GB2574055A

GB2574055A - Industrial dust filter system

Info

Publication number: GB2574055A
Application number: GB1808613.2A
Authority: GB
Inventors: Phillip Wray Andrew; Robert Astle Lee
Original assignee: Environmental Dust Monitor Systems Ltd
Current assignee: Environmental Dust Monitor Systems Ltd
Priority date: 2018-05-24
Filing date: 2018-05-25
Publication date: 2019-11-27
Also published as: GB201808579D0; GB201808613D0

Abstract

An industrial dust filter comprises an enclosure (1) in which is mounted a filtration element (4) into which dust-laden air passes from a first chamber at a first side of the element and from which filtered air emerges into a second chamber on a second side of the element. The enclosure (1) carries a differential pressure sensor (5) connected to the first and second chambers, the sensor outputting a signal representing the difference in pressure between the two chambers. A controller (8) is provided for receiving the signal and for transmitting data wirelessly representing the signal to a remote monitoring station configured to generate an alarm when the pressure differential is above a pre-determined level. The industrial dust filter allows centralised control of replacement filter elements, avoiding the risk of failure of the filtering function. A plurality of filters in different locations can be monitored simultaneously and alerts generated to instruct replacement of a specific filter element when required.

Description

INDUSTRIAL DUST FILTER SYSTEM

Field of the Invention

This invention relates to industrial dust extraction systems and in particular to filtration units for such systems.

Background to the Invention

Industrial dust filters can be provided with an analogue gauge to indicate the differential pressure between the clean side of the filter unit (the clean filtered air section) and the dirty side of the filter unit (where dust laden air enters the dust filter unit). This differential reading is an indication of how dirty or blinded the dust filter media is. In essence the differential pressure reading is an indication of how hard it is for the dust laden air to pass through the filter media, leaving behind the dusts collected on the surface of the filter media, and allowing the clean air into the clean side of a dust filter unit.

If the dust filter unit is not checked regularly for correct operation and/or performance or maintenance, the dust filter’s media could become blinded and blocked. Blockages lead to poor extraction and could lead to increases in dust exposure for workers as the extraction performance diminishes, due to diminished air flows. Slower ductwork velocities can result in dust settlement in ductwork. For dense dusts, this extra weight in ductwork can collapse the ductwork from its fixings, potentially causing injury to workers and/or damage to property. Also, for dusts that are potentially explosive in a dust cloud, should an explosion occur inside the dust filter unit and these dusts have settled out in the ductwork, there is a risk of the explosion or shock wave lifting the dusts settled out in the ductwork, causing the explosion to travel back along the ductwork and into the work areas. This secondary explosion can be catastrophic. So managing extraction air flows and filter media differential pressures are critically important functions.

Analogue differential gauges are often used to establish the differential pressures. However, in many instances this visual check is neither completed nor understood.

- 2 Summary of the Invention

According to the invention there is provided an industrial dust filter comprising an enclosure in which is mounted a filtration element into which dustladen air passes from a first chamber at a first side of the element and from which filtered air emerges into a second chamber on a second side of the element, the enclosure carrying a differential pressure sensor connected to the first and second chambers, the sensor outputting a signal representing the difference in pressure between the two chambers, and a controller for receiving the signal and for transmitting wirelessly data representing the signal to a remote monitoring station configured to generate an alarm when the pressure differential is above a pre-determined level.

The controller may receive a voltage signal from the pressure sensor and may be configured to digitise the signal and convert the digitised signal to represent a pressure differential value. The controller may include a GSM transmitter to transmit the data to a remote webserver.

In an alternative embodiment, the controller may include a wi-fi or similar wireless communications device for communicating with a local area network or the like to enable communication through the internet with a central monitoring station, for example the webserver previously mentioned.

The sensor and controller may be mounted within the enclosure, but will typically be mounted externally thereof. The controller may be linked to display means to provide a locally-visible indication of the state of the filter to allow an operator to make a quick visual check. This may be numerical or a graphical representation.

The industrial dust filter of the invention is capable of being monitored remotely, allowing centralised control of the replacement of filter elements in a timely fashion, avoiding the risk of failure of the filtering function. A plurality of filters in different locations can thus be monitored simultaneously and alerts generated to instruct replacement of a specific filter element when required. It will also be possible to advise on seasonal trends in the differential pressure and on worker/operator abuse of the filtration equipment.

