ENVEA have been at the forefront of environmental monitoring and process control over four decades and with the emergence of the industrial internet of things (Industry 4.0) ENVEA are yet again providing innovative solutions which harness the potential of this new industrial era.

In this series of articles, we will be exploring the relationship between industrialisation and particulates alongside the emergence of particulate abatement, monitoring and regulation through each of the four industrial eras.

In this first article we will be examining Industry 1.0 in relation to particulates and how advancements in this era influence modern day power generation and manufacturing.

Industry 1.0

Industry 1.0 (1760-1840) is considered to be the first industrial revolution with the transition to steam and water powered machinery in manufacturing, transforming industries such as agriculture, textiles and mining. The efficiencies made within the steam engine design enabled its use in manufacturing processes (such as Iron production) and developments in rail and shipping saw the expansion
of trade and increased manufacturing output. During this period coal burning became widespread.

Particulates during Industry 1.0

Although combustion processes were not yet able to be used as a source for power generation as today, the increased use of coal in industry had a significant impact on pollution levels. There was little understanding of the existence of fine particles and the associated health implications and little regulations controlling emissions. It has been estimated that by the late 18th century ambient PM levels were in excess of 300mg/m3 in London. During this period there was limited technology for pollution control and regulations (in the UK). The first regulation of emissions from industry would not be enacted until the late 1840’S.

“ENVEA have been at the forefront of environmental monitoring and process control over four decades”

Technological advancements during Industry 1.0

Whilst processes for abating emissions were not in place during the first industrial revolution, advances in science were establishing what would become the technology of the future.

Early Electrostatic Precipitator concept following Corona discharge discovery in 1824

The discovery of corona discharge as a method to remove particles from an aerosol was made in 1824 by M Hohlfeld. This lead to the invention of the Electrostatic Precipitator (ESP) by Frederick Gardner Cottrell in 1907, a method widely used today in dust and gas abatement from industrial processes.

The first electrical generator was invented in 1831 by Michael Faraday. Despite its basic design this initial invention set the foundations for the development of electrical power generation as we know it today. The discovery of electromagnetic induction has provided many innovations in Industry including wireless energy transfer which has only begun to be widely used in practical applications during the 21st century.

Particulate Emissions Control in 2019

In 2019 the methods of power generation through combustion have evolved exponentially however the methods developed during Industry 1.0 to power engines (now turbines) through combustion and the pollutants present remain broadly the same. Whilst there is now significant growth in power generation through non fossil fuels, such as EfW and Biomass, there is still estimated to be in excess of 2400 coal fired power stations (30MW and above) currently in operation globally.

Now the most tightly regulated industry for emissions, power generation through combustion employs multiple abatement methods to reduce gas and particulate emissions including flue gas desulphurisation and electrostatic precipitators. Due to the effectiveness of these abatement systems, power stations typically emit the lowest levels of particulate of any industrial process. Whilst significantly more advanced in both efficiency and scale, the basic principles of corona discharge are still central to the technology and the effectiveness of electrostatic precipitators for removing fine particles from a gas stream which is why they are still widely in use over 100 years since their inception.

Industry 4.0 in Particulate Monitoring

Due to the significantly low levels of Particulate Matter (PM) emitted from most modern power stations, continuous particulate monitors are required to measure at extremely low levels with high levels of accuracy and self diagnostic tools to verify the PM measurements.

ProScatter Particulate CEMS Installation

In the PCME ProScatterTM range, ENVEA provide a range of Light Scatter sensors (Forward Scatter and Back Scatter) used globally in power generation processes ideal for measurement after an ESP. Measuring PM emissions, often less then 1mg/m3 ProScatterTM sensors
are networked devices providing single point digital data logging from readings across multiple emission points. This data can be used to control processes ensuring any excessive emissions events are alerted to operators to avoid non-compliance and investigate any process issues.

The sensors include automated self diagnostic checks which provide early warning of both increased dust loadings and changes in particulate type as well as the ability to utilise this data to manage preventive maintenance of both abatement systems and instrumentation. PCME ProScatterTM devices are TUV and MCERTS QAL1 approved with certified measurement ranges as low as 0-7.5mg/m3 providing all the requirements for QAL2 and QAL3 processes as well as being US EPA PS-11 compliant.

