Hello, this is Mauricio Romero, Latin American Business Development Manager for Emerson Process Management, Net Safety. In this blog post I’m going to outline challenges related to flame and gas detection within Geothermal power plants. Geothermal energy is a nonconventional supply which has many advantages. It is completely renewable, requiring only naturally present water and is continually replenished by heat generated from the earth’s core. There are very few, if any, by-products from the resulting steam, so the process is very clean and is of course a completely domestic energy source. With the cost and efficiencies associated with geothermal energy production beginning to match that of traditional power sources, more utilities and other companies are finding ways to take advantage of this resource.

Perhaps one of its few limitations is that the steam generated in many cases cannot be used as the primary driver for turbines, because it is not hot enough to flash on its own and water droplets can cause serious damage to mechanical components of the turbine. One good way to resolve this is by using a binary cycle concept design that uses hot water from the geothermal sources and a fluid with a much lower boiling point than water that is heated by the geothermal source – the steam from this liquid is then used to drive the turbine.

One of the best options for this application is pentane, which has a much lower boiling point than water. One huge disadvantage is that it’s extremely explosive, and even more so when converted into an absolute gaseous state.

In order to create a safe environment a reliable detection solution must be put in place to monitor the plant area for any potential pentane gas leak that can develop into an very serious condition if ignition was to take place. Normally these plants are located in remote areas, so detection technology must be very robust with minimum maintenance requirements, and power consumption has to be well monitored in order to avoid wasting the valuable energy generated onsite.

Installing Emerson Process Management, Net Safety detection solutions has proven to be an effective way to monitor potential hazards in this type of installation. Either catalytic bead sensor or infrared sensor technology can be used to monitor gas leaks of hot pentane, which happens to be a very heavy gas, making it extremely dangerous. Some alarms can be configured to provide early warning of dangerous concentrations of pentane in the environment, which can be used to alert personnel by means of signaling devices such as strobes or horns. This early detection will allow plant operators to proceed with effective measures that can range from isolating the environment, inspecting the area to visualizing points of pentane leakage. If a gas release results in a fire, optical flame detectors such as UV/IR or IR3 technology will be ready to respond instantly. Fast and accurate notification from flame detectors will also allow personnel to proceed with effective emergency response, potentially from remote locations, so time is of the essence in these circumstances. It may involve releasing of extinguishing systems to protect property, partial or total shutdown of the plant to minimize consequences, and evacuation of any personnel in the facility.

Net Safety detection technologies have proven to be an optimum solution overall in this application, due to a combination of highly robust construction that can resist the most challenging plant conditions and extreme environments, the lowest possible power consumption for fixed detection devices, with intuitive designs and special features that make Net Safety instruments highly reliable, user friendly and low maintenance.

Ensuring safety for personnel and protection of facilities and equipment is a top priority for all industrial plants. A critical element of this is the effective detection of dangerous flammable and toxic gases and vapors and their potential ignition. However, building an effective safety monitoring solution is a complex task as there is no single system or technology that would be the solution for every plant. There are several fundamental choices available in detection technologies. Jonathan Saint from Emerson Process Management, Net Safety recently published an article with Facility Safety Management that addressed the available options and how to build a solution that works for your plant while saving lives, property and dollars.

An effective solution requires three levels of detection. Safety systems that deploy a diverse range of safety technologies can counteract the serious impacts of gas leaks and the potential for fire and explosions. The article entitled Three Levels of Detection Safety Monitoring: Combining Technologies for Reliable Results addresses the different types of gas and flame detectors, including point type, line of sight, ultrasonic and flame detectors, and their strengths and weaknesses and how to build an optimal solution using an effective combination of these. Read the full article HERE. Following is an excerpt:

Safety systems that deploy a diverse range of detection technologies can counteract the serious impacts of gas leaks and potential for fire and explosions. A combination of ultrasonic leak detectors, fixed gas monitors and flame detectors, is particularly effective because they’re complementary and cover the three detection defense levels.

The first stage is the immediate leak stage, which has the greatest opportunity for fast and effective mitigation; the second is during the gas cloud formation or accumulation stage, which is a very serious safety condition; and the third is during the ignition state, which can be catastrophic.

Ultrasonic detectors are often installed outdoors to cover wide areas with challenging detection conditions. Point detectors should be installed at or near known high-risk gas leakage points or accumulation areas to provide information on the level of gas present in these areas. Open-path gas detection systems are more effective at plant or process area boundaries. They monitor the plant perimeter and provide an indication of overall gas cloud movement in and out of the facility.