-3Brief Description of the Drawings

In the drawings, which illustrate an exemplary embodiment of the invention:

Figure 1 is a diagrammatic view of the dust filter; and

Figure 2 is a diagram of the controller in the filter of Figure 1.

Detailed Description of the Illustrated Embodiment

In the simplified diagrammatic view shown in Figure 1, the dust filter comprises an enclosure 1 with an inlet 2 on one side for dust-laden air extracted from a building, and an outlet 3 on the other side for discharge of filtered air. Between the inlet 2 and the outlet 3 is mounted a replaceable filter element 4. Because the filter element 4 gradually becomes clogged by dust, its resistance to flow of air increases with time, resulting in an increasing pressure differential between the two sides of the element. Typically, the outlet is connected to suction means - a centrifugal fan, for example - and so will be the lower pressure side.

A microelectromechanical pressure sensor 5, suitably a MPX5010DP device manufactured by NXP, has a pair of pneumatic inputs which are connected by flexible hoses 6 and 7 to the enclosure 1 on opposed sides of the filter element 4. The sensor 5 produces an analogue voltage output proportional to the pressure differential between the two inputs, the voltage output being connected to a processor unit 8.

As may be seen from Figure 2, the processor unit 8 comprises a microprocessor module 9, a low-voltage (e.g. 12V DC) switched mode power supply 10, connected in turn to the mains power supply (e.g. 240V AC) of the dust filter, and a GSM unit 11 which will include a suitable SIM Card. The microprocessor module 9 could be in the form of a standard programmable microcontroller board such as the Arduino Uno, but it will be appreciated that, while the device is shown as comprising discrete components, it can readily be configured as a single dedicated microcircuit device.

The microprocessor 9 receives the analogue voltage signal from the pressure sensor 5 and converts it into a digital value via an analogue to digital converter stage. Typically, the microprocessor will be configured to perform this

-4operation at regular predetermined time intervals, for example 30 minutes. The digital value is then transmitted by the GSM device via antenna 12 (which may be integral with the GSM device) to a remote webserver, along with an identifier for the particular filter, enabling the webserver to monitor the operation of a 5 number of filters which can be at widely-spaced locations. The webserver is configured to compare the value of the received pressure differential with a predetermined threshold value and to generate an alert if the received value exceeds the threshold. This alert can be transmitted to maintenance staff, for example, to instruct the replacement of the filter element. The status of each filter 10 installation can also be displayed on a website to enable monitoring by the maintenance staff, for example. The webserver can be configure with a preliminary threshold pressure differential for a particular filter installation, so that when this threshold is exceeded, the ordering of a replacement is initiated before a second threshold is exceeded, indicating that immediate replacement of 15 the filter is required.

Claims

1. An industrial dust filter comprising an enclosure in which is mounted a filtration element into which dust-laden air passes from a first chamber at a first side of the element and from which filtered air emerges into a second chamber on a second side of the element, the enclosure carrying a differential pressure sensor connected to the first and second chambers, the sensor outputting a signal representing the difference in pressure between the two chambers, and a controller for receiving the signal and for transmitting wirelessly data representing the signal to a remote monitoring station configured to generate an alarm when the pressure differential is above a pre-determined level.

2. An industrial dust filter according to Claim 1, wherein the controller is configured to receive a voltage signal from the pressure sensor and to digitise the signal and convert the digitised signal to represent a pressure differential value.

3. An industrial dust filter according to Claim 1 or 2, wherein the controller includes a GSM transmitter to transmit the data to a remote webserver.

4. An industrial dust filter according to Claim 1, 2 or 3, wherein the sensor and controller are mounted externally of the enclosure.

5. An industrial dust filter monitoring system, comprising a plurality of dust filters according to any preceding claim in communication with a central monitoring station configured to store a pre-determined pressure differential for each of said filters, to receive data from all of said filters and to generate an alarm in relation to any of filters where the received pressure differential exceeds the stored pre-determined level.

6. A system according to Claim 5, wherein the monitoring station is configured to transmit the alarm to a maintenance facility to request replacement of the filter element concerned.