With regulators globally requiring increased transparency on emissions data, PCME ProScatterTM devices can be configured to enable direct reporting of online measurement instantaneously to environmental managers and regulators.

TÜV Approved Back Scatter Particulate CEM  
ProScatter Particulate CEMS Installation
QAL1 Forward Scatter Particulate CEM

With variations of stack conditions effecting reportable PM measurements, ENVEA also provide a range of flow (velocity) sensors. The STACKFLOW range uses both Pitot and Ultrasonic technology to provide online flow or velocity readings.

These instruments can be networked alongside the PCME ProScatterTM range and readings from both devices calculated to provide normalised continuous PM measurements. Often installed with inbuilt redundancy, ENVEA systems provide a complete environmental and process control solution for measuring PM utilising the digital data analytics, automated self diagnostics and communication methods synonymous with Industry 4.0.

To learn more about the ENVEA range of instruments and further developments towards IIoT, please visit us on Stand 138 at Clean Air Technology Expo taking place on 11-12 September at the NEC, Birmingham.

In our next article we will be examining Industry 2.0, the rise of the industrial revolution, the development of early particulate measurement and how this has evolved to provide manufacturing process control capabilities in a digital age.

Part 2

Industry 2.0

Industry 2.0 (1840-1969) is marked by the evolution of the factory.
Building on the first industrial revolution, the expansion of rail and shipping alongside technological advancements in electrification and machine tools saw a large-scale transition to machine manufactured product. This paved the way for the concept of mass production, most notably within the automobile industry in the early 20th Century.
Fuelled by scientific discoveries in the world of physics and chemistry, this period also saw the introduction of many new industries.
Large scale Power Generation, Steel, Rail, Dyeing, Paper, Fertiliser, Petroleum and Automobile industries were all created during this global surge in industrialization, which would define an unprecedented period of economic growth, improved living standards and productivity.

Particulates during Industry 2.0

The rapid growth of industrial processes coincided with significant increases in airborne particulate concentrations in large cities and towns. It has been estimated that by the year 1900 ambient particulate levels had increased from 300mg/m3 during the first industrial revolution to in excess of 600mg/m3 in London. The demand for steam powered machinery in manufacturing processes led to massive increases in coal consumption reaching, at its peak, 160 million tonnes per year in the early 20th Century compared to 20 million tonnes per year in the early 1800’s.

A greater understanding of the health implications on the population (in the UK) from factory emissions developed during the second half of the 19th Century. Control of emissions from factories was included in various acts of the UK parliament between 1847–1875. This culminated in the Public Health Act (1875) which included a section on abatement and which formed the basis of current day legislation. It would be a further 80 years before specific regulation requiring the prevention of airborne particulates would be enacted within the UK. The Clean Air Act (1956) included requirements to control the emission of dark smoke from stacks specifically stating that dust emissions should be minimized. This was focused on domestic emissions introducing smokeless zones where the use of smokeless fuels was required. It would not be until the later 1968 Clean Air Act that legislative requirements for installing arrestment plant on industrial processes with defined emission limits would come into force.

Technological advancements during Industry 2.0

There were many technological advancements during the Industry 2.0 era that supported the massive expansion of manufacturing output. Many of these technologies and inventions are still in use today.
Electrification of factories grew rapidly during the early 20th Century. The invention of the electric motor enabled the concepts of mass production to be implemented with more reliable and efficient conveyer systems transporting materials through the production
process which would lay the foundations for the automated factories of the future.

The development of the modern steam turbine by Charles Parsons in 1884 coincided with the introduction of the first commercial power stations in New York and London. Parsons designs would ultimately be adapted and form the basis of large-scale power stations globally.
Steel production was revolutionised by the large-scale implementation of the Bessemer process. Patented in 1856 by Henry Bessemer, the process significantly reduced the cost and increased the speed of steel production at a time when the demand for steel in railway construction and machine tools was expanding significantly. Subsequent methods would eventually supersede this process, but this advancement is credited with supporting the rapid expansion of global trade. As the volume of industries emitting particulates through their manufacturing processes expanded and with the increased regulation on PM emissions, the need for industrial emissions abatement grew. Methods for reducing emissions from industrial stacks, including abatement methods to prevent dust emissions, emerged during the Industry 2.0 era.

