Archive for the ‘Gas Energy’ Category

Awareness of Oxygen Depletion in Liquid Nitrogen Applications

All I need is the air that I breathe?. Like most living organisms, humans have a few basic requirements for sustaining life ? and sadly beer and curry are actually not on that list! Oxygen is essential for life and our requirements are actually quite specific and relate to the atmosphere that we as a species have developed in. Any depletion of the oxygen level in air must be treated with concern, and as a minimum the concentration in the workplace should be maintained above 19. 5%. Crucially, atmospheres containing less than 18% oxygen are potentially dangerous and suitable protection methods should be adopted (e. g. the use of breathing apparatus). Asphyxiation as a result of oxygen depletion can take place on a gradual or sudden basis, depending upon the extent of the depletion. It is a little known fact that inhalation of a gas containing virtually no oxygen can result in immediate unconsciousness and rapid death. The symptoms associated with oxygen depleted atmospheres are detailed in Table 1. Table 1 – Asphyxia Symptoms for Low Oxygen Levels % Oxygen Content of Air & Signs and Symptoms of Asphyxia 18% – 19. 5% – May affect physical and intellectual performance without person?s knowledge. 15% – 18% – Decreased ability to work strenuously. May impair co-ordination and may induce symptoms in persons with coronary, pulmonary, or circulatory problems. 12% – 15% – Respiration deeper, increased pulse rate, and impaired co-ordination, perception and judgment. 10% – 12% – Further increase in rate and depth of respiration, further increase in pulse rate, performance failure, giddiness, poor judgment, blue lips. 8% – 10% – Mental failure, nausea, vomiting, fainting, ashen face, blue lips. 6% – 8% – Loss of consciousness within a few minutes, resuscitation possible if carried out immediately. 0% – 6% – Loss of consciousness almost immediate, death ensues, brain damage even if rescued. Liquid nitrogen ? the great cryogen Liquid nitrogen (LIN) is used in extensively across the World, particularly for its excellent cryogenic properties. Produced from the liquefaction of air, it is colourless, odourless and exists at temperature of -196oC at atmospheric pressure. Liquid nitrogen is the preferred method of cryogenic storage, for example in the preservation of biological samples, as unlike electrical freezers it relatively cheap to purchase, does not rely on electricity (and is not susceptible to electrical outages) and has low running costs. It is supplied via specialised road tanker into insulated storage vessels, ranging from non-pressurised dewars and desks flasks to pressurised tanks for mobile or static storage. Liquid nitrogen is also very safe under normal usage and many people associate the extreme cold temperature as the main source of risk. However, when Liquid Nitrogen evaporates (e. g. through spillage) it undergoes a large volume expansion as it returns to the gaseous form ? one litre of liquid nitrogen produces approximately 680 litres of nitrogen gas! This expansion ratio will quickly displace the atmosphere within a confined space and can cause oxygen depletion if control measures are not in place. To find out more about Liquid Nitrogen, go to CryoService pages on: Liquid Nitrogen Providing early warning Whilst fully-integrated ?cryorooms? are discussed later, one of the most critical aspects of safety awareness and enhancement in these applications is the correct use of gas detection equipment, in the form of oxygen depletion monitoring A typical oxygen depletion monitor consists of an electrochemical sensor which generates a small electrical signal in proportion to the concentration of oxygen present. This sensor signal is then amplified to display the oxygen level on either a portable or fixed-point instrument. Oxygen sensors are typically calibrated in air (having first been zeroed using 100% nitrogen) so that 20. 9% volume oxygen is displayed in clean-air environments. Oxygen depletion alarms are usually set at 19% and 17% volume. Portable instruments are typically worn on breast pockets (ie within the vicinity of the breathing zone) to provide protection to personnel. Staff working within an area where an oxygen depletion risk exists are trained to evacuate immediately in the event of their portable monitor producing a low oxygen alarm. Fixed-point oxygen monitoring systems utilise one or more oxygen sensors installed in the vicinity of potential nitrogen leak sources (ie near vessels, flanges, valves etc), which are connected to a control panel. The sensors permanently monitor the area, and the control panel displays the gas levels and provides alarms in the event of a sensor reporting a reduced concentration of oxygen. Control panels can also be used to take executive actions such as closing solenoid valves to prevent further nitrogen releases. Fixed systems provide the significant advantage of warning of a reduced level of oxygen before personnel enter an area. To understand more about oxygen depletion system, visit the Crowcon gas detectors site at Crowcon. com Case