Blogs listed by tag: H2

Xgard Type 3: The mV Advantage

Xgard Type 3 is the ideal solution for detecting lighter-than-air flammable gases such as methane and hydrogen. Detectors in such applications usually have to be mounted high-up in roof spaces or above equipment where access for calibration and maintenance is  likely to present problems.

Gas detectors require calibration (usually every six months) and sensors may need to be replaced every 3-5 years. These activities usually require direct access to the detector to make adjustments and replace parts. National regulations such as the ‘UK Work at Height Regulations 2005’ stipulate safe working practices when working on equipment at height, and compliance usually requires the use of scaffolding or mobile ‘cherry pickers’ which entails significant cost and disruption on-site.

The advantage of mV pellistor type detectors

The terms ‘mV’ and ‘4-20mA’ describe the type of signal which is transmitted through the cable between the gas detector and the control system (for example a Crowcon Gasmaster). Calibration of  4-20mA detector (e.g. Xgard Type 5) entails removing the lid, and zeroing/calibrating the amplifier using a meter, test-points and potentiometers. Even more sophisticated detectors with a display and non-intrusive calibration still require direct access to operate the menu system using a magnet in order to perform calibration.

Xgard Type 3 is a mV pellistor-based detector which has no internal electronics (i.e. no amplifier); just terminals to connect via three wires to the control system (e.g. Gasmaster). Commissioning simply entails measuring the ‘head voltage’ at the detector terminals, and performing zero and calibration adjustments at the Gasmaster input module. Ongoing 6-monthly calibrations are then performed by remotely applying gas (via a ‘spray deflector’ or ‘collector cone’ accessory), and any necessary adjustments are made at ground level via the control system input module.

Hence once commissioned, mV pellistor type detectors do not need to be accessed until the sensor needs replacing; usually 3-5 years after installation. The routine need for expensive access equipment; scaffolding or cherry-pickers in thus avoided.

Xgard Type 3 can be directly connected to Gasmaster and Gasmonitor systems, and to Vortex via an ‘Accessory Enclosure’ accessory which converts the mV signals to 4-20mA.

Remote calibration of a mV pellistor type detector
Remote calibration of a mV pellistor type detector.
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The Importance of Gas Detection in the Power Industry

The energy industry is the very backbone of our industrial and domestic worlds, supplying essential energy to industrial, manufacturing, commercial and residential customers around the globe. With the inclusion of fossil fuel industries (petroleum, coal, LNG); electricity generation, distribution and sales; nuclear energy and renewable energy, the power generation sector is essential in supporting the increasing demand for power from emerging countries and an increasing world population.

Gas Hazards in Power Sector

Gas detection systems have been installed extensively in the power industry to minimise potential consequence through the detection of gas exposure with those working within this industry are exposed to a variation of power plant gas hazards.

Carbon monoxide

The transport and pulverisation of coal poses a high risk of combustion. Fine coal dust becomes suspended in air and highly explosive. The smallest spark, for example from plant equipment, can ignite the dust cloud and cause an explosion that sweeps up more dust, which explodes in turn, and so on in a chain reaction. Coal power plants now require combustible dust certification, in addition to hazardous gas certification.

Coal power plants generate large volumes of carbon monoxide (CO) which is both highly toxic and flammable and must be accurately monitored. A toxic component of incomplete combustion, CO comes from boiler casing leaks and smouldering coal. It is vital to monitor CO in coal tunnels, bunkers, hoppers and tipper rooms, along with infrared-type flammable gas detection to detect pre-fire conditions.

Hydrogen

With hydrogen fuel cells gaining popularity as alternatives to fossil fuel, it is important to be aware of the dangers of hydrogen. Like all fuels, hydrogen is highly flammable and if it leaks there is real risk of fire. Hydrogen burns with a pale blue, almost invisible, flame that can cause serious injuries and severe equipment damage. Therefore, hydrogen must be monitored, to prevent seal-oil system fires, unscheduled shutdowns and to protect personnel from fire.

In addition, power plants must have back-up batteries, to ensure the continued functioning of critical control systems in cases of power outage. Battery rooms generate considerable hydrogen, and monitoring is often carried out in conjunction with ventilation. Traditional lead acid batteries produce hydrogen when they are being charged. These batteries are normally charged together, sometimes in the same room or area, which can generate an explosion risk, especially if the room is not properly ventilated.

Confined Space Entry

Confined space entry (CSE) is often considered to be a dangerous type of work performed in power generation. It is therefore important that the entry is strictly controlled and detailed precautions are taken. Lack of oxygen, toxic and flammable gases are risks that can occur during work in confined spaces, which should never be considered as simple or routine. However, the hazards of working in confined spaces can be predicted, monitored, and mitigated through the use of portable gas detection devices. Confined Spaces Regulations 1997. Approved Code of Practice, Regulations and guidance is for employees that work in Confined Spaces, those who employ or train such people and those who represent them.

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, 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, XgardIQ 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 power industry our panels include Vortex and Gasmonitor.

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

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An Introduction to the Oil and Gas Industry 

The oil and gas industry is one of the biggest industries in the world, making a significant contribution to the global economy. This vast sector is often separated into three main sectors: upstream, midstream and downstream. Each sector comes with their own unique gas hazards. 

Upstream

The upstream sector of the oil and gas industry, sometimes referred to as exploration and production (or E&P), is concerned with locating sites for oil and gas extraction the subsequent drilling, recovery and production of crude oil and natural gas. Oil and gas production is an incredibly capital-intensive industry, requiring the use of expensive machinery equipment as well as highly skilled workers. The upstream sector is wide-ranging, encompassing both onshore and offshore drilling operations. 

