GB2228215A

GB2228215A - Materials handling system including separation and measurement stages

Info

Publication number: GB2228215A
Application number: GB8929053A
Authority: GB
Inventors: James Hinshelwood Fairley Daly; Philip Taylor; Maurice Allan
Original assignee: Data Acquisition & Technical A
Current assignee: Data Acquisition & Technical A
Priority date: 1989-01-07
Filing date: 1989-12-22
Publication date: 1990-08-22
Also published as: GB8900338D0; GB8929053D0

Abstract

A materials handling system (10) receives material for an in-flow pipe (11) which delivers into a distribution box (17). Box (17) delivers to a fraction separator (12) from which a first fraction is collected by device (13) and a second fraction is collected by device (14). A sensor (20) associated with device (14) provides a weight measure of the second fraction to a control unit (22). The system is particularly applied to the material discharged from down-hole drilling operations. The separator (12) includes a sieve mesh (16) which retains larger solids which move over its surface to be collected in the receptacle (14) where the sensor (20) measures weight. When a predetermined weight has been collected, the control unit (22) causes the receptacle (14) to discharge. Fines and liquid passing through the mesh (16) are collected in the receptacle (13), where a measure of flowrate may be made by a sensor (26). Density of the inflow, and vibratory state of the sieve mesh (16) are also measured and supplied to the control unit (22). Assessment of the nature and quantity of the various discharges is made. <IMAGE>

Description

A MATERIALS HANDLING SYSTEM This invention relates to a materials handling system particularly for use with discharges from down-hole drilling operations.

In down-hole drilling operations there are various requirements for monitoring and measuring the discharge of material for example to assess the efficiency of the cutting or drilling operations or to assess the quantity of drilling fluids being discharged and which may be of a toxic nature so that their environmental effect may be assessed.

According to the present invention there is provided a materials handling system comprising means for delivering material to be monitored, fraction separation means for separating material received from said delivery means into first and second fractions, first and second collection means for collecting the respective separated fractions, and means for measuring at least one of said collected fractions.

Preferably said measuring means comprises a receptacle of limited volume which is arranged intermittently to be filled and emptied, first sensor means being provided to sense when the receptacle is filled and being arranged to energise means for emptying the receptacle.

Preferably second sensor means are associated with said delivery means to sense the rate of delivery of material.

Preferably a third sensor means is arranged to measure the other collected fraction, for example flow rate.

Preferably a data handling device is connected to said sensor means and arranged to store data emanating from said sensor means and to interpolate the data from the first sensor means to provide a measure of said one collected fraction when said receptacle is being emptied.

Embodiments of the present invention will now be described by way of example with reference to the accompanying drawing, in which Fig.l illustrates a first embodiment; and Fig 2. illustrates a second embodiment.

A materials handling system 10 in accordance with the present invention, illustrated in Fig. 1, comprises an in-flow pipe 11 for delivering materials to be monitored, to a distribution box 17, a fraction separator 12 for separating material received from box 17 into first and second fractions, a first collection device 13 associated with separator 12 and a second collection device 14 also associated with separator 12. Device 14 is in the form of a receptacle of predetermined limited volume and in this embodiment has a movable base plate 15 so that when the receptacle becomes filled with a collected fraction the base plate 15 can be moved to a position which allows the receptacle to be emptied prior to the base plate 15 being returned to close the bottom of the receiptacle to continue with collection of the relevant separated fraction.

The separator 12 is conveniently in the form of a vibratory device having a mesh like platform 16 connected to a vibratory drive so that material delivered through pipe 11 and which may be a mixture of solids and fluids is delivered over the upper surface of platform 16 as indicated by arrows 18 and fine particulates and fluids pass through the mesh like platform 16 to be collected by collecting device 13 whereas larger size particulates are moved over the surface of platform 16 to emerge from the end thereof and be collected by receptacle 14.

A first sensor 20 is associated with the receptacle 14, conveniently being in the form of four load cells, and this sensor provides a measure of the separated fraction collected by the receptacle 14 in that it monitors the weight of the collected fraction and delivers a weight indicating signal to a control unit 22 which when the measured weight reaches a preset value issues a control signal along line 23 to a hydraulic drive unit 24 which actuates hydraulic rams 25a, 25b to move the base plate 15 and thereby open the receptacle for a preset time period sufficient to enable the collected fraction to be discharged. Unit 24 thereafter reactivates rams 25a, 25b to close the receptacle and this cycle of operations is repeated on a continuous basis.

