a plurality of sequentially
arranged and equi-spaced discrete dryers each of which comprises a
heater arranged to direct heat towards a respective drying
position; and a conveyor operable to automatically convey a
plurality of discrete rock samples, in succession, relative to said
washers in a step-wise manner such that each sample moves through
said washing positions for sequential washing by each said washer,
wherein each said sample remains stationary, relative to each said
washer, in each said respective washing position for an equal and
predetermined washing period during which said respective washer is
operable to wash the sample by said respective washing flow of
water, and is moved by an index distance between successive said
washing periods; the conveyor also being operable to automatically
convey said samples, in succession, relative to said dryers in a
step-wise manner so that each sample moves through said drying
positions for sequential drying by each said dryer, wherein each
said sample remains stationary, relative to each said dryer, in
each said drying position for an equal and predetermined drying
period, and is moved by said index distance between successive said
drying periods; wherein each said index distance is equal to the
distance by which said washers are equi-spaced apart and is equal
to the distance by which said dryers are equi-spaced apart.
2. An apparatus according to claim 1, wherein said plurality of
washers comprise at least one washer that is connected to a supply
of fresh water so as to produce a washing flow of fresh water.
3. An apparatus according to claim 1 wherein said plurality of
washers comprise at least one washer that is connected to a
recirculated flow of water.
4. An apparatus according to claim 3, wherein the at least one
washer that is supplied with fresh water is arranged sequentially
after a washer that is supplied with recirculated water.
5. An apparatus according to claim 3, comprising a plurality of
washers connected to said recirculated flow of water and a single
washer connected to said supply of fresh water.
6. An apparatus according to claim 3 further comprising at least
one filter through which said recirculated flow of water
passes.
7. An apparatus according to claim 3 comprising a weir over which
said recirculated flow of water passes.
8. An apparatus according to claim 3 further comprising a pump
operable to pump said recirculating flow of water to said
washers.
9. An apparatus according to claim 1, wherein each said heater
comprises an infrared lamp.
10. An apparatus according to claim 1, further comprising agitating
means operable to automatically agitate each sample as it is moved
through said drying positions.
11. An apparatus according to claim 10, further comprising a
plurality of receptacles, each receptacle being configured for the
receipt of a respective sample and wherein each of said receptacles
permits water remaining on each of the samples to drain, and
wherein said agitating means comprises a mechanism operable to
engage and oscillate said receptacles.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present invention is a Divisional Application of U.S.
application Ser. No. 13/073,427, filed Jun. 9, 2016, the
disclosures of which are incorporated herein by reference in their
entirety.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to a method and an associated
apparatus for washing rock samples, and is particularly suited to
the washing and preparation of rock samples obtained from oil and
gas wells.
DESCRIPTION OF THE PRIOR ART
[0003] The importance and value of geological data derived from
rock-samples retrieved from oil & gas drilling operations has
increased tremendously in recent years. This reflects the inflated
costs of global drilling operations, particularly in new and
challenging environments, such as ultra-deep water and difficult
onshore areas. The speed and quality of well data generation is a
key commercial factor because multi-million dollar drilling
decisions are being made on the basis of the new geological data
generated from these rock samples.
[0004] Needless to say, health and safety remains paramount for the
oil and gas companies around the world. Furthermore, in recent
years, environmental considerations of the drilling process and
subsequent geological analysis has come under considerable scrutiny
by the world at large.
[0005] Rock samples from oil and gas wells are generated during the
drilling process. The drill bit cuts and grinds rocks as the
well-bore penetrates the geological strata at depth, pulverising
the strata into small rock fragments. These small rock fragments
are commonly referred to as "ditch-cuttings" or just "cuttings. At
set intervals, these ditch-cuttings are circulated from the bottom
of the well to the surface, by suspension within the circulating
"drilling mud" which acts as a drilling lubricant within the well.
The resulting ditch-cuttings samples therefore arrive at the
surface as dirty fragments of rock covered in drilling mud.
[0006] On occasion, a drilling company might recover whole-core
samples in the form of long cylindrical lengths of cored rock, or
side-wall core samples from the same well bore. However, as
drilling costs continue to rise, there is a tendancy to take these
sorts of samples less frequently than has been the case in the
past. This places greater emphasis on the preservation and analysis
of the more commonly obtained ditch-cuttings samples from new and
old archived wells alike.
[0007] Rock samples in the form of dirty ditch-cuttings thus
commonly form the basis for subsequent geological analysis. There
is therefore a need to clean these samples from all drilling
contaminants, in order for important geological information to be
derived. Also, after analysis the samples must be correctly and
reliably labelled so that the well operator company and service
companies studying the samples know the exact identity and location
of the well from which the sample was taken, and the depth at which
it was obtained.
[0008] Presently, rock samples obtained as ditch cuttings are
washed manually using steel or brass sieves. Each individual sample
is placed in a respective sieve (typically approximately 20 cm in
diameter) and run under a flow of fresh water from a shower head or
the like. The sample is mixed with detergent and agitated by hand
under the flow of water until the water runs clear through the base
of the sieve. The washed sample is then transferred to an
individual container for drying, either on a hotplate or in an
oven.
