Dust Measuring Instrument Combines Two Measuring Technologies

Model C200 combines transmittance and forward scattering
light methods to produce wide range dust measurements
Sick, Inc.

In the power industry, as well as others, dust and particle detection and measurement in emissions is an important element of compliance with environmental protection regulations. Stacks, ducts, and other conduits of gas or air transmission can be accurately monitored using instrumentation which incorporates the use of controlled light sources, sensitive detectors, and advanced processing software.

Two light based dust measurement methods of note are transmittance and forward scattering. Sick USA (pronounced like "seek"), in their extensive line of dust measurement instrumentation, offers a unit incorporating both of these technologies to provide accurate measurement across a wide range of conditions not attainable with units employing either of the technologies singly. The system consists of two compact enclosed units which are mounted on opposing sides of a duct or pipe. These house the light sources and detectors. There is also an enclosed control unit which is remotely mounted. A range of configuration options are available to meet specific application requirements and interface with a centralized control or monitoring system.

• Transmittance and scattered light measurement combined in a single instrument
• Suitable for dust concentrations from very low to high
• Self check of zero and reference point are automatic
• Contamination monitoring and compensation on both sides
• Automatic self-alignment
• Designed for medium to large duct diameters
• Suitable for sharply fluctuating dust concentrations
• Reliability achieved through redundant measurement
• Self-monitoring activity keeps maintenance requirements low
• Equipped for limit values that will become smaller in the future

The data sheet included below provides additional detail. More information about the complete line of dust measurement instrumentation is available. Share your emission monitoring requirements and challenges with application experts. The combination of your process knowledge and their product application expertise will bring effective solutions.

Dual technology dust measurement instrument from Classic Controls, Inc.

Process Gas Chromatograph - Practical Implementation of Parallel Chromatography

Process Gas Chromatograph
Yokogawa GC8000

Gas chromatography is a common analysis tool employed in many areas of the process control industry, including oil and gas, pharmaceutical, chemical, and others. Yokogawa Corporation of America developed instrumentation to provide top tier GC performance with their GC8000 Process Gas Chromatograph for use in oil and gas, and other industrial applications.

In addition to the ruggedness and reliability for which Yokogawa gas chromatographs are well known, the GC8000 brings a number of innovations and improvements to the company’s process gas chromatography product offering.

> Color touchscreen HMI for easy operation

> Advanced predictive diagnostics and software functions monitor key performance indicators during each analysis to verify analyzer is operating within proper tolerances.

> Parallel chromatography is made practical through the use of the GC Modules provided as part of the GC8000. Virtual GCs can be set up inside a single GC with GC Modules to measure multiple streams simultaneously.

The graphics below expand on this overview of the GC8000 Process Gas Chromatograph, the culmination of Yokogawa’s 55 years of experience in the field. For more detailed information, or to discuss your application specifics, contact a product specialist.

Process Gas Chromatograph for Industrial Use from Classic Controls, Inc.

Electric Actuators for Industrial Valve Automation

Multi-turn Electric Actuator
AUMA

Electric actuators bring automation to industrial valve operation, allowing complex processes to be managed and controlled by remotely located control systems. There are other motive forces used for valve actuators, including hydraulic and pneumatic, but electric actuators carry their own particular set of operating characteristics that make them an advantageous choice for many applications.

Valve actuators are available in uncountable variants to suit every application scenario. There are three basic valve actuation motions.

• Multi-turn, with repeated rotations of the valve shaft needed to move the valve trim from fully open to fully closed. A gate valve is a multi-turn valve. These are also called linear, with respect to the motion of the closure element. The term "linear", in this case, refers only to the movement of the valve trim and not the flow characteristics of the valve.
• Part Turn, where a 90 degree rotation of the valve shaft produces a change from opened to closed. Ball valves are in this category.
• Lever, generally associated with damper control.

An electric actuator is a combination of motor and gearbox with sufficient torque to change valve trim position. A local self-contained control commands the motor and provides feedback to the process master controller regarding position, travel, torque, and diagnostics. Several interface options are available to facilitate communication between actuator and master controller.

There are numerous considerations to take into account when selecting an electric actuator.

• Torque needed to effectively operate the subject valve.
• Actuator enclosure type - wash down, hazardous area, dust, etc.
• Service area for the assembly - corrosive environment, temperature extremes, and more
• Valve movement - linear, multi-turn, part turn, lever
• Operation mode - open and close only, positioning, modulating
• Frequency or duty cycle - infrequent, frequent, or almost continuous positioning
• Communication - How will the local controller communicate with the central control system?
• Electrical - What electric power characteristics are available for operation?
• Protections - Motor overload, torque limit, others
• Process Safety - Among other things, what happens if power fails? 

There are certainly other elements to consider when applying an electric actuator for industrial use. You can see more detail about electric actuator operation and available configurations in the document included below. It is well illustrated and clearly describes the various aspects mentioned in this article. Share your valve and actuator requirements and challenges with product specialists, combining your process knowledge with their product application expertise to forge the most effective solutions.

Electric Actuators for Industrial Valve Automation from Classic Controls, Inc.

Hydrostatic Level Measurement

Submersible Pressure Transmitter
VEGA

Liquid level can be inferred by accurately measuring the pressure produced by the height of a fluid column and knowing the density of the liquid measured. The measurement is comparative in nature, referencing some external pressure as a zero point. The zero point can be the surrounding atmospheric pressure, tank pressure, or the pressure exerted by another column of liquid contained elsewhere.

There are uncountable application scenarios, each with its own set of special conditions. Proper instrument selection, installation and calibration are essential to generating reliable and accurate results.

