Industry Overview: Food and Beverage 

The food and beverage (F&B) industry includes all companies involved in processing raw food materials, as well as those packaging and distributing them. This includes fresh, prepared foods as well as packaged foods, and both alcoholic and non-alcoholic beverages. 

The food and beverage industry is divided into two major segments, which are the production and the distribution of edible goods. The first group, production, includes the processing of meats and cheeses and the creation of soft drinks, alcoholic beverages, packaged foods, and other modified foods. Any product meant for human consumption, aside from pharmaceuticals, passes through this sector. Production also covers the processing of meats, cheeses and packaged foods, dairy and alcoholic beverages. The production sector excludes foods and fresh produce that are directly produced via farming, as these fall under agriculture. 

The manufacture and processing of food and beverages create substantial risks of fire and toxic gas exposure. Many gases are used for baking, processing and refrigerating foods. These gases can be highly hazardous – either toxic, flammable, or both. 

Gas Hazards 

Food Processing

Secondary food processing methods includes fermentation, heating, chilling, dehydration or cooking of some kind. Many types of commercial food processing consist of cooking, especially industrial steam boilers. Steam boilers are usually gas-fired (natural gas or LPG) or use a combination of gas and fuel oil. For gas-fired steam boilers, natural gas consists mainly of methane (CH4), a highly combustible gas, lighter than air, which is piped directly into boilers. In contrast, LPG consists mainly of propane (C3H8), and usually requires an on-site fuel storage tank. Whenever flammable gases are used on site, forced mechanical ventilation must be included in storage areas, in case of leakage. Such ventilation is usually triggered by gas detectors that are installed near boilers and in storage rooms. 

Chemical Disinfection 

The F&B industry takes hygiene very seriously, as the slightest contamination of surfaces and equipment can provide an ideal breeding ground for all kinds of germs. The F&B sector therefore demands rigorous cleaning and disinfection, which must meet industry standards. 

There are three methods of disinfection commonly used in F&B: thermal, radiation and chemical. Chemical disinfection with chlorine-based compounds is by far the most common and effective way to disinfect equipment or other surfaces. This is because chlorine-based compounds are inexpensive, fast acting and effective against a variety of microorganisms. Several different chlorine compounds are commonly used, of which include hypochlorite, organic and inorganic chloramines, and chlorine dioxide. Sodium hypochlorite solution (NaOCl) is stored in tanks while chlorine dioxide (ClO2) gas is usually generated on site.  

In any combination, chlorine compounds are hazardous and exposure to high concentrations of chlorine can cause severe health issues. Chlorine gases are usually stored on site and a gas detection system should be installed, with a relay output to trigger ventilation fans once a high level of chlorine is detected. 

Food Packaging 

Food packaging serves many purposes; it allows food to be transported and stored safely, protects food, indicates portion sizes and provides information about the product. To keep food items safe for a long time, it is necessary to remove oxygen from the container because otherwise, oxidation will occur when the food comes into contact with oxygen. The presence of oxygen also promotes bacterial growth, which is harmful when consumed. However, if the package is flushed with nitrogen, the shelf life of packaged food can be extended. 

Packagers often use nitrogen (N2) flushing methods for preserving and storing their products. Nitrogen is a non-reactive gas, non-odorous and non-toxic. It prevents oxidation of fresh food with sugars or fats, stops the growth of dangerous bacteria and inhibits spoilage. Lastly, it prevents packages from collapsing by creating a pressurized atmosphere. Nitrogen can be generated on site using generators or delivered in cylinders. Gas generators are cost effective and provide an uninterrupted supply of gas. Nitrogen is an asphyxiant, capable of displacing oxygen in air. Because it has no smell and is non-toxic, workers may not become aware of low oxygen conditions before it is too late.  

Oxygen levels below 19% will cause dizziness and loss of consciousness. To prevent this, oxygen content should be monitored with an electrochemical sensor. Installing oxygen detectors in packaging areas ensures the safety of workers and early detection of leaks. 

Refrigeration Facilities 

Refrigeration facilities in the F&B industry are used to keep food cool for long periods of time. Large-scale food storage facilities often use cooling systems based on ammonia (> 50% NH3), as it is efficient and economical. However, ammonia is both toxic and flammable; it is also lighter than air and fills up enclosed spaces rapidly. Ammonia can become flammable if released in an enclosed space where a source of ignition is present, or if a vessel of anhydrous ammonia is exposed to fire.   