Study ? ?Workers at one of the UK’s largest vacuum test chambers kept safe with Crowcon gas detectors? To protect workers from the danger of depleted oxygen levels, the Rutherford Appleton Laboratory has recently installed four Crowcon gas detectors and a Gasmaster control panel. The Gasmaster control panel displays oxygen levels in all the testing cleanrooms simultaneously on a large, LCD display, allowing full system status checks at a glance. The Crowcon units are installed in the Assembly Integration and Verification (AIV) Facility’s suite of cleanrooms, where spacecraft and satellite components are subjected to extreme temperature and vacuum conditions. The facility has a number of vacuum chambers and other testing laboratories. The largest vacuum chamber ? one of the biggest in the UK ? is highly versatile and can simulate near-space conditions with temperatures from -196oC to + 150 oC. The chambers are returned to atmospheric pressure by introducing nitrogen gas. It can take up to four hours to return the largest chamber to atmospheric pressure, and if nitrogen leaked out during this time, it could result in rapid oxygen depletion in the laboratory. The oxygen sensors ensure that should this happen, the Gasmaster control panel will instantly inform controllers which detector has been activated with a visual signal such as “Vacuum chamber 1″, as well as activating audible/visual alarm devices. “Our air conditioning system changes the air up to six times an hour so if there ever was a nitrogen leak, the aircon would normally take care of it,” commented technician Dave Rippington. “The Crowcon systems are really in place as part of a ‘belt and braces’ approach, ensuring our workers are safe in the highly unlikely event that there was both a nitrogen leak and the air-con system failed. ” Best practise control measures The main application considered here is biological sample storage within typical research, academic and hospital environments and there are effectively two infrastructures in which this product is used. The first is the purpose-designed ?cryoroom?, a dedicated facility for the storage of preserved samples and the supply of Liquid Nitrogen to them. These have generally undergone extensive design and feature best practise in risk management. Typical features of a dedicated cryoroom are: External storage of Liquid Nitrogen. A transfer pipeline for Liquid Nitrogen into the cryoroom ? this is often referred to as Super Insulated Vacuum Line (SIVL) as it is highly insulated to prevent Liquid Nitrogen boil-off. The use of large cryogenic freezers, generally storing samples in vapour phase (reduces the amount of Liquid Nitrogen contained) with automated temperature control and auto-fill systems. The latter means that personnel do not have to be present when the freezers are being filled; and systems can operate on a time or level basis. An integrated fixed gas detection system, often with multiple sensors and alarms linked to a Business Management System and a safety shut off solenoid for the SIVL line to cut-off the Liquid Nitrogen supply in the event of an oxygen depletion alarm. A ventilation system linked to the gas detection equipment, providing increased throughput on low oxygen levels. A door interlock system that allows escape but prevent access in emergency conditions. Specialised flooring and lifting equipment. An extensive maintenance routine covering all aspects of the system. The second type is where Liquid Nitrogen is used in individual laboratories from small wheeled tanks or from unpressurised dewars. Liquid Nitrogen is generally manually decanted using a hose or transfer device into small aluminium freezers with liquid phase storage. Whilst this arrangement is not as desirable as the purpose-built cryoroom, building infrastructure issues or funding often means that it is the most pragmatic way to operate. Safety can be maximised in these situations by considering the following: Minimise the storage of samples in a laboratory. Many facilities retain samples for archiving purposes that will rarely if ever be used in daily operation. Several private off-site repositories have opened in the UK specifically to assist with this problem. Minimise the amount of Liquid Nitrogen stored in your laboratory. Can the vessels be stored in a suitable outside area, where product can be transferred into a non-pressurised dewar for topping up freezers periodically? The use of a phase separator (a small sintered device) on liquid nitrogen transfer hoses to minimise splashing and resultant evaporation. The use of gas detection to allow early warning of oxygen depletion. Consider the fitment of a ?repeater? or external alarm that is visible outside the laboratory to prevent people entering in emergency conditions. Fixed monitors are preferable to personal monitors as they protect everyone in an area. Ensuring adequate ventilation, through LEV or similar. Remember that cold nitrogen gas is heavier than air and will accumulate in low areas such as pits or gulleys. To find out more about cryoroom and Liquid Nitrogen freezers go to the CryoService pages on Cryogenic Freezers