[0009] As will be appreciated, the prior art washing method
explained above is extremely labour-intensive and time consuming.
This can be very limiting indeed when many samples are obtained
from each well. For example, generally 300-500 individual rock
samples are obtained from a single well, and sometimes this number
can be as high as 900. Also, the prior art method is very wasteful
of water.
SUMMARY OF THE INVENTION
[0010] It is an object of the present invention to provide an
improved method for washing rock samples.
[0011] It is another object of the present invention to provide an
improved apparatus for washing rock samples.
[0012] According to a first aspect of the present invention, there
is provided a method of washing rock samples, the method comprising
the steps of: providing a plurality of discrete rock samples;
providing a plurality of sequentially arranged discrete washers
each of which is spaced from a respective washing position and
configured to direct a washing flow of water towards said washing
position; and automatically conveying said samples relative to said
washers so that each sample moves in succession through said
washing positions for sequential washing by each said washer.
[0013] Preferably the method comprises the supply of substantially
fresh water to at least one of said washers.
[0014] Advantageously, the method comprises the step of collecting
water used to wash said samples in each said washing position and
recirculating the water for supply to at least one of said
washers.
[0015] Conveniently, said step of automatically conveying the
samples relative to said washers comprises moving each said sample
through the washing position associated with the or each washer
supplied with recirculated water before the washing position
associated with the or each washer supplied with fresh water.
[0016] Preferably a plurality of said washers are supplied with
recirculated water, and a single washer is supplied with
substantially fresh water.
[0017] Advantageously, the method further comprises the step of
filtering said recirculated water prior to its supply to the or
each said washer.
[0018] Conveniently, the method further comprises the step of
passing said recirculated water over a weir prior to its supply to
the or each said washer.
[0019] Preferably, each said sample remains in each said washing
position for a predetermined washing period.
[0020] Advantageously, the method further comprises the step of RF
tagging each sample.
[0021] Conveniently, the method further comprises the step of
placing each said sample in a respective receptacle prior to said
conveying step.
[0022] Preferably, each said receptacle takes the form of a
sieve.
[0023] Advantageously, the method further comprises the step of
drying each said sample after it has been conveyed through all of
said washing positions and washed by the washers.
[0024] Conveniently, the method includes providing a plurality of
sequentially arranged discrete dryers and automatically conveying
said samples relative to said dryers so that each sample moves in
succession through or past said dryers for sequential drying by
each dryer.
[0025] Preferably, each said dryer comprises a heater arranged to
direct heat towards a respective drying position, and each sample
is automatically conveyed in succession through said drying
positions.
[0026] Advantageously, each said heater comprises an infra red
lamp.
[0027] Conveniently, each said sample remains in each said drying
position for a predetermined drying period.
[0028] Preferably, each said predetermined drying period is equal
in length to each said washing period.
[0029] Advantageously, the method further comprises the step of
automatically agitating each sample as it is dried.
[0030] Conveniently, the method further comprises the step of
photographing each sample after said drying step.
[0031] Preferably, the method further comprises the step of
weighing each sample after said drying step.
[0032] Advantageously, the method further comprises the step of
labelling each sample after said drying step.
[0033] According to another aspect of the present invention, there
is provided an apparatus for washing rock samples, the apparatus
comprising a plurality of sequentially arranged discrete washers,
each of which is spaced from a respective washing position and
configured to direct a washing flow of water towards said washing
position; and a conveyor operable to automatically convey a
plurality of discrete rock samples relative to said washers such
that each sample moves in succession through said washing positions
for sequential washing by each said washer.
[0034] Preferably, said plurality of washers comprise at least one
washer that is connected to a supply of substantially fresh water
so as to produce a washing flow of substantially fresh water.
[0035] Advantageously, said plurality of washers comprise at least
one washer that is connected to a recirculated flow of water.
[0036] Conveniently, the or each said washer that is supplied with
substantially fresh water is arranged sequentially after the or
each washer that is supplied with recirculated water.
[0037] Preferably, the apparatus comprises a plurality of washers
connected to said recirculated flow of water and a single washer
connected to said supply substantially fresh water.
[0038] Advantageously, the apparatus further comprises at least one
filter through which said recirculated flow of water passes.
[0039] Conveniently, the apparatus comprises a weir over which said
recirculated flow of water passes.
[0040] Preferably, the apparatus further comprises a pump operable
to pump said recirculating flow of water to said washers.
[0041] Advantageously, the apparatus further comprises a plurality
of sequentially arranged discrete dryers and a conveyor operable to
automatically convey said samples relative to said dryers such that
each sample moves in succession through or past said dryers for
sequential drying by each dryer.
[0042] Conveniently, each said dryer comprises a heater arranged to
direct heat towards a respective drying position, and said conveyor
is configured to move each sample in succession through said drying
positions.
[0043] Preferably, each said heater comprises an infra red
lamp.