Ammonia is detected with electro-chemical (toxic) and catalytic (flammable) sensor technology. Portable detection, including single- or multi-gas detectors, can monitor instantaneous and TWA exposure to toxic levels of NH3. Multi-gas personal monitors have been shown to improve workers’ safety where a low-range ppm for routine system surveys and flammable range is used during system maintenance. Fixed detection systems include a combination of toxic- and flammable-level detectors connected to local control panels – these are usually supplied as part of a cooling system. Fixed systems can also be used for process over-rides and ventilation control. 

Brewing and Drinks Industry 

The risk involved in the manufacture of alcohol involves sizable manufacturing equipment which can be potentially harmful, both to operate and because of the fumes and vapours that can be emitted into the atmosphere and subsequently impact the environment. Ethanol is the main combustible hazard found within distilleries and breweries is the fumes and vapours produced by ethanol. With the capacity to be emitted from leaks in tanks, casks, transfer pumps, pipes and flexible hoses, ethanol vapour is a very real fire and explosion hazard faced by those in the distillery industry. Once the gas and vapour is released into the atmosphere, it can quickly build and pose a danger to the health of workers. It is worth noting here however, that the concentration required to cause harm to workers’ health has to be very high. With this in mind, the more significant risk from ethanol in the air is that of explosion. This fact reinforces the importance of gas detection equipment to recognise and remedy any leaks straight away, so as to avoid disastrous consequences. 

Packaging, Transport and Dispensing 

Once wine is bottled and beer is packaged, they must be delivered to the relevant outlets. This commonly includes distribution companies, warehousing and in the case of breweries, draymen. Beer and soft drinks use carbon dioxide or a mix of carbon dioxide and nitrogen as a way of delivering a beverage to the ‘tap’. These gases also give beer a longer-lasting head and improve the quality and taste. 

Even when the beverage is ready to deliver, gas-related hazards remain. Those arise in any activity at premises that contain compressed gas cylinders, due to the risk of increased carbon dioxide levels or depleted oxygen levels (due to high levels of nitrogen). Carbon dioxide (CO2) occurs naturally in the atmosphere (0.04%). CO2  is colourless and odourless, heavier than air and if it escapes, will tend to sink to the floor. CO2 collects in cellars and at the bottom of containers and confined spaces such as tanks and silos. CO2  is generated in large amounts during fermentation. It is also injected into beverages during carbonation. 

To find out more on the gas hazards in food and beverage production visit our industry page for more information. 

The importance of Gas Detection in the Water and Wastewater Industry 

Water is vital to our daily lives, both for personal and domestic use and industrial/commercial applications. Whether a facility focuses on the production of clean, potable water or treating effluent, Crowcon is proud to serve a wide variety of water industry clients, providing gas detection equipment that keeps workers safe around the world. 

Gas Hazards 

Apart from common gas hazards known in the industry; methane, hydrogen sulphide, and oxygen, there are bi-product gas hazards and cleaning material gas hazards that occur from purifying chemicals such as ammonia, chlorine, chlorine dioxide or ozone that are used in the decontamination of the waste and effluent water, or to remove microbes from clean water. There is great potential for many toxic or explosive gases to exist as a result of the chemicals used in the water industry. And added to these are chemicals that may be spilled or dumped into the waste system from industry, farming or building work. 

Safety Considerations  

Confined Space Entry 

The pipelines used to transport water require regular cleaning and safety checks; during these operations, portable multi-gas monitors are used to protect the workforce. Pre-entry checks must be completed prior to entering any confined space and commonly O2, CO, H2S and CH4 are monitored. Confined spaces are small, so portable monitors must be compact and unobtrusive for the user, yet able to withstand the wet and dirty environments in which they must perform. Clear and prompt indication of any increase in gas monitored (or any decrease for oxygen) is of paramount importance – loud and bright alarms are effective in raising the alarm to the user. 

Risk assessment 

Risk assessment is critical, as you need to be aware of the environment that you are entering and thus working in. Therefore, understanding the applications and identifying the risks regarding all safety aspects. Focusing on gas monitoring, as part of the risk assessment, you need to be clear on what gases may be present.  

Fit for purpose 

There is a variety of applications within the water treatment process, giving the need to monitor multiple gases, including carbon dioxide, hydrogen sulphide, chlorine, methane, oxygen, ozone and chlorine dioxide. Gas detectors are available for single or multiple gas monitoring, making them practical for different applications as well as making sure that, if conditions change (such as sludge is stirred up, causing a sudden increase in hydrogen sulphide and flammable gas levels), the worker is still protected.  