In 1921, 3 filter designs were patented by Wilhelm Beth from Lübeck, Germany. Known as Dust Collectors, these designs would form the basis of the modern-day bag filter. These early designs could not be fully utilised within industry until the invention of fabrics suitable within higher temperatures in the 1970’s. The concepts would lead to filtration of particulates that both reduced emissions to air whilst effectively capturing the product integral to the manufacturing process.
The first method of monitoring particulate emissions from industrial processes was defined in 1888 by Maximilien Ringelmann. The Ringelmann Scale required the operator to view the smoke plume from the stack at distance and compare this to a chart of varying shades of grey with each shade representing the concentration of particulate matter within the plume. The method was adopted into various industries
in the early 20th Century and specified in US and UK standards for PM monitoring during the 1960’s across industry.
The Ringelmann scale was the basis for the first in-stack monitoring system using Opacity technology to provide continuous particulate monitoring.

Particulate Emissions Control in 2019

In 2019 emissions abatement is well established in all manufacturing processes producing airborne particulate. Alongside Electrostatic Precipitators (ESP), discussed in the previous article (Industry 1.0) and the modern-day baghouse, based on the initial designs of Wilhelm Beth, there are numerous other technologies now in operation globally. These include Wet Scrubbers which wash particulates and soluble pollutants from the gas stream. Dry scrubbers introduce a reagent, such as hydrated lime, to the gas stream acting as an absorbent material which neutralises acidic and often corrosive gases. These systems then require another form of filtration to remove the particulates from the process. Cyclones utilising vortex separation are also widely used as an effective method of separating solids and liquids from a gas stream.
For manufacturing processes, such as those first introduced during the second industrial revolution (Industry 2.0), baghouses
are one of the most commonly used methods of abatement.

There are many variations in design, size and operation, but all use the concept of gathering particulate on the fabric bags as the process gases are passed through the baghouse. As the bags collect particulate over time, they require cleaning to dispose of the particulate collected. In modern day bag houses, there are multiple methods of automated bag cleaning mechanisms. This includes shakers, pulse jet and reverse jet methods all of which force the PM to the base of the bag house where it is collected and often transported away via a screw feed conveyer system.

Whilst baghouses are extremely effective, they do require regular maintenance to ensure optimal performance. Bags will deteriorate over time and a gross bag filter failure can led to excessively high emissions and loss of valuable product. As well as monitoring and maintaining the filter media, ensuring the operation of automated mechanisms for bag cleaning and transportation from the collector is essential. The costs associated with plant shutdown, replacement bags, lost product and high emission events have led to the development of technologies to manage the performance of bag houses. This includes managing preventative maintenance scheduling, reducing the time required to identify and replace failed filter media and providing early warning of potentially high emission events.

Industry 4.0 in Particulate Monitoring

With its ElectroDynamic technology, ENVEA provide a wide range of particulate monitors providing both real time continuous dust concentration measurement and indicative monitoring to identify PM levels both within and immediately after bag filters.

Instruments from the PCME LEAK LOCATE and LEAK ALERT range

ElectroDynamic® Filter Dust/Leak Monitor
ElectroDynamic® Broken Bag Detector

The PCME LEAK LOCATE and LEAK ALERT range enables operators to monitor directly on the outlets from each compartment of bags giving real-time trends of particulate levels within specific sections of the baghouse.

For baghouses with online cleaning cycles the dust levels exiting each outlet will increase with each cleaning pulse. These emission peaks are logged by the sensor. As the condition and performance of bags within each compartment deteriorate the resulting dust levels will increase. By utilising ENVEA software tools, operators can therefore identify compartments that are starting to deteriorate and manage the maintenance of their baghouse accordingly.

FlowJam and ProGap ensure continuous material flow
FlowJam and ProGap ensure continuous material flow

Gross filter failures can be identified as soon as they occurs enabling the operator to bypass the compartment and investigate and resolve the issue before it leads to a high emissions event. This data, when viewed over time, can provide trends which can be used to measure the rate of deterioration and assist in the assessment of expected mean time to failure.