[0044] Conveniently, the apparatus further comprises agitating
means operable to automatically agitate each sample as it is moved
through said drying positions.
[0045] Preferably, the apparatus further comprises a plurality of
receptacles, each receptacle being configured for the receipt of a
respective sample, and wherein said agitating means comprises a
mechanism operable to engage and oscillate said receptacles.
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] So that the invention may be more readily understood, and so
that further features thereof may be appreciated, embodiments of
the invention will now be described by way of example with
reference to the accompanying drawings in which:
[0047] FIG. 1 is a flow diagram illustrating the principal steps in
the method of the present invention;
[0048] FIG. 2 is a schematic illustration showing a general layout
of apparatus suitable for implementing the method steps of FIG.
1;
[0049] FIG. 3 is a schematic side elevational view of a sample
preparation module of the apparatus;
[0050] FIG. 4 is a schematic side elevational view of a sample feed
module of the apparatus;
[0051] FIG. 5 is a schematic side elevational view of a washing
module of the apparatus;
[0052] FIG. 6 is a schematic side elevational view of a first
drying module of the apparatus;
[0053] FIG. 7 is a schematic side elevational view of a second
drying module of the apparatus, and;
[0054] FIG. 8 is a schematic side elevational view of a recording
module of the apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0055] Turning now to consider the drawings in more detail, the
method of the present invention comprises a number of successive
stages or steps as illustrated schematically in FIG. 1, and which
will be described in more detail below with specific reference to
an embodiment of the apparatus. FIG. 2 shows a schematic
representation of individual modules of the apparatus which
correspond in their function to the stages or steps of the method
denoted in FIG. 1.
[0056] Initially, a plurality of discrete rock samples are prepared
for washing. This preparation stage of the method is illustrated
schematically at 1 in FIG. 1, and is performed with the use of a
preparation module 7 of the apparatus illustrated schematically in
FIG. 2. When the samples have been prepared ready for washing in
stage 1, they are arranged ready for washing in a feed stage of the
method denoted at 2 in FIG. 1 using a feed module 8 illustrated in
FIG. 2. The samples are then washed in a washing stage 3 of the
method which is carried out via the use of a washing module 9
illustrated schematically in FIG. 2. Two drying stages 4, 5 then
follow which are carried out via the use of respective drying
modules 10, 11. Finally, the washed and dried samples are then
recorded in a recording stage 6 of the method which is carried out
with the use of a recording module 12 of the apparatus. As
illustrated FIG. 1, the samples are processed through the
above-mentioned stages of the method in sequence.
[0057] FIG. 3 illustrates the preparation module 7 in more detail.
The module 7 comprises a work-surface 13 which is supported at a
convenient height above the ground by a plurality of legs 14 in the
manner of a conventional table. The legs 14 each have a castor 15
or other wheel arrangement at their lower ends so that the module
as a whole is moveable.
[0058] The work-surface 13 supports a computer 16 (which may take
the form of a conventional desktop, laptop or notebook computer)
having a memory, a display and an input keyboard. The computer 16
is operatively connected to an RFID reader 17 which is mounted to a
housing 18. The housing has an internal recess (not shown) which is
sized and configured to receive a support plate or the like which
are used in the method to support individual samples. One such
plate is illustrated schematically at 19 in FIG. 3. Each plate 19
carries a respective and individual RFID tag 20. The RFID reader
mounted on the housing 18 is positioned to scan or otherwise
identify the tags 20 of the plates as each plate is placed in or
moved through the housing 18.
[0059] The preparation module 7 also includes a tap or shower head
21 which is supported above the work-surface 13 and which is
connected to a supply of clean, and preferably warm water. A basin
22 is provided below the tap or shower head 21 and is supported
below the work-surface 13.
[0060] The preparation module 7 also supports a control unit 23
having a control panel 24 and which serves to control the various
functions of the modules of the apparatus. However, it is to be
appreciated that the control module 23 does not have to be provided
as part of the preparation module, and indeed could be mounted on
any of the other modules in the apparatus, or indeed even remotely
from the modules such as conveniently on a nearby wall.
[0061] The preparation stage 1 of the method involves initially
taking a rock sample obtained from a well and entering data
pertaining to the sample into the memory of the computer 16 via the
keyboard. Such data might include, for example; details of the
client or company whose well the sample was obtained from, the name
or identifying code of the particular well, the depth from which
the sample was taken, and details regarding the nature of the
actual sample itself (for example: ditch cuttings, core, sidewall
core, or field sample).
[0062] The sample itself is then crushed if necessary and soaked in
warm water from the tap or shower head 21 to soften any adhering
drilling mud. Detergent may be added to break down and remove any
oil residue.
[0063] The sample is then poured into a sieve 25 and the sieve is
placed on or engaged with a respective RF tagged support plate 19.
The support plate and the sieve are then positioned over the basin
22 to permit excess water remaining on the sample to drain into the
basin. As will be appreciated, the support plates 19 are thus each
configured to permit the flow of water from top to bottom and may,
for example, be generally annular in configuration and sized to
receive a sieve 25 therein.