Legislation   

European Commission Directive 2017/164 issued in January 2017, established a new list of indicative occupational exposure limit values (IOELVs). IOELV are health-based, non-binding values, derived from the most recent scientific data available and considering the availability of reliable measurement techniques. The list includes carbon monoxide, nitrogen monoxide, nitrogen dioxide, sulphur dioxide, hydrogen cyanide, manganese, diacetyl and many other chemicals. The list is based on Council Directive 98/24/EC that considers the protection of the health and safety of workers from the risks related to chemical agents in the workplace. For any chemical agent for which an IOELV has been set at Union level, Member States are required to establish a national occupational exposure limit value. They also are required to take into account the Union limit value, determining the nature of the national limit value in accordance with national legislation and practice. Member States will be able to benefit from a transitional period ending at the latest on 21 August 2023.  

The Health and Safety Executive (HSE) state that each year several workers will suffer from at least one episode of work-related illness. Although, most illnesses are relatively mild cases of gastroenteritis, there is also a risk for potentially fatal diseases, such as leptospirosis (Weil’s disease) and hepatitis. Even though these are reported to the HSE, there could be significant under-reporting as there is often failure to recognise the link between illness and work.  

Under domestic law of the Health and Safety at Work etc Act 1974, employers are responsible for ensuring the safety of their employees and others. This responsibility is reinforced by regulations. 

The Confined Spaces Regulations 1997 applies where the assessment identifies risks of serious injury from work in confined spaces. These regulations contain the following key duties: 

  • Avoid entry to confined spaces, e.g., by doing the work from the outside. 
  • If entry to a confined space is unavoidable, follow a safe system of work.
  • Put in place adequate emergency arrangements before the work start. 

The Management of Health and Safety at Work Regulations 1999 requires employers and self-employed people to carry out a suitable and sufficient assessment of the risks for all work activities for the purpose of deciding what measures are necessary for safety. For work in confined spaces this means identifying the hazards present, assessing the risks and determining what precautions to take. 

Our solutions

Elimination of these gas hazards is virtually impossible, so permanent workers and contractors must depend on reliable gas detection equipment to protect them. Gas detection can be provided in both fixed and portable forms. Our portable gas detectors protect against a wide range of gas hazards, these include T4x, Clip SGD, Gasman, Tetra 3,Gas-Pro, T4 and Detective+. Our fixed gas detectors are used in many applications where reliability, dependability and lack of false alarms are instrumental to efficient and effective gas detection, these include Xgard, Xgard Bright and IRmax. Combined with a variety of our fixed detectors, our gas detection control panels offer a flexible range of solutions that measure flammable, toxic and oxygen gases, report their presence and activate alarms or associated equipment, for the wastewater industry our panels include Gasmaster.    

To find out more on the gas hazards in wastewater and water treatment visit our industry page for more information.  

Construction and Key Gas Challenges

Workers in the construction industry are at risk from a wide variety of hazardous gases including Carbon Monoxide (CO), Chlorine Dioxide (CLO2), Methane (CH4), Oxygen (O2), Hydrogen Sulphide (H2S) and Volatile Organic Compounds (VOC’s). 

Through the use of specific equipment, transport and the undertaking of sector specific activities, construction is a main contributor to the emission of toxic gases into the atmosphere, which also means construction personnel are more at risk of ingestion of these toxic contaminants. 

Gas challenges can be found in a variety of applications including building material storage, confined spaces, welding, trenching, land clearing and demolition. Ensuring the protection of workers within the construction industry from the multitude of hazards they may encounter is very important. With a specific focus on safeguarding teams from harm by, or the consumption of, toxic, flammable and poisonous gases. 

Gas Challenges 

Confined Space Entry 

Workers are more at risk from hazardous gases and fumes when they are operating within confined spaces.  Those entering these spaces need to be protected from the presence of flammable or/and toxic gases such as Volatile Organic Compounds (ppm VOC), Carbon Monoxide (ppm CO) and Nitrogen Dioxide (ppm NO2). Undertaking clearance measurements and pre-entry safety checks are paramount to ensure safety before a worker enters the space. Whilst in confined spaces gas detection equipment must be worn ongoingly in case of environmental shifts which make the space no longer safe to work in, due to a leak for example, and evacuation is needed. 