The effective management of baghouse performance utilising the LEAK LOCATE system can therefore reduce costs and inefficiencies associated with filter failure whilst providing valuable process data to further improve the efficiency of the manufacturing process.

Point level monitoring

In addition to particulate monitoring, ENVEA now offer a range of bulk powder flow measurement instruments. By installing the SOLIDFLOW 2.0 system on the screw feed conveyer at the base of the bag filter, operators can monitor the mass flow of material collected as it is transported away from the bag house. Additional sensors such as the Flow-Jam (flow/no flow) sensor and ProGap level detection instrument can also be installed within the ducting and hoppers to ensure material flow is continuous and no blockages or overflow occurs all of which can affect ongoing operation.

By combining the data and trends provided through the ENVEA range of process instruments, operators can manage their processes at each stage of filtration providing the interconnected factory concept synonymous with Industry 4.0.

Part 3

Industry 3.0

Industry 3.0 (1969–2012), often referred to as the digital revolution, was centred around the emergence of computing in manufacturing process.

Following the transition to mass production methods during Industry 2.0 the automation of manufacturing lines through the digital revolution was a significant leap forward in Industry. As with the development of mass production methods in the early 20th century, this era of automation was pioneered within the automobile industry but would ultimately be adopted across manufacturing sectors.

The introduction of Programmable Logic Controllers (PLCs) allowed manufacturing industries to develop repeatable, consistent and controlled manufacturing processes that did not rely solely on human interaction and which allowed manufacturing capacity to expand beyond previous limitations of the workforce. The development of robotics supporting these manufacturing processes allowed wide scale adoption of PLCs and automated processes across industry. With advancements in computing power and the evolution of microprocessors, the benefits associated with automated process control were realised in most industrial sectors.

Supervisory Control and Data Acquisition (SCADA) systems allowed industries to combine the control and precision of automated processes with data monitoring and analytics to better inform and manage processes with developments in networked systems allowing visibility across plant. Whilst there were many significant technological advancements during this period it is the emergence of large-scale computing in a digital age that underpinned the third industrial revolution.

Particulates during Industry 3.0

The development of particulate abatement from industrial process throughout the 20th century coupled with early particulate monitoring techniques and regulation had dramatically reduced particulate emissions from the early days of the first and second industrial revolution.

The Industry 3.0 era would see the birth of environmental monitoring as an industry in its own right with technological advancements in instrumentation coupled with increased regulation in western industrialised nations.

The development of a range of effective particulate matter abatement methods (discussed in the previous article) driven by the demand for ever decreasing emissions and awareness of the health risks associated with ultra-fine particles drove the demand for more sophisticated technologies in measuring particulate matter emissions.

ElectroDynamic® particulate emission measurement technology principle

Alongside the development of isokinetic sampling techniques, the process of extracting, drying and weighing particulate samples from industrial emissions, a range of new technologies emerged enabling continuous particulate monitoring.

In 1990 PCME Ltd. was formed. Utilising its patented ElectroDynamic® technology, it provided a range of continuous monitoring systems that could provide accurate representations of dust concentrations within stacks and outlets from abatement processes.

The correlation between AC electrical charge characteristics of particles and dust concentrations, calibrated to isokinetic samples, enabled validated and certified measurements both supporting compliance to regulation and process control.

Technological advancements during Industry 3.0

Further measurement technologies, such as forward scatter, backscatter and dynamic opacity, would emerge during the early part of the 21st century and as the understanding of the response of varying dust signals in relation to operational performance evolved, tools to analyse the particulate emissions data emerged to support both environmental and process monitoring.

Communication methods, such as 4-20 mA outputs and Modbus protocols, for data transfer across wider network systems evolved and the data from particulate sensors became integrated into the PLC and SCADA systems synonymous with Industry 3.0. As well as providing the capability to monitor and report emission limits in line with operating permits, data taken from these sensors, fed through control systems enabled process operators to find cost and efficiency savings through particulate matter readings supporting preventative and scheduled maintenance of abatement systems such as baghouses.