[0064] The sieve 25 and its associated support plate 19 are then
pushed passed though the housing 18 and thus past the RFID reader
17 which identifies the tag 20 and passes that information to the
computer. The computer 16 then automatically associates the data
pertaining to the sample with the particular sieve 25 and sieve
plate 19. Alternatively, the housing 18 could be configured to
store a plurality of plates 19, for example in a stack, with its
RFID reader 17 positioned to scan or otherwise identify the tag 17
of each plate 19 as it is removed from the stack inside.
[0065] The sample, provided within its individual sieve 25 and
supported on a tagged plate 19 is then passed from the preparation
module 7 to the feed module 8 ready for the feed stage 2 of the
method.
[0066] The feed module 8 is illustrated in more detail in FIG. 4.
The module 8 comprises a conveyor housing 26 which is supported
above the ground by legs 27 on castors 28 in a similar manner to
the preparation module 7. The conveyor housing 26 houses a conveyor
mechanism comprising one or more conveyor belts or chains 29
arranged to run continuously around guide and/or drive sprockets 30
mounted for rotation relative to the housing 26. The conveyor
mechanism further includes a rotatable tensioning sprocket 31 which
is mounted for sliding movement in a vertical sense relative to the
housing 26 as denoted by arrow 32. The tensioning sprocket is
biased upwardly and the lower run of the or each belt or chain 29
engages and runs over the tensioning sprocket 32 in a manner known
per se.
[0067] The conveyor housing 26 is substantially open at its top, or
at least comprises one or more apertures such that the conveyor
chains or belts are exposed from above. Furthermore, the feed
module 8 is configured such that the upper run of the conveyor
belts or chains 29 is at least approximately level with the
work-surface 13 of the preceding preparation module. Also, as
illustrated in FIG. 2, the feed module 8 is positioned generally
adjacent the preparation module 7.
[0068] As indicated above, when each sample has been prepared in
accordance with the preparation stage 1 of the method it is passed
to the feed module 8. More particularly, a plurality of said
samples are prepared in succession, and each is passed to the feed
module such that the support plate 19 of each sample is placed on
the upper run of the conveyor chains or belts 29. FIG. 4
illustrates five such samples, in their respective sieves 25 and
supported on their respective plates 19 placed on the conveyor. As
illustrated, the sieves 25 and associated plates 19 are each
positioned in spaced relation to one another, to form a queue of
samples sitting on the conveyor 29. The sieves and support plates
are actually spaced from one another by a predetermined approximate
distance, as will be explained below.
[0069] Operation of the conveyor mechanism is controlled
automatically by the control unit 23 upon receipt of a start signal
from the control panel 24. The conveyor mechanism is operated under
the control of the control unit 23 to advance the conveyor 29 in a
step-wise manner. More particularly, the conveyor is operated to
move an index distance (denoted x in FIG. 4) over the sprockets 30
in the direction indicated in FIG. 4, and thus to move the samples
in their respective sieves 25 to the right (as illustrated) by an
equal amount. The conveyor then stops and remains stationary for a
predetermined dwell period, after which the conveyor then moves
again by a further, equal index distance. In a preferred
embodiment, the control unit 23 is configured to make each dwell
period approximately equal to one minute. However, it is proposed
to make the dwell period adjustable, for example via the control
unit 24, to enable an operator to set any convenient dwell
period.
[0070] As will thus be appreciated, the feed module 8 is operable
to feed the samples, in their respective sieves 25 and with their
associated support plates 19 towards the washing module 9 in
succession, and at predetermined time intervals from one
another.
[0071] The washing module 9 is illustrated in more detail in FIG.
5. The module comprises a conveyor housing 26 of substantially
identical form to the conveyor housing of the preceding feed module
8. The conveyor housing 26 is again supported above the ground by
legs 27 on castors 28, and houses a conveyor mechanism which is
also of substantially identical form to that of the feed module
8.
[0072] Above the conveyor housing 26, there is supported an array
of discrete washers 34. Each washer 34 preferably takes the form of
a shower head supported above the upper run of the conveyor and
configured to direct a washing flow of water 35, preferably
downwardly, towards a respective washing position 36 on the
conveyor 29. The washers 34 are arranged sequentially and a re
substantially equi-spaced from one another by a distance
substantially equal to the aforementioned index distance x.
[0073] The arrangement illustrated in FIG. 5 comprises five such
washers. The first four of the washers 34a, 34b, 34c, 34d, as
considered relative to the advance direction of the conveyor (left
to right in FIG. 5) are fluidly connected by appropriate pipework
37 to a supply of recirculated water, as will be described in more
detail below. However the final washer 34e in the sequence, (i.e.
the last washer as considered relative to the advance direction of
the conveyor 29) is fluidly connected to a supply of substantially
fresh water. In this context, fresh water is considered to
represent water which is substantially clean and free from
contaminants and which has not been used previously to wash any
rock samples in the method of the invention. In preferred
embodiments, the fresh water washer 34e is connected to a mains
supply of fresh water, the flow of which is controlled by a flow
control arrangement 38 which may comprise, for example, a flow
sensor, a timer and a solenoid-operated valve (not shown).