The VEGA hydrostatic pressure transmitters are specially designed to provide level measurements across a wide range of liquids with different properties. Some units provide media temperature measurement as well. The product centers around three basic units, with numerous variants and options that can be used to configure an instrument for any application.

Browse the document included below to see application examples, setup instructions, and the extensive array of configurations available with these pressure transmitters from VEGA. Contact product specialists to share your application challenges and get effective solutions.

Submersible Pressure Transmitter for Level Measurement from Classic Controls, Inc.

Steam Desuperheaters

Diagram of one type of steam desuperheater
Schutte & Koerting

Steam has been a preferred means of delivering energy for many decades. Whether used for propulsion, as when driving a turbine, or delivery of heat, steam has proven to be an acceptably reliable and safe means of energy transfer.

Steam can exist in a saturated or superheated state. When saturated, molecules are at the minimum energy level needed to maintain a gaseous state. Superheated steam is essentially steam that has additional sensible heat content beyond what is necessary to create saturated steam. Some processes, such as turbines, will operate best with superheated steam. Heat transfer processes will often provide their best efficiency with saturated steam. Whatever the case, there can be instances where it is preferential, or necessary, to reduce the superheat level of process steam.

Desuperheaters reduce the sensible heat content of steam through a number of methods, most that involve adding finely atomized water to the steam flow. The document included below outlines various construction methods and principles of operation for steam desuperheaters. The illustrations, diagrams, and explanatory content will provide a useful overview of this common industrial process, including application examples.

Types of Steam Desuperheaters from Classic Controls, Inc.

When to Use a Globe Valve for Fluid Process Control

Heavy duty industrial globe valve with pneumatic actuator
Masoneilan brand of GE

Industrial process control often involves the regulation of fluid flow. There are almost uncountable types and variants of flow control valves, each with a particular set of attributes that can make it the advantageous choice to meet certain applications.

When the process calls for controlling flow over a range of possible values, known as throttling, a globe valve may be a good candidate for the application.

Globe valves are characterized by the change in direction of fluid flow as it passes through the valve and the plug or disk positioned in an opening through which fluid must pass. The plug is connected to a stem extending to the exterior of the valve body through the bonnet. Movement of the stem will reposition the plug in relation to the opening, providing a successively larger or smaller opening area through which fluid can pass.

Simple globe valve diagram
Courtesy Wikipedia

Globe valves are available in tee, angle, and wye configurations, as well as an enormous range of special configurations to suit specific applications.

What are some potential advantages of globe valves?

• Good throttling and shutoff capability
• Comparatively easy maintenance
• Comparatively short travel of plug from open to closed position
• Seats can usually be resurfaced when worn

What are some limiting factors for globe valves?

• Higher valve pressure drop than some other designs
• No straight through fluid path
• Comparatively higher actuator torque requirements to operate valve

When flow throttling capability is the overriding concern for an application, a globe valve could be a good candidate for consideration. Share your flow control challenges with product specialists. Combining your process knowledge with their product application expertise will produce effective solutions.

Fuel Air Ratio Controller for Combustion Efficiency

Combustion efficiency reaps substantial cost savings

Steam and hot water use is prevalent throughout industrial processes. Production of these two media is most commonly accomplished with a boiler, many of which are heated by combustion of fossil fuel. Fuel fired boilers of a certain size become the focus of regulatory requirements for emissions. All boilers consume what would be construed by their owners as large amounts of costly fuel. Because of their high pressure and temperature, and the presence of a controlled combustion within an occupied facility, safety is a paramount concern.

There, fortunately, is a single solution that can help to attain useful goals with the three concerns of safety, fuel cost, and regulatory compliance. Applying an efficiency controller to manage the fuel to air ratio of the combustion system will deliver benefits far in excess of the cost to incorporate the necessary devices. The three basic goals for the fuel air controller are:

• Maximize fuel efficiency
• Minimize regulated emissions
• Maintain safe operating condition

A good portion of all three goals can be accomplished through careful concerted control of combustion air supply and fuel supply. The fuel air ratio must be subject to continual adjustment in response to current air conditions (which can vary on a daily basis) and the level of O2 in the flue gas. Controlling the air fuel ratio supports the following goals:

• Preventing excess fuel vapors from entering the flue and creating an unsafe condition
• Providing the correct amount of air to effectively combust the fuel supplied to the burner
• Preventing excess air flow from reducing net heat transfer to the feedwater
• Maintaining regulated emissions within required limits
• Limiting fuel consumption to the minimum necessary to meet demand

Fireye® is a leading manufacturer of flame safeguard controls and burner management systems for commercial and industrial applications throughout the world. Their products, the first of which was developed in the 1930's, enhance the safety and efficiency of all fuel fired burners.

There are numerous capabilities built in to the company's PPC4000 series of fuel air ratio controllers. Some of the more notable include:

• Precise fuel air ratio attained using parallel control of servos to regulate fuel and air supplies.
• User selected burner profiles
• Alarm contacts
• PID operation
• An array of inputs and outputs to accommodate sensors and devices needed to monitor and control boiler operation
• Compatible with other products that provide additional flame and burner monitoring safety
• Multiple boiler sequencing and cold start thermal shock protection
• On board boiler efficiency calculation
• User interface, optional larger touchscreen interface

Glance through just the first two pages of the document below to get a full description of the capability of this compact and comprehensive controller. You can get more detailed information, or get a professional evaluation of your current system efficiency, by contacting the combustion experts at Classic Controls.

Fuel Air Ratio Controller for Combustion Equipment from Classic Controls, Inc.