CG1212-bridge

Modular Still Matters

Dec. 3, 2012
The Process Analyzer Industry and One of Its Largest User Communities Must Get Away from Building "Steel Copies of Wooden Bridges"
Author

Robert E. Sherman, Valero Energy Corp. Email: [email protected]

"When man invented steel, he did not build steel copies of wooden bridges." — Ayn Rand  From the mid-1940s through the mid-1990s, process analyzers were two- to six- cubic-foot devices, "wooden bridges," if you will. In the late 1990s, Siemens introduced the MicroSAM gas chromatograph (www.usa.siemens.com/pa) to the European market and in 2004 to the North American market, as well as the dual-analytic chassis/single-enclosure spectrophotometer, the Ultramat 23. Suddenly, process analyzers were available in one to two cubic-foot devices (perhaps "steel copies" of those "wooden bridges"?). Other major analyzer manufacturers also introduced spectrophotometers offering this format around that same time. Only one other manufacturer has seen fit to offer a miniaturized process gas chromatograph to the hydrocarbon processing and chemical processing industries. This unit is the Calidas micro gas chromatograph by Falcon Analytical.

In 2002, a group of hydrocarbon processing industry (HPI) and chemical processing industry (CPI) process analyzer personnel gathered and defined ANSI/ISA 76.00.02 (2002), which is generally referred to as the New Sampling and Sensor Initiative (NeSSI), Generation I. It defined a "universal mechanical format" for process analyzer "modular" sample conditioning system components. The process analyzer industry had entered the era of two- to six-cubic inch devices.

This group also defined NeSSI, Generation II (ConnI), as a Universal Connectivity Instrumentation Format for electrical data exchange and component control between process analyzer modular sample conditioning system components.

The process analyzer industry at this point in NeSSI development ran headlong into proprietary systems that channel purchases to a single supplier rather than systems for the universal advancement of the industry. For example, open standard formats are CANBus (IEEE 1451.6) or Modbus (ISA SP100.11a);  i-squared-C was adapted to a Siemens' proprietary version of this universal open standard.

Finally, the NeSSI group defined NeSSI, Generation III (AnNIE), as a Universal Analytical NeSSI Instrumentation Equipment Hardware Format, where the footprint is NeSSI Gen I; the connectivity is NeSSI Gen II; the analytical engine is miniaturized to fit within a 1.50-inch width by multiples of 1.50-inch length and, within reason, unlimited height (NeSSI Gen III); and the analytical performance is maximized by utilization of laser analytical light sources and ASIC PDA (1024 photo diode array) or other miniaturized analytical detectors. Examples include H2scan for a hydrogen-specific analyzer and TOC Systems for a component-addressable non-dispersive infrared (NDIR) spectrophotometer.

The process analyzer industry and one of its largest user communities (HPI/CPI) absolutely must get away from building "steel copies of wooden bridges." In this case, they must get away from building $250,000, NEC/NFPA explosion-proof, climate-controlled 8 ft x 10 ft x 9 ft analyzer shelters to house $25,000,  0.5 ft x 0.5 ft x 1.0 ft process analyzers.

The HPI/CPI communities must provide financial support for the NeSSI generation of process analytical equipment!

The operational model of the HPI/CPI process analyzer system must change. It must evolve from using a relatively expensive, infrastructure-intensive (explosion-proof, climate-controlled, walk-in) shelter/building to a relatively inexpensive integrated infrastructure (NeSSI-format, intrinsically safe, climate-adapted, at-line, 1.0 ft x 1.0 ft x 1.5 ft enclosure process analyzer system).

The maintenance model in this inexpensive integrated infrastructure field application would be an identical, relatively inexpensive NeSSI system available from the analyzer shop as a hot-spare, total-field substitution.

A multi-national refiner considered the NeSSI format and maintenance model for a large chemical plant expansion in Singapore (circa 2007), but ended up only using NeSSI Gen I (basic hardware items in  a 1.50-in. x 1.50-in. footprint) in its process analyzer systems for this major expansion project.