A second sensor 21 is associated with the in-flow pipe 11 to provide a measure of the density of the materials delivered by pipe 11, this measure being delivered to the control unit 22. A third sensor 26 is associated with the outlet 13A of the collection device 13 to provide a measure for example flow rate of the fraction collected therein and this sensor also provides its signal to control unit 22. A monitoring sensor 27 is associated with the separator 12 to determine whether or not the platform 16 is in vibratory motion and this signal is likewise delivered to the control unit 22.

The control unit 22 is arranged to receive the various signals from the sensors and in addition to checking for potential errors in the sensory signals is arranged to process these to obtain an accurate reading of the current weight of material in the receptacle 14 during the time interval that the receptacle is being filled and to interpolate between such readings to obtain a measure of the separated fraction delivered to receptacle 14 during the time interval that the receptacle is being emptied so that on a cyclic basis the total weight of the separated fraction delivered to the receptacle 14 is measured.Each of these measures is stored in the control unit 22 either by microprocessor memory or by paper chart and by computation from the signals delivered by sensors 21, 26 and the duration of the cyclic operation of receptacle 14,an assessment can be made of the quantity of fluid or fine particulates discharged through receptacle 14 to the environment.

In the system 10 which is intended for use with discharges from down-hole drilling operations it is preferred that the control unit 22 is located in an nonhazardous zone 30 relatively remotely from the remaining components of the system 10 which are likely to be located in an hazardous zone 31. Rams 25a, 25b may be operated either hydraulically or pneumatically and the base plate 15 is a preferred device for emptying the receptacle 14 but the receptacle 14 could be mounted for rotation to permit emptying thereof. Likewise separator 12 need not be of a vibratory type.

The sensory arrangement 20 which has been described is weight based but may alternatively involve the displacement of water from the receptacle 14 to enable the volume of the collected fraction to be measured. In this case the control unit 22 is arranged not only to initiate the empty or dump cycle but also to control an in-flow of a measured quantity of water at the commencement of the subsequent collection cycle.

It will be appreciated that the control unit 22 is computer or microprocessor based and is arranged to monitor malfunction of the system 10 and to operate malfunction alarms. The control unit 22, during the emptying cycle may initiate operation of a spray system to clean the interior of receptacle 14 so that unwanted retention of the collected fraction is avoided from one fill cycle to another.

Fig 2. illustrates another form of the device 14 which operates by impulse monitoring. In this arrangement the output from platform 16 (or possibly directly from distribution box 17) is delivered to a screen plate 32 set at a predetermined height above an inclined measurement plate 33 mounted on a load block 34 carrying a micro cell strain sensor 20. Plate 32 causes discharged particles to impinge on the plate 33 with a momentum calibrated essentially according to particle size and hence weight. The particles are sent to dump through shute 35 whilst the weight is sensed by sensor 20 and sent to the control unit 22 via zener barrier 36. In this arrangement no dump cycle initiation is required for device 14 and the unit 22 is connected via line 37 to a remote computer (not shown). Conveniently unit 22 incorporates a type 1730 flow display 38.

Claims

1. A materials handling system comprising means for delivering material to be monitored, fraction separation means for separating material received from said delivery means into first and second fractions, first and second collection means for collecting the respective separated fractions, and means for measuring at least one of said collected fractions.

2. A system as claimed in claim 1, wherein said measuring means comprises a receptacle of limited volume which is arranged intermittently to be filled and emptied, first sensor means being provided to sense when the receptacle is filled and being arranged to energise means for emptying the receptacle.

3. A system as claimed in either preceding claim, wherein a data handling device is connected to said sensor means and arranged to store data emanating from said sensor means and to interpolate the data from the first sensor means to provide a measure of said one collected fraction when said receptacle is being emptied.

4. A materials handling system substantially as hereinbefore described with reference to Fig. 1 of the accompanying drawing.

5. A materials handling system substantially as hereinbefore described with reference to Fig.2 of the accompanying drawing.