[0074] The washing module 9 further comprises a removable effluent
tank 39 which, in use, is positioned below the conveyor housing 26
to catch water and effluent falling downwardly from the washing
positions 36. The effluent tank is mounted for movement on castors
40 and is received between the legs 27 supporting the conveyor
housing 26. Approximately halfway along the length of the tank 39,
there is provided an internal weir 41, which extends vertically
upwardly from the base of the tank and which terminates at a
position generally below the tensioning sprocket 31 of the conveyor
mechanism when the tank is installed in its in-use position
illustrated in FIG. 5. The weir 41 thus effectively divides the
tank into two chambers; a first chamber 42 located to the left in
FIG. 5, and a second chamber 43 located to the right in FIG. 5.
[0075] The first chamber 42 is open at the top, but the second
chamber 43 is closed by a cover 44. A filter 46, preferably formed
of foam, extends across the top of the second chamber 43 just below
the level of the top of the weir 41. The second chamber 43 also has
a fluid outlet 47 at its end remote from the first chamber 42.
[0076] Operation of the washing module 9 is controlled by the
control unit 23. More particularly, the conveyor mechanism of the
washing module is operated to advance the conveyor 29 in a
step-wise manner in synchronism with the conveyor of the preceding
feed module 8. The conveyor of the washing module 9 is thus also
moved by index distances x between successive dwell periods. Thus,
in the preferred operating regime the conveyor 29 is advanced so as
to move each discrete rock sample, in turn, through each of the
washing positions 36 under the respective washers 34, and to
position each sample under a successive washer during each dwell
period (preferably one minute). As will thus be appreciated, when
the samples, in their respective sieves 25, are positioned beneath
the washers, the flow of washing water downwardly from the washers
serves to wash the samples. The washers can be operated in
synchronism with the conveyor so as only to permit the flow of
washing water 35 when the conveyor is stationary with the samples
located in washing positions beneath respective washers 34. However
this is not essential, and indeed the system could instead be
operated with substantially continuous flow of water through the
washers 34.
[0077] As each sample advances through the washing module, it is
washed, in turn, by the water flowing from each washer 34. As will
be appreciated, the most effluent is thus produced from the first
washer 34a in the sequence, and the samples each become gradually
cleaner as they move though the module.
[0078] The excess water and effluent washed from the samples by the
first and second washers 34a, 34b falls vertically downwardly
directly into the first chamber 42 of the effluent tank, to the
left of the weir, where solid constituents of the effluent builds
up as a deposit 48. The water and effluent produced from the
samples as they are washed by the subsequent washers 34c, 34d, 34e,
is blocked from falling into the second chamber by the cover 44 and
so is also directed into the first chamber 42. As will be
appreciated, the weir 41 maintains a constant water level 49 in the
first chamber and permits the flow of excess water over the weir,
and into the second chamber 43. This water flowing over the weir 41
passes through the filter 46 and is thus filtered. The water
flowing into the second chamber then flows out through the fluid
outlet 47.
[0079] Because the effluent tank is mounted on casters 40 it can be
conveniently rolled out from its in-use position beneath the
conveyor housing 26 for periodic emptying of deposit 48 and
cleaning of the filter 46.
[0080] After being washed by each washer 34, each sample is then
transferred by the conveyor 29 to the first drying module 10 which,
as illustrated in FIG. 2, is positioned immediately adjacent the
washing module 9 as the next module in the sequence.
[0081] The first drying module 10 is illustrated in more detail in
FIG. 5. The module comprises a conveyor housing 26 of substantially
identical form to the conveyor housing of the preceding washing
module 9 and the feed module 8. The conveyor housing 26 is again
supported above the ground by legs 27 on castors 28, and houses a
substantially identical conveyor mechanism.
[0082] Above the conveyor housing 26, there is supported an array
of discrete dryers 49. Each washer 49 preferably takes the form of
an infra-red lamp supported above the upper run of the conveyor and
configured to radiate heat downwardly towards a respective drying
position 50 on the conveyor 29. The dryers 49 are arranged
sequentially and are substantially equi-spaced from one another by
a distance substantially equal to the aforementioned index distance
x.
[0083] The first drying module additionally comprises a mechanism
for agitating rock samples, in their respective sieves 25, as they
are advanced through the module by the conveyor 29. The agitation
mechanism can take any convenient form and may comprise, for
example, one or more agitating bars 51 arranged immediately below
the upper run of the conveyor 29 and arranged to engage the
supporting plates 19 associated with the samples as they move
through the module. The or each agitating bar is mounted for
oscillating movement, for example under the action of an offset cam
mechanism (not shown).
[0084] Additionally, the conveyor housing 26 of the first drying
module 10 is provided with one or more extraction ports 52 for
fluid connection to an extractor fan to pull a flow of drying air
across or over the drying positions 50.