The major gas hazard encountered in upstream oil and gas is hydrogen sulphide (H2S), a colourless gas known by its distinct rotten egg like smell. H2S is a highly toxic, flammable gas which can have harmful effects on our health, leading to loss of consciousness and even death at high levels. 

Crowcon’s solution for hydrogen sulphide detection comes in the form of the XgardIQ, an intelligent gas detector which increases safety by minimising the time operators must spend in hazardous areas. XgardIQ is available with high-temperature H2S sensor, specifically designed for the harsh environments of the Middle East. 

Midstream

The midstream sector of the oil and gas industry encompasses the storage, transportation and processing of crude oil and natural gas. The transportation of crude oil and natural gas is done by both land and sea with large volumes transported in tankers and marine vessels. On land, transportation methods used are tankers and pipelines. Challenges within the midstream sector include but are not limited to maintaining the integrity of storage and transportation vessels and protecting workers involved in cleaning, purging and filling activities. 

Monitoring of storage tanks is essential to ensure the safety of workers and machinery. 

Downstream

The downstream sector refers to the refining and processing of natural gas and crude oil and the distribution of finished products. This is the stage of the process where these raw materials are transformed into products which are used for a variety of purposes such as fuelling vehicles and heating homes.  

The refining process for crude oil is generally split into three basic steps: separation, conversion and treatment. Natural gas processing involves separating the various hydrocarbons and fluids to produce ‘pipeline quality’ gas. 

The gas hazards which are typical within the downstream sector are hydrogen sulphide, sulphur dioxide, hydrogen and a wide range of toxic gases. Crowcon’s Xgard and Xgard Bright fixed detectors both offer a wide range of sensor options to cover all the gas hazards present in this industry. Xgard Bright is also available with the next generation MPS™ sensor, for the detection of over 15 flammable gases in one detector. Also available are both single and multi-gas personal monitors to ensure workers safety in these potentially hazardous environments. These include the Gas-Pro and T4x, with Gas-Pro providing 5 gas support in a compact and rugged solution.

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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.

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What do you need to know about Hydrogen?

Hydrogen, alongside other renewables and natural gas has an increasingly vital role to play in the clean energy landscape. Hydrogen is found in various things including light, water, air, plants, and animals, however, is often combined with other chemicals, the most familiar combination is with oxygen to make water.

What is Hydrogen and what are its benefits?

Historically, Hydrogen Gas has been used as a component for rocket fuel as well as in gas turbines to produce electricity or to burn to run combustion engines for the power generation. In the Oil and Gas Industry, excess hydrogen from the catalytic reforming of naphtha has been used as fuel for other unit operations.

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. This is done by separating it from other elements and collecting the vapour. Electrolysis is completed by taking liquid usually water and separating this from the chemicals found within it. In water the hydrogen and oxygen molecules separate leaving two bonds of hydrogen and one bond of oxygen. The hydrogen atoms form a gas which is captured and stored until required, the oxygen atoms are released into the air as there is no further use. The hydrogen gas that is produced leaves no damaging impact on the environment, leading to many experts believing this is the future.

Why Hydrogen is seen as a cleaner future.

In order to make energy a fuel that is a chemical is burnt. This process usually means chemical bonds are broken and combined with oxygen. Traditionally, Methane gas has been the natural gas of choice with 85% of homes and 40% of the UK’s electricity depending on gas. Methane was seen as a cleaner gas compared to coal, however, when its burnt carbon dioxide is produced as a waste product thereby contributing to climate change. Hydrogen Gas when burnt only produces water vapour as a waste product, this being already a natural resource.

The difference between blue hydrogen and green hydrogen.

Blue hydrogen is produced from non-renewable energy sources, through two methods either Steam or Autothermal. Steam Methane reformation is the most common when producing hydrogen in bulk. This method uses a reformer which produces steam at a high temperature and pressure and is combined with methane and a nickel catalyst to produce hydrogen and carbon monoxide. Autothermal reforming uses the same process however, with oxygen and carbon dioxide. Both methods produce carbon as a by-product.

Green hydrogen is produced using electricity to power an electrolyser that separates hydrogen from the water molecule producing oxygen as a by-product. It also allows for excess electricity to electrolysis to create hydrogen gas that can be stored for the future.

The characteristics that hydrogen presents, has set a precedence for the future of energy. The UK Government have seen this a way forward for a greener way of living and have set a target for a thriving hydrogen economy by 2030. Whilst Japan, South Korea and China are on course to make significant progress in hydrogen development with targets set to match the UK for 2030. Similarly, the European Commission have presented a hydrogen strategy in which hydrogen could provide for 24% of the world’s energy by 2050.

For more information, visit our industry page and have a look at some of our other hydrogen resources:

The Dangers of Hydrogen

Green Hydrogen – An Overview

Blue Hydrogen – An Overview

Xgard Bright MPS provides hydrogen detection in energy storage application

 

 

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Cross sensitivity of toxic sensors: Chris investigates the gases that the sensor is exposed to

Working in Technical Support, one of the most common questions from customers is for bespoke configurations of toxic gas sensors. This frequently leads to an investigation into the cross sensitivity of the different gases that the sensor will be exposed to.

Cross sensitivity responses will vary from sensor type to sensor type, and suppliers often express the cross sensitivity in percentages while others will specify in actual parts-per-million (ppm) levels.

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