Trenching and Shoring 

During excavation works, such as trenching and shoring, construction workers are at risk of inhaling harmful gases generated by degradable materials present in certain ground types. If undetected, as well as posing risks to the construction workforce, they can also migrate through subsoil and cracks into the completed building and harm housing residents. Trenched areas can also have reduced oxygen levels, as well as contain toxic gases and chemicals. In these cases atmospheric testing should be performed in excavations that exceed four feet. There is also the risk of hitting utility lines when digging which can cause natural gas leaks and lead to worker fatalities. 

Building Material Storage  

Many of the materials used within construction can release toxic compounds (VOC’s). These can form in a variety of states (solid or liquid) and come from materials such as adhesives, natural and plywood’s, paint, and building partitions. Pollutants include phenol, acetaldehyde and formaldehyde. When ingested, workers can suffer from nausea, headaches, asthma, cancer and even death. VOCs are specifically dangerous when consumed within confined spaces, due to the risk of asphyxiation or explosion. 

Welding and Cutting 

Gases are produced during the welding and cutting process, including carbon dioxide from the decomposition of fluxes, carbon monoxide from the breakdown of carbon dioxide shielding gas in arc welding, as well as ozone, nitrogen oxides, hydrogen chloride and phosgene from other processes. Fumes are created when a metal is heated above its boiling point and then its vapours condense into fine particles, known as solid particulates. These fumes are obviously a hazard for those working in the sector and  illustrate the importance of reliable gas detection equipment to reduce exposure. 

Health and Safety Standards 

Organisations working in the construction sector can prove their credibility and safety operationally by gaining ISO certification. ISO (International Organisation for Standardisation) certification is split across multiple different certificates, all of which recognise varying elements of safety, efficiency and quality within an organisation. Standards cover best practice across safety, healthcare, transportation, environmental management and family. 

Although not a legal requirement, ISO standards are widely recognised as making the construction industry a safer sector by establishing global design and manufacturing definitions for almost all processes. They outline specifications for best practice and safety requirements within the construction industry from the ground up. 

In the UK, other recognised safety certifications include the NEBOSH, IOSH and CIOB courses which all offer varied health and safety training for those in the sector to further their understanding of working safely in their given field.  

To find out more on the gas challenges in construction visit our industry page for more information. 

The Dangers of Gas in Farming and Agriculture 

Farming and agriculture is a colossal industry the world over, providing more than 44 million jobs in the EU and making up over 10% of total US employment. 

With a wide range of processes involved in this sector, there are bound to be hazards that must be considered. These include gas hazards from the likes of methane, hydrogen sulphide, ammonia, carbon dioxide and nitrous oxide. 

Methane is a colourless, odourless gas which can have harmful effects on humans resulting in slurred speech, vision problems, memory loss, nausea and in extreme cases can impact breathing and heartrate, potentially leading to unconsciousness and even death. In agricultural environments, it is created through anaerobic digestion of organic material, such as manure. The amount of methane generated is exacerbated in areas which are poorly ventilated or high in temperature, and in areas with particular lack of airflow, the gas can build up, become trapped and cause explosions. 

Carbon dioxide (CO2) is a gas which is naturally produced in the atmosphere, levels of which can be heightened by agricultural processes. CO2 can be emitted by a range of farming process including crop and livestock production and is also emitted by some equipment which is used in agricultural applications. Storage spaces used for waste and grain and sealed silos are of particular concern due to the capacity for CO2 to build up and displace oxygen, increasing suffocation risk for both animals and humans alike. 

Similarly, to methane, hydrogen sulphide comes from the anaerobic decomposition of organic material and can also be found in a range of agricultural processes relating to the production and consumption of biogas. H2S prevents oxygen from being carried to our vital organs and areas where it builds up often have reduced oxygen concentrations, furthering the risk of asphyxiation where H2S levels are high. Whilst it could be considered easier to detect due its distinct ‘rotten egg’ smell, the intensity of the smell actually decreases at higher concentrations and prolonged exposure. At high levels, H2S can cause severe irritation of, and fluid build-up in the lungs and impact the nervous system. 

Ammonia (NH3) is a gas found in animal waste which is often then spread and emitted further through slurry spreading on agricultural land. As with many of the gases covered, the impact of ammonia is heightened when there is a lack of ventilation. It is harmful to the wellbeing of both livestock and humans, causing respiratory diseases in animals whilst high levels can lead to burns and swelling of the airways and lung damage in humans and can be fatal. 