[0085] The first drying module 10 further comprises a removable
filtration tank 53 which, in use, is conveniently positioned below
the conveyor housing 26. The filtration tank 53 is similar in form
to the effluent tank 39 of the preceding washing module 9 and so is
again mounted for movement on castors 40 and is received between
the legs 27 supporting the conveyor housing 26. The filtration tank
53 again includes an internal weir 54 which divides the tank into
two chambers; a first chamber 55 located to the left in FIG. 6, and
a second chamber 56 located to the right in FIG. 6. However, in
this arrangement, both chambers closed across the top by a cover
57, and each chamber has a respective filter 58a,b extending below
the level of the top of the weir 54. In this module, the first
chamber 55 of the tank has a fluid inlet 59. The fluid inlet 59 is
fluidly connected to the fluid outlet 47 of the preceding washing
module, and is thus arranged to receive a flow of water directed
into the chamber 55 from the chamber 43 of the washing module 9.
The second chamber 56 of the first drying module 10 has a fluid
outlet 60 of substantially identical form to the fluid outlet 47 of
the preceding washing module 9.
[0086] Operation of the first drying module 10 is controlled by the
control unit 23. More particularly, the conveyor mechanism of the
drying module is operated to advance the conveyor 29 in a step-wise
manner in synchronism with the conveyors of the preceding washing
module 9 and the feed module 8. The conveyor of the drying module
10 is thus also moved by index distances x between successive dwell
periods. Thus, in the preferred operating regime the conveyor 29 is
advanced so as to move each discrete rock sample, in turn, through
each of the drying positions 50 under the respective dryers 49, and
to position each sample under a successive dryer during each dwell
period (preferably one minute). As will thus be appreciated, when
the samples, in their respective sieves 25, are positioned beneath
the dryers the heat radiated downwardly from the dryers serves to
dry the samples. Additionally, operation of the extractor fan (not
shown) connected to the extraction ports 52 pulls a flow of drying
air over the samples, and the agitation bars 51 serve to oscillate
the sieves 25 and thus shake excess water from the samples therein.
The dryers, agitator bars 51 and the extractor fan can all be
operated in synchronism with the conveyor so as only to be
energised when the conveyor is stationary with the samples located
in drying positions 50 beneath respective dryers 49. However this
is not essential, and indeed the system could instead be operated
with substantially continuous energisation of the dryers 49, the
agitation mechanism and the extractor fan.
[0087] As each sample advances through the drying module 10 it is
dried, in turn, by the heat produced by each dryer 49.
[0088] The filtration tank 53 does not receive any water dried from
the rock samples above. Instead, the filtration tank 53 simply
serves to further filter, and hence cleanse, the water which was
captured by the effluent tank 39 of the preceding module. As will
be appreciated, the weir 54 maintains a constant water level in the
first chamber 55, above the level of its filter 58a and permits the
flow of excess water over the weir, and into the second chamber 56
through its filter 58b. The water thus flows through the filtration
tank 53 from the preceding effluent tank 39, by passing upwardly
through the first filter 58a, over the weir, and then passing
downwardly through the second filter 58b. The water flowing into
the second chamber then flows out through the fluid outlet 60.
[0089] Because the filtration tank is mounted on casters it can be
conveniently rolled out from its in-use position beneath the
conveyor housing 26 for periodic emptying of any build up of silt
and for cleaning of the filter 46.
[0090] After being dried by each dryer, each sample is then
transferred by the conveyor 29 to the second drying module 11
which, as illustrated in FIG. 2, is positioned immediately adjacent
the first drying module 10 as the next module in the sequence.
[0091] The second drying module 11 is illustrated in more detail in
FIG. 7, and as will be seen is substantially identical to the first
drying module 10. The same reference numerals are thus used in FIG.
7 to denote identical or corresponding component parts of the
second drying module 11. Operation of the second drying module 11
is also substantially identical to the manner in which the first
drying module 10 is operated.
[0092] More particularly, the conveyor mechanism of the second
drying module 11 is operated to advance the conveyor 29 in a
step-wise manner in synchronism with the conveyors of the preceding
first drying module 10, the washing module 9 and the feed module 8.
The conveyor of the second drying module 11 is thus also moved by
index distances x between successive dwell periods. Thus, in the
preferred operating regime the conveyor 29 is advanced so as to
move each discrete rock sample, in turn, through each of the drying
positions 50 under the respective dryers 49, and to position each
sample under a successive dryer during each dwell period
(preferably one minute) in exactly the same manner as in the case
of the preceding first drying module 10. As will thus be
appreciated, when the samples, in their respective sieves 25, are
positioned beneath the dryers the heat radiated downwardly from the
dryers serves to dry the samples. Additionally, operation of the
extractor fan (not shown) connected to the extraction ports 52
pulls a flow of drying air over the samples, and the agitation bars
51 serve to oscillate the sieves 25 and thus shake excess water
from the samples therein. The dryers, agitator bars 51 and the
extractor fan can all be operated in synchronism with the conveyor
so as only to be energised when the conveyor is stationary with the
samples located in drying positions 50 beneath respective dryers
49. However this is not essential, and indeed the system could
instead be operated with substantially continuous energisation of
the dryers 49, the agitation mechanism and the extractor fan.
