May 24, 2010

Calibration Got You Down?

Hello. My name is Dave Joseph and I’m industry manager for the chemical, pulp and paper, and metals and mining industries at Rosemount Analytical. I want to share some news about how you can improve pH sensor maintenance and make your life easier.

If you see someone carrying a plastic tray with small multicolored bottles of liquid at work, there’s a good chance they’re going off to work on pH sensors (unless you happen to be in a bar or a plane…).  The standard calibration for pH sensors is to immerse the sensor in two different buffers to prove that the sensor works and to calibrate the sensor’s response. This works great but may not be too convenient if the sensor is located where it’s really hot or wet or noisy or, well, you get the point. Our new smart sensors have a chip inside that stores all calibration data, which allows the sensor to come pre-calibrated from the factory. Subsequent calibrations (as needed) can be done in a lab or workshop and the sensor is easily moved from place to place since the cable connection is a VP quick disconnect. Pull sensors from the field, calibrate them in the lab, and return them to service on the next visit.

Smart sensors will be available on nearly all our pH models and will replace the preamplifier that is typically required to process the mV signal from the pH sensor. The latest analyzers, including models 1056, 1057 and 6081, are smart-aware, but the beauty of the smart design is backwards compatibility — other analyzers can use the smart sensors to measure pH just like before, but when connected to a newer analyzer, the additional smart features are activated.

Early adopters have liked the smart sensors so much that we offer a benchtop calibrator that incorporates a 1056 analyzer and has everything you need for periodic calibration of sensors.

Next time, I’ll talk about how the smart sensors help you manage sensor diagnostics and schedule periodic maintenance.

May 11, 2010

Reducing Total Cost-of-Ownership in Gas Chromatographs

Daniel Benitez, Rosemount Analytical vice president of marketing for analyzers and solutions, recently offered some tips for reducing the total cost of ownership in gas chromatographs. The primary areas to look at are the type of oven and shelter you select. 

Oven Options 

New technologies in airless ovens offer a more flexible, cost-saving choice over traditional air-bath ovens. The airless oven enables the GCs to perform well in environments with changing temperatures. Air-bath ovens rely on plant or compressed air to heat the analytical oven to a constant and optimal temperature – which means a temperature above the dewpoint and optimized for component separation. Airless ovens don’t require expensive air sources, and consequently, consume less power. This means that the GC can be mounted closer to the sample point, reducing sample line run lengths, and ultimately, saving money, reducing the volume of sample required, and in installations requiring heated lines, reducing utility requirements. In fact, an airless oven can reduce overall operating costs by up to 70 percent. In addition, they take up less space than air baths. Reduced space and energy requirements make them well suited for a number of process applications. 

Shelter Options 

Analyzer shelters can be one of the most substantial expenses associated with your analytical solution. There are three choices – analyzer house, a three-sided shelter or sunshield, and a field-mounted gas chromatograph with no shelter. 

  • Analyzer House — An analyzer house is ideal for plants in extremely hot or cold climates and where the safety and comfort of the employees is a key consideration. Complete analyzer houses are also the most costly option, however. In addition to an expensive enclosed structure, there are significant hidden costs associated with an analyzer house, including high shipping fees, extensive cabling and tray requirements, increased assembly and installation costs, high maintenance fees, more required spare parts, and high utility and power consumption. Because an analyzer house can potentially entrap hazardous gases, additional capital expenses, including hazardous area compliance, safety systems, and fire and gas detection systems are often required.
  • Three-sided shelters or sunshields — Because they are designed with an open structure, three-sided shelters and sunshields have no risk of entrapment of hazardous gases, and as such, offer a lower cost solution by not requiring HVAC equipment, a safety system, or fire and gas detection systems. Also, shipping expenses are significantly less because a three-sided shelter weighs considerably less than an analyzer house. There will still be capital expenses associated with cabling and trays, assembly and installation, and maintenance and spare parts, but it will be lower than the capital expenses associated with an analyzer house.
  • Field-mounted solution (no shelter) — Field-mounted gas chromatographs that offer a flameproof and weatherproof enclosure provide the greatest overall savings. There are no shelter-related expenses, in most cases, the only cabling that is required is the cabling that comes with the gas chromatograph, and shipping expenses are very low.

Regardless of what kind of analyzer shelter you select for your process application, one tip for reducing the total cost of ownership is to re-evaluate the upgrade path. Rather than replacing the entire analyzer house when a new chromatograph is necessary, you can instead install a new non-temperature-sensitive field-mountable gas chromatograph into your existing shelters. This substantially reduces costs and implementation expenses. 

The right analyzer is always unique to your application, but it can have a tremendous impact on capital expenses and long-term operating costs. By considering these options, you can greatly impact the bottom line.