Why was this decision made? In this era of high technology devices, ultra-communication capability and Sarbanes-Oxley accounting principles. this decision came down to the classic conundrum of "the chicken or the egg." If this refiner  went with "the chicken," here being the process analyzer modular sample conditioning system components (Gen I) and the electrical data exchange and component control between process analyzer modular sample conditioning system components (Gen II), would there be future nourishment ("the egg")?

It managed its risk by applying NeSSI Gen I components. At this point in time, there were (and currently are) three major manufacturers producing NeSSI modular substrate basic  (Gen I) components—Circor, Parker and Swagelok —and using classic pressure and flow indication devices to populate the data generation function for control of these many (~400) process analytical systems.

The entire HPI/CPI missed a crucial tipping point with the loss of momentum to use NeSSI Gen II connectivity and NeSSI Gen III pressure and flow indication and control devices. There was a six-month window where this connectivity and component development was in beta test applications, but this refiner could not accept the risk that NeSSI Gen II and Gen III would fail to reach critical mass in time for this very important expansion project to move forward smoothly within its return-on-investment schedule.

Some enlightened HPI/CPI customers were making use of classic proportion process analyzers with NeSSI Gen I sample conditioning systems, NeSSI Gen II data exchange/component control systems, and NeSSI Gen III digital bus flow/pressure monitor/control devices by Circor. These NeSSI Gen III transducers and control devices can replace classic pressure-indicating gauges, indicating/controlling variable-area flowmeters (rotameters), and pressure-controlling regulators.

An early adopter of this technology was a catalyst producer. In its R&D pilot plants in the Midwest, the company used classic proportion laboratory analyzers with NeSSI three-generation system technologies.

Another early adopter was the West Coast refinery of a major international refining company. In this refining application, analyzer maintenance personnel justified the NeSSI three-generation system concept based on reduced maintenance time requirements. Maintenance personnel would no longer walk long routes on a daily basis, tapping on pressure gauges and rotameter tubes to see if the reading was current, or if the indicator (needle or float) was stuck in some position within the instrument. Instead, this refiner’s personnel would enter their analyzer shop each morning and check an "exception printer." The NeSSI devices would communicate through the NeSSI-bus Gen II communication system onto the refinery fiberoptic communication network to generate an exception report for any analyzer where pressure or flow values were outside of preset limits. Now the maintenance personnel would only visit process analyzer applications where a problem was known to exist based on monitored and transmitted data. Maintenance personnel were now able to use their time to perform preventive maintenance activities to further reduce process analyzer field problems.

Today's process units in most CPI/HPI plants were built between 1944 and 1974. In the ensuing 50+ years, they have become incredibly complex and crowded as modifications, optimizations and upgrades have been "shoehorned" into the original plot plan. Today’s economic climate is one of "What have you done for me this quarter? Positive results this fiscal year?" Nobody but engineers want to wait two to three years for design and construction and another one or two to turn a profit from the resulting process unit performance. The HPI/CPI can no longer afford classic model process analyzer systems enclosed in classic model process analyzer shelters.

HPI/CPI operating companies must communicate to process analyzer companies, process analyzer system component companies and process analyzer system integration companies, and tell them that products using the "NeSSI concept" need to be developed within their organizations. This must take place in order for widespread application of NeSSI process analytical measurement system applications to be deployed.

The critical requirement for these near-future process analytical systems is to control input to the more easily understood and currently implemented industry-wide advanced process control initiative. HPI/CPI processes can’t be controlled without reliable knowledge of process variables reported within the timeframe of the response dynamics of HPI/CPI processes.

The reengineering of classic process analyzer system components to the NeSSI format typically results in equal-or-better performance from the NeSSI format device due to advances in machining and material technologies. If well-respected process analyzer and process analyzer component vendors produce well-engineered NeSSI systems, these vendors will be rewarded with significant sales opportunities in support of NeSSI systems and the NeSSI maintenance model. The hydrocarbon and chemical processing industries need cost-effective process analyzer systems. Which process analyzer vendor will fulfill this HPI/CPI requirement?