[0093] As each sample advances through the second drying module 11
it is dried, in turn, by the heat produced by each dryer 49. After
passing through both drying modules in this manner, each sample
will thus have been dried by a total of 10 discrete dryers 49 in
succession.
[0094] It is significant to note that the fluid inlet 59 of the
filtration tank 53 of the second drying module 11 is fluidly
connected to the fluid outlet 60 of the filtration tank of the
first drying module 10. Furthermore, in the case of the second
drying module 11, the second chamber 56 of the filtration tank 53
does not have a fluid outlet in the same way that the filtration
tank of the preceding first drying module 10 does. Instead, the
second drying module 11 comprises a pump 61 which is arranged and
operable to pump water out of the second chamber 56. Preferably, as
illustrated in FIG. 11, the pump 61 takes the form of an immersion
pump provided at the bottom of the second chamber 56.
[0095] As illustrated most clearly in FIG. 2, the pump 61 is
fluidly connected via the pipework 37 to the first four washers
34a, 34b, 34c, 34d of the washing module 9. The pump 61 is thus
operable to pump water from the second chamber 56 of the filtration
tank 53 in the second drying module, in a recirculating manner back
to the washers 34a-d of the washer module 9 and thus drives the
flow of recirculated water to those washers. As already explained
above, the fifth washer 34e of the washing module 9 is supplied
with a flow of substantially fresh water, for example from a mains
supply. As will thus be appreciated, the supply of fresh water to
the fifth washer 34e in the sequence represents the sole input of
fresh water into the system. The other four washers 34a-d are all
supplied with water which has already been used to wash rock
samples and which has been filtered and recycled via the effluent
tank 39 and the two filtration tanks 53.
[0096] After being dried by each dryer 49 of the second drying
module 11, each sample is then transferred by the conveyor 29 to
the recording module 12 which, as illustrated in FIG. 2, is
positioned immediately adjacent the second drying module 11 as the
next module in the sequence.
[0097] FIG. 8 illustrates the recording module 12 in more detail.
The module 12 comprises a work-surface 62 which is supported at a
convenient height above the ground by a plurality of legs 63 in the
manner of a conventional table. The legs 63 each have a castor 64
or other wheel arrangement at their lower ends so that the module
as a whole is moveable in the same manner as each of the preceding
modules. The legs 63 support the work surface 62 above the ground
at a height substantially level with the conveyor of the preceding
drying module 11. The conveyor thus serves to pass each sample, in
its respective sieve and on its respective support plate, on to the
work-surface 62 of the recording module 12.
[0098] The work-surface 62 supports a housing 65 which is
positioned immediately adjacent the preceding drying module 11 (to
the left as viewed in FIG. 8). The housing has an internal recess
(not shown) of similar configuration to the recess provided in the
housing 17 of the preparation module 7. The recess is thus sized
and configured to receive the support plates 19 of each sample as
they are passed to the recording module automatically from the
second drying module 11. The housing 65 has a second RFID reader 66
located at its end remote from the preceding drying module 11.
[0099] The recording module 12 further comprises a camera 67 which
is mounted in a position spaced above the housing 65 by a camera
support 68. The camera 67 is oriented in a manner effective to
capture images of samples passing below the camera. The camera can
take any convenient form. For example, in one embodiment the camera
67 may take the form of a digital single-lens-reflex camera having
a close-up (macro) lens 69 fitted with a ring-flash 70. The camera
67 is mounted such that its lens 69 points generally downwardly,
and preferably vertically downwardly towards the work-surface 62.
Alternatively, the camera could take the form of a 3D camera, and
may thus be stereoscopic. The camera is operatively connected to a
second computer 71 (which may take the form of a conventional
desktop, laptop or notebook computer) having a memory, a display
and an input keyboard. The second RFID reader 66 is also
operatively connected to the computer 71. The computer 71 on the
recording module 12 is operatively connected, for example by a
suitable network, to the computer 16 of the preparation module
7.
[0100] The recording module 12 also includes a tap or shower head
72 which is supported above the work-surface 62 and which is
connected to a supply of clean, and preferably warm water. A basin
73 is provided below the tap or shower head 72 and is supported
below the work-surface 62.
[0101] The recording stage 6 of the method is performed as follows
using the recording module 12. Washed and dried samples are
automatically advanced, via the conveyor 29 of the preceding drying
module 11, into the recessed housing 25, ready for inspection by an
operator or technician. It is possible that during the preceding
washing and drying stages some samples may have become scattered
around their respective sieves and so the operator or technician is
afforded an opportunity manually to arrange the constituent grains
into the centre of the sieve ready for photography.
[0102] The sieve 25 containing the sample can then be slid, along
with its underlying support plate 19, beneath the camera 67. In
this position, the RF tag 20 on the support plate 19 becomes
aligned with the second RFID reader 66 which identifies the tag and
passes that information to the computer 67. The computer then calls
up the data pertaining to the sample recorded in the preparation
module computer 16 associated with the scanned RF tag 20.