Nitrogen oxide (NO2) is another gas to be aware of in the agriculture and farming industry. It is present in synthetic fertilisers which are often used in more intensive farming practices to ensure greater crop yields. The potential negative health impacts of NO2 in humans include reduced lung function, internal bleeding, and ongoing respiratory problems.  

Workers in this industry are frequently on the move, and for this specific purpose Crowcon offers a wide range of fixed and portable gas detectors to keep workers safe. Crowcon’s portable range comprises T4, Gas-Pro, Clip SGD and Gasman all of which offer reliable, transportable detection capacities for a variety of gases. Our fixed gas detectors are used where reliability, dependability and lack of false alarms are instrumental to efficient and effective protection of assets and areas, and include the Xgard and Xgard Bright. Combined with a variety of our fixed detectors, our gas detection control panels offer a flexible range of solutions that measure flammable, toxic and oxygen gases, report their presence and activate alarms or associated equipment, for the farming and agriculture industry we often recommend our Gasmaster, Vortex and Addressable Controllers panels.

To find out more on the gas hazards in farming and agriculture visit our industry page for more information.

Gold Mining: What gas detection do I need? 

How is gold mined?

Gold is a rare substance equating to 3 parts per billion of the earth’s outer layer, with most of the world’s available gold coming from Australia. Gold, like iron, copper and lead, is a metal. There are two primary forms of gold mining, including open-cut and underground mining. Open mining involves earth-moving equipment to remove waste rock from the ore body above, and then mining is conducted from the remaining substance. This process requires waste and ore to be struck at high volumes to break the waste and ore into sizes suitable for handling and transportation to both waste dumps and ore crushers. The other form of gold mining is the more traditional underground mining method. This is where vertical shafts and spiral tunnels transport workers and equipment into and out of the mine, providing ventilation and hauling the waste rock and ore to the surface.

Gas detection in mining

When relating to gas detection, the process of health and safety within mines has developed considerably over the past century, from morphing from the crude usage of methane wick wall testing, singing canaries and flame safety to modern-day gas detection technologies and processes as we know them. Ensuring the correct type of detection equipment is utilised, whether fixed or portable, before entering these spaces. Proper equipment utilisation will ensure gas levels are accurately monitored, and workers are alerted to dangerous concentrations within the atmosphere at the earliest opportunity.

What are the gas hazards and what are the dangers?

The dangers those working within the mining industry face several potential occupational hazards and diseases, and the possibility of fatal injury. Therefore, understanding the environments and hazards, they may be exposed to is important.

Oxygen (O2)

Oxygen (O2), usually present in the air at 20.9%, is essential to human life. There are three main reasons why oxygen poses a threat to workers within the mining industry. These include oxygen deficiencies or enrichment, as too little oxygen can prevent the human body from functioning leading to the worker losing consciousness. Unless the oxygen level can be restored to an average level, the worker is at risk of potential death. An atmosphere is deficient when the concentration of O2 is less than 19.5%. Consequently, an environment with too much oxygen is equally dangerous as this constitutes a greatly increased risk of fire and explosion. This is considered when the concentration level of O2 is over 23.5%

Carbon Monoxide (CO)

In some cases, high concentrations of Carbon Monoxide (CO) may be present. Environments that this may occur include a house fire, therefore the fire service are at risk of CO poisoning. In this environment there can be as much as 12.5% CO in the air which when the carbon monoxide rises to the ceiling with other combustion products and when the concentration hits 12.5% by volume this will only lead to one thing, called a flashover. This is when the whole lot ignites as a fuel. Apart from items falling on the fire service, this is one of the most extreme dangers they face when working inside a burning building. Due to the characteristics of CO being so hard to identify, I.e., colourless, odourless, tasteless, poisonous gas, it may take time for you to realise that you have CO poisoning. The effects of CO can be dangerous, this is because CO prevents the blood system from effectively carrying oxygen around the body, specifically to vital organs such as the heart and brain. High doses of CO, therefore, can cause death from asphyxiation or lack of oxygen to the brain. According to statistics from the Department of Health, the most common indication of CO poisoning is that of a headache with 90% of patients reporting this as a symptom, with 50% reporting nausea and vomiting, as well as vertigo. With confusion/changes in consciousness, and weakness accounting for 30% and 20% of reports.

Hydrogen sulphide (H2S)

Hydrogen sulphide (H2S) is a colourless, flammable gas with a characteristic odour of rotten eggs. Skin and eye contact may occur. However, the nervous system and cardiovascular system are most affected by hydrogen sulphide, which can lead to a range of symptoms. Single exposures to high concentrations may rapidly cause breathing difficulties and death.

