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.

At Clean Air Technology Expo taking place on 11-12 September at the NEC, Birmingham, ENVEA will be demonstrating its range of Particulate Emissions Instruments alongside its advancements in data capture, storage and analytics that will combine the world of industrial particulate and flow monitoring with the latest in smart technology.

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.

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  QAL1 Forward Scatter Particulate CEM
  ProScatterTMand Backscatter Particulate CEMS

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.

ElectroDynamic® Filter Dust/Leak MonitorInstruments from the PCME LEAK LOCATE and LEAK ALERT range

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.

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.

FlowJam and ProGap ensure continuous material flow

FlowJam and ProGap ensure continuous material flow

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.