[0103] After identification of the sample under the camera 67 by
the RFID reader 66 and the logging of that information in the
memory of the computer 71, a predetermined period of time elapses
(for example 5 seconds) to permit any last minute rearrangement of
the sample in the sieve by the operator or technician, and then the
camera 67, being controlled automatically by the computer 71,
captures an image of the sample in the sieve 25. The image is then
automatically associated in the memory of the computer 71 with the
data pertaining to the sample for storage and later viewing and
analysis of the sample.
[0104] A weighing device (not shown), for example in the form of
digital scales, may be provided on the recording module for
weighing each sample, and is preferably connected to the computer
71. The weight of each sample is thus automatically recorded and
logged by the computer and associated with the respective sample. A
printer (not shown) may also be connected to the computer 71 for
control by the computer so as to print a label displaying the
relevant sample data. The sample can then be poured from the sieve
25 into a sample storage bag or the like, and the label affixed to
the bag to identify its contents. The empty sieve (and indeed the
supporting plate 19 if necessary) can then be rinsed clean of any
remaining sample using the shower head 72 and basin, before being
returned to the preparation module for reuse with another rock
sample.
[0105] It is proposed that the operation and control of the entire
method and apparatus of the present invention will be handled by
bespoke software. The software will be configured to control each
of the aforementioned modules, and also to automatically
photograph, weigh, and label each sample which is processed by the
system.
[0106] The above-described method and apparatus of the present
invention provide a very efficient and effective way to wash, dry
and log a large number of rock samples in a quick, reliable and
cost-effective manner. Also, because the apparatus of the preferred
embodiment uses multiple washers 34a-d which are supplied with
recycled water previously used for washing samples, the system has
a very low water-consumption. This makes the system of the present
invention highly advantageous from an environmental point of
view.
[0107] The enhanced speed and efficiency of the sample cleaning
process, in turn, improves the speed and efficiency of the
decision-making process for the oil & gas companies, during
very costly field operations.
[0108] As well as improvements in the speed, efficiency and
environmental considerations of the sample washing process, the
method of the present invention also allows for improvements in
sample labelling and initial sample data capture on-line, such as
sample weighing, sample photography and preliminary geotechnical
analysis, e.g. XRF analysis.
[0109] Whilst the invention has been described above in detail,
with specific reference to particular embodiments of the method and
apparatus of the invention, it is to be appreciated that various
modifications can be made either to the method or to the apparatus
without departing from the scope of the invention. For example,
whilst the embodiments described in detail above involve the
provision and use of support plates 19 to support and carry the
individual sieves 25, it is envisaged that in variants of the
invention the support plates may not be necessary. For example, it
is proposed that the conveyors 29 could each be configured so as to
have a plurality of predefined recesses or other formations to
receive respective sieves. In such an arrangement either the sieves
themselves, or even the conveyor, could carry the RF tags 20 used
to identify each sample as it progresses through the apparatus. In
the event that the RF tags are mounted to the conveyor, it is
envisaged that each tag would be mounted adjacent a respective
sieve-receiving recess or the like.
[0110] Furthermore, whilst the invention has been described above
with reference to an arrangement comprising two successive drying
modules 10, 11, it is proposed variants could use on a single
drying module. Indeed, it may be convenient for some applications
to integrate the aforementioned modules into a single unit. For
example, it is proposed that the entire system of the invention
could be made so as to be sufficiently compact to fit inside a
standard shipping container for convenient transportation. In this
manner it is proposed to make the system mobile so that it can be
conveniently moved from one site to another, and even for use on
offshore drilling rigs.
[0111] In variants of the invention it is possible to replace the
plurality of discrete and spaced apart dryers with a single,
substantially continuous dryer. For example, an elongate oven or
drying lamp could be provided through or under which the washed
samples are conveyed during the drying stage of the method.
[0112] Whilst the invention has been described with reference to an
arrangement in which the tanks 39, 53 are each mounted on wheels or
casters so as to be removable from their respective modules, it is
envisaged that they could instead be formed as integral parts of
each module.
[0113] When used in this specification and claims, the terms
"comprises" and "comprising" and variations thereof mean that the
specified features, steps or integers are included. The terms are
not to be interpreted to exclude the presence of other features,
steps or integers.
[0114] The features disclosed in the foregoing description, or in
the following claims, or in the accompanying drawings, expressed in
their specific forms or in terms of a means for performing the
disclosed function, or a method or process for obtaining the
disclosed results, as appropriate, may, separately, or in any
combination of such features, be utilised for realising the
invention in diverse forms thereof.
[0115] While the invention has been described in conjunction with
the exemplary embodiments described above, many equivalent
modifications and variations will be apparent to those skilled in
the art when given this disclosure. Accordingly, the exemplary
embodiments of the invention set forth above are considered to be
illustrative and not limiting. Various changes to the described
embodiments may be made without departing from the spirit and scope
of the invention.
* * * * *