The movement of gas clouds throughout the facility is tracked by monitoring the output signals of all the gas detectors within the safety system. Optical flame detectors monitor wide areas for IR or UV energy related to the ignition of a gas source and provide instant alarm condition back to notification and mitigation systems.

A variety of challenging factors affect the performance of these technologies; location (indoors/outdoors); air flow; gas properties (type, density, buoyancy); environmental conditions like temperature and humidity; background conditions (false alarm sources); and obstruction. Best practices for each application will be different, but it’s critical to perform proper HAZOP analysis and identify the sequence of events leading up to an accident.

Every safety engineer that is committed to safeguarding personnel, plant and productivity, and employing a system that provide comprehensive, tiered coverage can yield optimal results before an escalated incident occurs.

To read the full article, click HERE.

Are you providing the optimal safety coverage within your applications?

Hi everyone. I’m Larry McGee and today I want to talk about a significant development in optical flame detection. Optical flame detectors have historically been fitted with a visual integrity (VI) test feature in order to detect the presence of accumulated material on the lens that would prevent the device from detecting flame – obviously a pretty critical alarm.

Most of the principle VI schemes have employed an internal light source that projects a beam through the lens and into a metal reflector from which the beam is reflected back through the lens and onto the primary sensor where it verifies the integrity of the optical path – maybe! Problems arise because the reflectivity of the metal reflector can be compromised by accumulations of airborne materials and corrosion, thus, the reflector must be maintained on a regular basis. In addition, the lens can have distributed deposits of material that actually block flame signals, but allow the test beam to pass through normally giving a false impression of integrity. Another known issue occurs when reflectors become misaligned and the beam bouncing back to the sensor actually misses, creating a fault condition.

Net Safety's Phoenix Triple IR Flame Detector

The solution to the first issue, with regard to maintaining reflectors for the purpose of visual integrity testing, comes from the technology developed by Net Safety. Our Triple Infrared (IR) detectors employ a system of visual integrity testing that does not use external metal reflectors, greatly reducing VI faults that are often caused by problems with metallic reflectors. The Net Safety technology involves three beams of multi-wavelength infrared energy that are directed through the lens and reflected off the front surface of the lens and back onto the sensing elements. This reflection is caused by the difference in refractive index at the face of the lens where the sapphire lens material ends and atmosphere begins. The amount of energy reflected from a clean, IR transparent lens is known and measured during each VI test cycle. When material that reflects infrared energy (which can obscure the passage of infrared energy into the sensor and reduce its flame detection sensitivity) is deposited on a lens, there is an increase in the amount of energy reflected back into the sensors. This increase in reflected energy is detected and, at a predetermined level, causes the VI fault to trip. With this unique technology we completely eliminate the external reflector from the VI process. This makes verifying optical integrity much more resistant to the VI fault condition, whether by obstruction or reflector misalignment.

In practice, particularly in the oil and gas industry, it is rare to find accumulations of material on the sapphire lens that will block the flame detection capability of the Net Safety Triple IR flame detector. This is in stark contrast to an ultraviolet (UV) flame detector where even a thin, invisible film of oil will fully obscure the flame detector. The materials present in these facilities are predominantly hydrocarbon based materials which are substantially transparent to the wavelengths of infrared energy that are detected and analyzed to identify flame in the detector’s field of view. Testing has revealed that a 1 to 2mm layer of thick, black, petroleum based material has little effect on the flame detection capabilities of the IR instrument. While such a coating is startlingly obvious to the human eye and should be removed as a matter of course during routine maintenance, it has little effect on IR flame detection and hence does not trigger the VI fault condition. While many materials that typically occur in industrial applications, and that could be expected to coat the lens of a standard flame detector, have been tested, none have been found which will substantially obscure flame detection and not be detected by this advanced Triple IR VI verification technology.

Thank you so much for visiting the blog. If you have questions on any aspects of fire or flame detection technology, please leave me a comment here.

Hi everyone. I’m Xavier D’souza from Net Safety and I’d like to tell you about an interesting safety challenge that occurred at a semiconductor manufacturing plant that could have implications for your industrial environment.

The company is a multi-national semiconductor manufacturer that wanted to significantly reduce the risk of a catastrophic event in a wafer manufacturing plant that is very close to a nearby town. The challenge they presented was to assure no risk of an uncontrollable fire by means of a system that could provide reliable detection and mitigation within 90 seconds or less. They needed fast accurate detection in a complex outdoor area monitoring for the presence of invisible Silane flame. Silane Gas (SiH4) is an extremely volatile and toxic gas which can spontaneously ignite on contact with air without any external ignition source, and is almost invisible to the human eye (similar to hydrogen [H2] flame). Silane combustion products, OH and H₂O, are responsible for most of the Silane flame emission in the UV (below 0.3 microns) and near IR (2.7 microns) spectral bands.