Sulphur dioxide (SO2)

Sulphur dioxide (SO2) can cause several harmful effects on the respiratory systems, in particular the lung. It can also cause skin irritation. Skin contact with (SO2) causes stinging pain, redness of the skin and blisters. Skin contact with compressed gas or liquid can cause frostbite. Eye contact causes watering eyes and, in severe cases, blindness can occur.

Methane (CH4)

Methane (CH4) is a colourless, highly flammable gas with a primary component being that of natural gas. High levels of (CH4) can reduce the amount of oxygen breathed from the air, which can result in mood changes, slurred speech, vision problems, memory loss, nausea, vomiting, facial flushing and headache. In severe cases, there may be changes in breathing and heart rate, balance problems, numbness, and unconsciousness. Although, if exposure is for a longer period, it can result in fatality.

Hydrogen (H2)

Hydrogen Gas is a colourless, odourless, and tasteless gas which is lighter than air. As it is lighter than air this means it float higher than our atmosphere, meaning it is not naturally found, but instead must be created. Hydrogen poses a fire or explosion risk as well as an inhalation risk. High concentrations of this gas can cause an oxygen-deficient environment. Individuals breathing such an atmosphere may experience symptoms which include headaches, ringing in ears, dizziness, drowsiness, unconsciousness, nausea, vomiting and depression of all the senses

Ammonia (NH3)

Ammonia (NH3) is one of the most widely used chemicals globally that is produced both in the human body and in nature. Although it is naturally created (NH3) is corrosive which poses a serve concern for health. High exposure within the air can result in immediate burning to the eyes, nose, throat and respiratory tract. Serve cases can result in blindness.

Other gas risks

Whilst Hydrogen Cyanide (HCN) doesn’t persist within the environment, improper storage, handling and waste management can pose severe risk to human health as well as effects on the environment. Cyanide interferes with human respiration at cellular levels that can cause serve and acute effects, including rapid breathing, tremors, asphyxiation.

Diesel particulate exposure can occur in underground mines as a result of diesel-powered mobile equipment used for drilling and haulage. Although control measures include the use of low sulphur diesel fuel, engine maintenance and ventilation, health implication includes excess risk of lung cancer.

Products that can help to protect yourself

Crowcon provide a range of gas detection including both portable and fixed products all of which are suitable for gas detection within the mining industry.

To find out more visit our industry page here.

What is Biogas?

Biogas most commonly known as biomethane is a renewable fuel constructed through the breakdown of organic matter (such as animal manure, municipal rubbish/ waste, plant material, food waste or sewage) by bacteria in an oxygen-free environment through a process called anaerobic digestion. Biogas systems use anaerobic digestion to repurpose these organic materials, converting them into biogas, of which consists of both energy (gas), and valuable soil products (liquids and solids). It can be used for many different functions; these include vehicle fuel and for heating and electricity generation.  

What industries is Biogas used in?

Biogas can be produced through the combustion process to produce heat only. When burned, one cubic metre of biogas produces around 2.0/2.5 kWh of thermal energy, providing the nearby buildings with the heat generated. The unused heat is dismissed, and unless it is heated and converted into hot water through a local pipe network into local houses, it is wasted. This concept of heating water and transferring to homes as part of central heating is popular in some Scandinavian countries. 

Biogas is eligible for support under the Renewable Transport Fuel Obligation due to the combustion of biomethane from vehicles being more environmentally friendly than those who use transport fuels such as modern petrol and diesel, thereby helping reduce greenhouse emissions. Examples of renewable transport fuels in vehicles that are formed out of biogas are compressed natural gas (CNG) or liquefied natural gas (LNG).  

Electricity can be generated from the combustion of biogas. Electricity is easier to transport and measure than heat and gas supply, however, requires the right infrastructure in order for it to feed into the grid, that is expensive and complex. Although, generating green electricity can benefit the generators (households and communities) by using the Feed-in Tariffs (FiTs) or for bigger players can maximise the Renewable Obligation Certificates (ROCs) for industrial scale production, thereby leading to a reduction in cost as well as being better for the environment. 

Other industries include hospitality, manufacturing, retail and wholesale. 

Which gases does Biogas contain? 