Seabrook Explosion

seabrook texas

A large chemical plant explosion near Seabrook early this morning sent a gigantic plume of smoke billowing into the air, but there were no serious injuries.

The explosion occurred at an American Acryl facility at 11600 Port Road near old Texas 146 about 8:50 a.m., according to the Seabrook Police Department. A short section of Texas 146 near the blast site was closed in both directions, as is Port Road.

An hour later, firefighters appeared to have the fire out, and no smoke was visible from the charred wreckage at the plant. Two people went to Memorial Hermann Hospital Southeast complaining of discomfort, said Seabrook police Lt. Sean Wright.

Memorial Hermann spokeswoman Jennifer Hart said both were in good condition.

Area residents were asked to shelter in place after the blast, but that recommendation was lifted by 11 a.m. Officials said the blast involved toluene, a toxic substance that can cause nausea and tiredness in low to moderate levels.

However, in a recorded message company said the explosion did not cause a release of the chemical.

Shoreacres Police Officer D. Cantu, who was in the La Porte area at the time, said he heard the blast and turned in time to see “a ball of fire going up into the air.” Reports indicate the blast was heard or felt as far away as Baytown and Pearland.

American Acryl was permitted in 2000 to build a $150 million chemical plant in the Bayport industrial district.

The facility is built on about 65 acres and and includes a 120,000-ton-per-year acrylic acid plant.

Acrylic acid is a key component in many commonly used household and personal care products such as disposable diapers and water-based products for paints, inks and adhesives.

American Acryl was formed in 1997 and is a 50-50 joint venture between NA Industries Inc. and Atofina Chemicals Inc., who are the North American subsidiaries of Nippon Shokubai and Total Fina Elf S.A., respectively.

Businesses Can Save Energy and Cut Expenses with a Nitrogen Generator

It’s not just you and your eco-conscious neighbors who are looking for ways to conserve energy and preserve the environment. The term “carbon footprint” is the new catchword of the day, and businesses are learning that it applies to their own big “shoe” as well.

Saving energy makes sense all around. Businesses that put energy conservation measures in place help preserve the environment, make use of renewable resources, AND save money.

There are plenty of simple ways that businesses can encourage energy conservation, recycling, and environmental awareness, both on an individual and corporate level.

For instance, research shows that recycling an aluminum can save 95 percent of the energy required to make the same amount of aluminum from virgin materials. Producing glass from virgin materials requires 30 percent more energy than producing it from crushed, used glass; recycled paper requires about 60 percent of the energy used to make paper from virgin wood pulp.

If your company has an application or production need for Nitrogen, PSA and Membrane Nitrogen Gas Generators cut down on energy use considerably by completely eliminating the necessity of converting nitrogen into liquid form for transportation and delivery. Making liquid Nitrogen requires that Nitrogen gas be pressurized and cooled to very low temperatures, a process that involves a large amount of energy.

Nitrogen generators cut out that process entirely, since all you need is a source of compressed air – an infinitely renewable resource – to make Nitrogen gas. As the air is fed into the generator, oxygen and other molecules are trapped, then vented out while the Nitrogen is pushed into a storage tank.

Nitrogen Gas Generators are a simpler, “greener”, and far more cost-effective way to meet your Nitrogen needs.

A Nitrogen Generator “borrows” Nitrogen from the air for your application. It then goes right back out to the air where it belongs, without dragging along dirt or contaminants with it, or creating any other particulate or nasty substance to alter the world around us. Nitrogen Generators also cut down on huge tankers hauling liquid down our nation’s highways. Plus, Nitrogen comprises more than 78% of the air, so it is an infinitely renewable resource.

And what will you do with the money you save when you end your gas contract and make your own Nitrogen with a Nitrogen Generator? You might look into even more opportunities to be greener with your business. Corporate tax incentives for energy efficient lighting, building insulation, renewable energy resources and many more energy and cost saving technologies have been in place for several years, and some have been extended this year. Considering some “green” modifications with the money you no longer pay the gas company might make those savings go even farther with energy conscious tax breaks.

Investing in a Nitrogen Generator will result in a positive return on investment for both your business and the world around you. Consider making this change today.

What is Liquefied Natural Gas?

Liquefied natural gas, often abbreviated LNG, is simply the liquid form of the natural gas commonly used for heating homes, cooking, and fueling electrical power plants, among other uses. As you may know, natural gas is a fossil fuel that occurs naturally deep within the earth, most often accompanying deposits of oil but sometimes occurring alone. Liquefied natural gas is formed through the process of liquefaction, in which heat is removed from the natural gas and it is converted to a lightweight liquid.

Natural gas is primarily composed of methane, though traces of other elements and compounds, including water, may also be found within it. Some substances, such as water, must be removed before liquefaction because the extremely low temperature required for the process causes certain such substances to form solids. Liquefied natural gas is colorless, odorless, and produces low emissions when burned as compared to other fossil fuels.

Converting natural gas into liquefied natural gas allows for efficient transportation and storage of the resource. When natural gas is converted to LNG, its volume is significantly decreased, facilitating efficient transport by water over the long distances between continents, thus allowing for the cost efficient import and export of this valuable resource. When a specifically designed LNG carrying ocean vessel delivers its cargo to one of the import terminals in the United States, the liquefied natural gas is stored in special storage tanks until it is time for it to be converted back to a gas and delivered via pipeline to natural gas consumers. Companies providing electric power and natural gas may also ?stock up? on LNG when prices are low for use during peak demand times, a technique known as peak shaving.

The demand for natural gas in the United States is widely believed to be increasing at a higher rate than supply at the current level can fulfill. The industry is complex in that numerous levels of the supply chain must align in order to be economical. The vessels that transport liquefied natural gas, import stations where such vessels deliver the gas and the facilities which perform the process of liquefaction as well as converting the liquid back to a gas are extremely specialized and must strike a balance in order to ensure that the process is economical and efficient. Locating and extracting natural gas from within the earth, converting it into a liquid state, safely transporting it via pipeline and or ocean vessels, and converting it back into its gaseous state in an economical way is important to maintaining manageable prices for consumers.

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