Data Viewer provides graphical analysis of emission trends and events

This led to the development of software packages, such as PC-ME DUST TOOLS, providing even greater analytical capabilities to process operators collecting and storing data from large networked system of sensors across site giving even greater control and visibility from the control room.

As with most industries, the methods and principles of automated factories, the use of PLCs and data capture and storage are integral to current continuous particulate monitoring. The techniques and systems used to drive the modern factory work in harmony with the instruments and data used to monitor their particulate emissions.

In 2019 particulate emissions are monitored in multiple locations across industrial sites. The most heavily regulated industries are required to continuously monitor any particulate emissions to air. The benefits achieved through monitoring at various locations throughout the process, including through various stages of abatement, requires multiple sensors positioned at various locations across site.

Particulate Emissions Control in 2019

ENVEA provide the capability for these sensors to be networked through a single multi-channel control system.

With the ProController Multi-Channel system, up to 32 channels can be connected to a single device utilising a variety of network devices to extend both power and communication transfer across many hundreds of metres whilst maintaining constant reporting and logging of the critical data.

The ProController system can control sensor types across the range of technologies allowing sites to establish a network of ENVEA particulate and flow instruments regardless of the differing technologies required at each measurement point.

The system enables the data to be captured with a variety of logging options, averaging results to meet permit and process control requirements.

The control functions within the ProController enable a level of programmable logic control, pioneered during Industry 3.0, with control of automated self checks, calculations of results to manage process normalisation for environmental reporting and the ability to take in digital signals from plant control systems, such as the plant stop function, which tags data recorded during process downtime.

A range of alarm functions are available to the operator via the ProController system. These alarms alert the operator to increases in readings, providing early warning to deteriorating abatement processes, reducing downtime and avoiding breach events. They also alert the operator to power or communication interruptions across the network as well as providing status alarms for instrument self-check results.

Isokinetic sampling train used to extract particulate samples in order to calibrate particulate monitoring systems

In addition to the local control, a full range of communication methods are available for output of the data and alarms. Signals can be taken in real time over 4-20 mA or RS485 directly back to plant-wide PLCs, allowing constant monitoring of sensor readings and alarm status.

The development of Ethernet networking capabilities has expanded the reach of networked devices. With Ethernet connectivity as standard, the ProController can be added to a sites network allowing secure communication both to and from the controller across site.

For sites without existing data capture and control systems, or those requiring a more advanced analytical tool, ENVEA provide the PC-ME DUST TOOLS software. As well as providing continuous communication to the controller with real time measurement and reporting tools, commands and sensor configurations can be backed up and generated within the software. Automatic download of data is available with analytical tools, such as PREDICT (discussed in the previous article) which enables sites to better manage baghouse performance.

The ProController provides flexibility for sensor configuration, networking, data output and control functions. It enables sites to integrate the range of ENVEA Particulate and flow systems into sophisticated PLC systems and via PC-ME DUST TOOLS software enabling the level of automation and control developed throughout Industry 3.0 in the world of particulate and flow monitoring.

Industry 4.0 in Particulate Monitoring

Now, as we enter the fourth industrial revolution (Industry 4.0 – Industrial Internet of Things) ENVEA is well placed to provide the tools required to enable the transition from local area network control to CLOUD-based computing and data storage with interconnected factories and automated process.

As discussed in our first article, the technology and functionality within the ENVEA range of sensors provides the capability to effectively manage compliance to operating permits for Particulate emissions with combined particulate and flow measurements.

This includes the automated self-checks with active logging to validate the readings meeting the requirement under EN 14181 and PS-11. The networking, logging and reporting capabilities of the ENVEA multi-channel control system and PC-ME DUST TOOLS software coupled with this sensor technology ensure this data is available to operators and can be submitted to regulators in the required format.

Centralised particulate emission and flow data logging for regulatory and process data analysis

The benefits of the LEAK LOCATE range of sensors, discussed in our second article, demonstrates how the concept of preventative maintenance through data analysis can be achieved utilising PC-ME DUST TOOLS software and interconnected signals from plant operations to more effectively manage baghouse performance.

The network capabilities of these sensors ensure centralised data logging with the capability to store and output this data to PC-ME DUST TOOLS and site-wide PLCs.