Biogas consists mainly of methane and carbon dioxide. The most common ratio is 60% CH4 (methane) and 40% CO2 (carbon dioxide), However, the respective quantities of these will vary depending on the type of waste involved in the production of the resulting biogas, therefore the most common ratio will be 45 to 75% methane and carbon dioxide from 55 to 25%. Biogas also contains small amounts of hydrogen sulphide, siloxanes and some moisture.  

What are the key benefits?

There are several reasons why biogas technology is useful as an alternate form of technology: Primarily, the raw material used is very cheap, and to farmers it is practically free with the biogas having the ability to be used for a range of household and farming applications. The burning of biogas does not produce harmful gases; therefore, it is environmentally clean. One of the most convenient benefits of biogas is that the technology required for its production is relatively simple and can be reproduced in large or small scale without the need for a large initial capital investment. As this type of energy is a renewable, clean source of energy that relies on a carbon-neutral process, therefore no new amounts of carbon are released into the atmosphere when using biogas. As well as it helping to divert food waste from landfills, positively impacting the environment and economics. Biogas also helps to reduce soil and water contamination from animal and human waste, allowing for the maintenance of a healthy and safe environment for many communities worldwide. With methane being a contributor to climate change, biogas contributes to its reduction that is emitted into the atmosphere, helping to counteract its impact on climate change, thereby helping to possibly help with its immediate impact on the environment.  

However, biogas as a source of energy does have its disadvantages, one is that Biogas production is dependent on a biological process that doesn’t have the ability to be controlled fully. Additionally, biogas works better in warmer climates, this consequently means biogas doesn’t have the capacity to be accessible equally worldwide. 

Is Biogas Good or Bad?

Biogas is an outstanding source of clean energy, due to it possessing a lower impact on the environment than fossil fuels. Although biogas doesn’t have a zero impact on the ecosystems, it is carbon neutral. This is because biogas is produced from plant matter, of which has previously fixed carbon from carbon dioxide in the atmosphere. A balance between the carbon being let out as a result of producing biogas and the amount absorbed from the atmosphere is maintained. 

Identifying Leaks from Natural Gas pipelines at a Safe Distance

The use of natural gas, of which methane is the principle component, is increasing worldwide. It also has many industrial uses, such as the manufacture of chemicals like ammonia, methanol, butane, ethane, propane and acetic acid; it is also an ingredient in products as diverse as fertilizer, antifreeze, plastics, pharmaceuticals and fabrics.

Natural gas is transported in several ways: through pipelines in gaseous form; as liquefied natural gas (LNG) or compressed natural gas (CNG). LNG is the normal method for transporting the gas over very long distances, such as across oceans, while CNG is usually carried by tanker trucks over short distances. Pipelines are the preferred transport choice for long distances over land (and sometimes offshore), such as between Russia and central Europe. Local distribution companies also deliver natural gas to commercial and domestic users across utility networks within countries, regions and municipalities.

Regular maintenance of gas distribution systems is essential. Identifying and rectifying gas leaks is also an integral part of any maintenance programme, but it is notoriously difficult in many urban and industrial environments, as the gas pipes may be located underground, overhead, in ceilings, behind walls and bulkheads or in otherwise inaccessible locations such as locked buildings. Until recently, suspected leaks from these pipelines could lead to whole areas being cordoned off until the location of the leak was found.

Precisely because conventional gas detectors – such as those utilising catalytic combustion, flame ionisation or semiconductor technology – are not capable of remote gas detection and are therefore unable to detect gas leaks in hard to access pipelines, there has been a lot of recent research into ways of detecting methane gas remotely.

Remote Detection

Cutting edge technologies are now becoming available which allow the remote detection and identification of leaks with pinpoint accuracy. Hand-held units, for example, can now detect methane at distances of up to 100 metres, while aircraft-mounted systems can identify leaks half a kilometre away. These new technologies are transforming the way natural gas leaks are detected and dealt with.

Remote sensing is achieved using infrared laser absorption spectroscopy. Because methane absorbs a specific wavelength of infrared light, these instruments emit infrared lasers. The laser beam is directed to wherever the leak is suspected, such as a gas pipe or a ceiling. Because some of the light is absorbed by the methane, the light received back provides a measurement of absorption by the gas. A useful feature of these systems is the fact that the laser beam can penetrate transparent surfaces, such as glass or perspex, so it may be possible to test an enclosed space prior to entering it. The detectors measure the average methane gas density between the detector and target. Readings on the handheld units are given in ppm-m (a product of the concentration of methane cloud (ppm) and path length (m)). In this way, methane leaks can be quickly confirmed by pointing a laser beam towards the suspected leak or along a survey line, for example.