Net Safety offered our UV/IRS-A-H2-SS-X for this application, the detector has a 130^o Horizontal and 95^o Vertical FOV and its sensors are fine tuned to the wavelengths produced by Silane flame. We backed up the product performance claims using the data provided by the South West Research Institute which independently tested the flame detector for Silane & Hydrogen Flame. The report produced confirmed that the Net Safety UV/IR H2 flame detector will detect Silane flame in < 2 seconds.

Net Safety worked with our integrator in Italy to provide a SIL 2 approved panel with our detectors, which have their own independent exida SIL 2 rating report.

After successful completion of installation, the integrator carried out performance testing. The time required to create a foam height of 1mts from the point of fire detection was < 90 seconds – this objective was achieved.

Whether you are monitoring for Silane or hydrogen in your plant, finding a detection system fine tuned to the appropriate wavelength will be one key factor to your success.

Xavier D’souza here. In the past customers used conventional LED’s, typically Red color Seven Segment types. We all remember in the 80’s this was the only way to display, however, when customers’ needs became more complex and demanding we saw the advent of LCD (Liquid Crystal Display). This was immediately followed by the backlit displays as it was at times difficult to see the displays, especially in direct sunlight. Today, with the advent of newer technologies, both LCD’s and LED’s have taken a quantum leap and in the last couple of years the market has been increasingly flooded with commercial products using the latest Organic Light Emitting Diodes (OLED’s) and LCD displays.

A typical OLED display is a layer of organic material or polymer between two electrodes, and depending upon the type of organic material used, the color of light will be emitted upon excitation of electrical voltage. Significant improvement in semiconductor technologies has seen the return of the LED’s in the form of OLED, or the Organic LED, with major advantages over its predecessor and other display technologies currently on the market which has many leading manufacturers looking at them again.

Primary benefits include:

• Ability to withstand lower temperatures – Typically, industrial-designed OLED’s can withstand -55^o C, whereas LCD displays can crystallize and leak at these low temperatures. We are seeing newer applications, especially in Arctic drilling, where customers are looking for products to meet a 60^o C requirement and this could be an interesting choice for display.
• Low power consumption – Today we see gadgets all around us – be it the iPad, iPhone, TV, PVR/DVR, etc. – and energy consumption and costs are increasing. Moreover many more devices are being powered in industrial, residential, advertisement media, etc., and it is important to conserve energy to maintain a greener and environment-friendly planet. Low power consumption will go a long way in achieving this goal, moreover these displays do not require backlight thereby further saving power consumption.
• Wider viewing angles and increased brightness makes the display visible even in bright light – this offers a higher contrast and true black color. Customers are demanding higher resolution and true color picture OLED’s due to their higher brightness, making them capable of achieving incredible true-life pictures.
• In order for an LCD to achieve the same level of brightness as OLED it must have a “backlight.” The typical backlight of an LCD, which is an LED or CCFL, typically has a life span of 30,000 to 60,000 hours, which gives it a maximum life span of less than seven years. The OLED display utilized by Net Safety Monitoring with our proprietary screen saver technology has an expected life span of 20 years, even when installed in extreme applications.
• As the world has increasingly moved to a digitally transmitted signal from the hitherto analogue signal, customers are increasingly phasing out their outdated tube-based sets and their power-hungry plasma sets. The volume sales increase will lead to lower prices and vice versa.
• OLED can be manufactured on flexible surfaces, so the displays no longer have to be on a flat screen. It will be possible to mount the display rolled up or in a circular manner, giving designers a new dimension to design newer products with fresh ideas that can challenge the way we have looked at displays. Moreover, the displays can be made very thin, thereby saving volume and weight, giving the product a more refreshing look and reducing shipping & packing costs. A Japanese company is looking to make T-shirts with an OLED display that would be fun to wear and others to watch.

MILLENNIUM II GAS DETECTOR – Superior Display Capabilities Through OLED Technology
Net Safety Monitoring utilizes an OLED display in our Millennium II Series of gas detection products. This display consists of three full lines of information, with 16 alpha-numeric characters per line, for a total of 48 visible characters on the display. This allows for a wide range of information to be simultaneously displayed and effectively communicated in multiple languages, while being easily read in any lighting condition. This large display combined with the other performance advantages associated with OLED displays makes the Millennium II the preferred choice among operators in the field. To learn more about the Millennium II gas detection package and it’s other advanced features, visit www.net-safety.com/millennium2.