An important difference between the new technology and conventional methane detectors is that the new systems measure average methane concentration, rather than detecting methane at a single point – this gives a more accurate indication of the severity of the leak.

Applications for hand-held devices include:

  • Pipeline surveys
  • Gas plant
  • Industrial and commercial property surveys
  • Emergency call out
  • Landfill gas monitoring
  • Road surface survey

Municipal Distribution Networks

The benefits of remote technology for monitoring pipelines in urban settings are now being realised.

The ability of remote detection devices to monitor gas leaks from a distance makes them extremely useful tools in emergencies. Operators can stay away from potentially dangerous leak sources when checking the presence of gas in closed premises or confined spaces as the technology allows them to monitor the situation without actually gaining access. Not only is this process easier and quicker, but it is also safe. Moreover, it is not affected by other gases present in the atmosphere since the detectors are calibrated to only detect methane – therefore there is no danger of getting false signals, which is important in emergency situations.

The principle of remote detection is also applied when inspecting risers (the above-ground pipes carrying gas to the customers’ premises and normally running along the building outside walls). In this case, the operators point the device towards the pipe, following its route; they can do this from ground level, without having to use ladders or access the customers’ properties.

Hazardous Areas

In addition to detecting gas leaks from municipal distribution networks, explosion-proof, ATEX approved devices can be used in Zone 1 hazardous areas such as petrochemical plants, oil refineries, LNG terminals and vessels, as well as certain mining applications.

When inspecting an LNG/LPG underground tank, for example, an explosion-proof device would be required within 7.5 metres of the tank itself and one metre around the safety valve. Operators therefore need to be fully aware of these restrictions and equipped with the appropriate equipment type.

GPS Coordination

Some instruments now allow spot methane readings to be taken at various points around a site – such as an LNG terminal – automatically generating GPS tracking of the measurement readings and locations. This makes return trips for additional investigations far more efficient, while also providing a bona-fide record of confirmed inspection activity – often a prerequisite for regulatory compliance.

Aerial Detection

Moving beyond hand-held devices, there are also remote methane detectors which can be fitted to aircraft and which detect leaks from gas pipelines over hundreds of kilometres. These systems can detect methane levels at concentrations as small as 0.5ppm up to 500 metres away and include a real-time moving map display of gas concentrations as the survey is conducted.

The way these systems work is relatively simple. A remote detector is attached beneath the aircraft’s fuselage (usually a helicopter). As with the handheld device, the unit produces an infrared laser signal, which is deflected by any methane leakage within its path; higher methane levels result in more beam deflection. These systems also utilise GPS, so the pilot can follow a real-time moving map GPS route display of the pipeline, with a real-time display of aircraft path, gas leaks and concentration (in ppm) presented to the crew at all times. An audible alarm can be set for a desired gas concentration, allowing the pilot to approach for closer investigation.

Conclusion

The range of remote methane detection systems is increasing rapidly, with new technologies being developed all the time. All these devices, whether hand-held or fitted to aircraft, allow quick, safe and highly targeted identification of leaks – whether beneath the pavement, in a city or across hundreds of kilometres of Alaskan tundra. This not only helps prevent wasteful and costly emissions – it also ensures personnel working on or near the pipelines are not exposed to unnecessary danger.

Because the use of natural gas is increasing worldwide we foresee rapid technological advances in remote gas detection in applications as diverse as leak survey, transmission integrity, plant and facilities management, agriculture and waste management, as well as process engineering applications such as coke and steel production. Each of these areas have situations where access may be difficult, combined with the need to put personnel protection at the top of the agenda. Opportunities for remote methane detectors are therefore growing all the time.

 

Monitoring and Analysis of Landfill Gases

As recycling becomes more common, use of landfill is reducing, but it is still an important means of waste disposal. For example, 2012-13 figures from Defra (department of the environment, food and rural affairs) for England show that 8.51 million tonnes, or 33.9%, of waste collected by local authorities went to landfill.

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Cross Calibration of Pellistor (Catalytic Flame) Sensors‡

After last week’s comparative levity, this week, I am discussing something rather more serious.

When it comes to detecting hydrocarbons, we often don’t have a cylinder of target gas available to perform a straight calibration, so we use a surrogate gas and cross calibrate. This is a problem because pellistor’s give relative responses to different  flammable gases at different levels. Hence, with a small molecule gas like methane a pellistor is more sensitive and gives a higher reading than a heavy hydrocarbon like kerosene.

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