Interface Detection in Differentiated Liquid Pipe Flow with Clamp-on Ultrasonic Meter

Interface detection in differentiated liquid pipe flow refers to identifying and monitoring the boundary between two immiscible fluids (liquids that do not mix) flowing through a pipe in process control applications. In industries such as oil and gas, petrochemicals, and wastewater treatment, it is common to have a line transporting two or more immiscible liquids, often referred to as a multiphase flow. Efficient and accurate interface detection is crucial for optimizing separation processes, minimizing product contamination, and preventing damage to equipment.

Ultrasonic sensors transmit high-frequency sound waves through the fluid and measure the time it takes for the waves to reflect the interface. By analyzing the received signals, the sensors can determine the position of the interface within the pipe.

In process control, interface detection is often combined with other control strategies, such as flow rate control or temperature control, to ensure the efficient and safe operation of the process. Accurate interface detection allows for better process optimization, reduces the risk of equipment damage due to improper fluid handling, and improves overall product quality.

The Siemens SITRANS FS230 clamp-on ultrasonic interface detector is an exceptional option for applications that necessitate the detection of differentiated liquid pipe flow. It achieves this by computing the sonic velocity and pressure while adjusting for temperature variations. This direct measurement approach for interface detection leads to significant savings in equipment utilization and slop oil treatment.

The FS230 interface detector can provide oil companies with highly accurate and dependable flow and interface information for a broad range of applications, such as:

• Detecting gasoline interfaces
• Identifying multi-product interfaces
• Determining product types
• Managing automatic batching control
• Detecting entrained water and gas presence in all products

Ives Equipment

610-768-1600

https://ivesequipment.com

The Siemens Milltronics MSI Belt Scale

The Siemens Milltronics MSI is a high accuracy, full frame,  heavy-duty single idler belt scale used for process and load-out control suitable for monitoring products as diverse as sand, flour, coal, or even sugar. The Siemens Milltronics MSI belt scale provides continuous in-line weighing on a variety of products in primary and secondary industries and is proven in a wide range of extremely tough applications in mines, quarries, pits, power generating stations, iron and steel foundries, food processing plants, and chemical production facilities.

The Siemens Milltronics MSI patented use of parallelogram-style load cells results in fast reaction to vertical forces, ensuring instant response to product loading. This enables it to provide outstanding accuracy and repeatability even with uneven loading and fast belt speeds.

For more information, contact Ives Equipment by calling (877) 768-1600 or visit https://ivesequipment.com.

Reducing Material Waste in Flexible Pet (Polyethylene Terephthalate) Production

Polyester is very popular because it is a light, soft, flexible, low-maintenance material that keeps you warm. Making it this way poses diverse challenges to PET producers.

A chemical plant specializing in producing PET was looking for a solution to reduce the waste resulting from product variance. The factory produces 25,000 tons of polyester annually, which is then provided to other manufacturers to produce a vast range of end products.

The SITRANS FC430
monitors the glycol flow.

This vast range requires different PET grades, which are achieved by slight variations in the synthesis procedures. In order to investigate possible options to upgrade their primary processing, understanding the complete process is vital. In the case of PET production, this process starts with mixing three key ingredients – PTA and IPA powder along with glycol liquid – in specific ratios to make a paste.

These source materials are stored in stainless steel bins with a volume of 2649 ft3. Rotary feeders move the mate- rial from these bins to a batching vessel along with glycol to make the polyester paste. The batching vessel is agitated to ensure that the mixture is always consistent. Monitoring tank levels, precisely controlling the dosing, the efficient use of raw materials and ensuring a consistent mix are the key parameters

SIWAREX WP251

when it comes to improving the primary processing. When Siemens designed a new system for the chemical plant from the bottom up, the Siemens S7-1200 PLC controller was the first product that was installed to set up a compact and flexible automation solution, which keeps track of the key parameters and the process efficiency.

Don’t get mixed up during mixing

Each raw material bin is mounted on Siwarex WL280 ring torsion load cells to achieve optimum weighing accuracy. These load cells are connected to two Siwarex WP251 weighing modules, which are specifically designed for batching applications. The advantages of this solution are that the WL280 load cells feature a C3 class rating for accuracy as well as an IP68 rating for protection against dust and direct high-pressure cleaning – ideal for handling powder materials such as PTA. In connection with the Siwarex WP251, a customer-specific application was engineered with a resolution of up to +/- 4 million parts.

SITRANS TS500

The glycol as the liquid component in this process is monitored by a Sitrans FC430 coriolis mass flowmeter providing a 4-20 mA output, which varies based on the flow rate of the material. This signal is fed into an analog S7-1200 input module. A Sipart PS2 positioner controls the valves to regulate the flow rate. In such flexible processes as this one, the operator individually sets the setpoint for total production. At the field level, this flexibility is achieved using Sinamics variable frequency drives, which independently adjust the flow rate of each material. To close the loop, the discharge rates from the raw material bins are monitored by the WP251. The output is then processed by the S7-1200 controller, sent through an analog module to control the Sipart PS2 positioner – which in turn allows more or less glycol to flow into the batching vessel. The downstream Sitrans FC430 flow meter additionally verifies the flow rate to ensure a high-quality mix.

How powder and liquid become PET

Pointek CLS200

The temperature of the paste is another crucial factor when it comes to producing high-quality PET. If the agitation causes too much heat, the whole mixture could be lost, causing unwanted waste. In this configuration, a TS500 controls the temperature to the optimum level. To further cut down on product loss, a Pointek CLS200 capacitance- based switch acts as a backup device to ensure that the material discharges completely, and does not build up or overflow. Its high frequency oscillation makes it insensitive to product buildup, therefore guaranteeing reliable level monitoring in the PET paste vessel. For integrated control and alarm management, the level switch is connected to the S7-1200 controller. With 13 sensors, 2 VFDs, 3 geared motors, 4 modules and 1 HMI installed and connected to the control system, the plant managers reap the benefits of a comprehensive portfolio from one supplier. The new equipment is reliable and efficient and – together with the DCS solution – offers excellent process and data control.

Less material waste and reduced downtimes

SIPART PS2

Where did this leave the chemical company? After the equipment had been running for 3 months, the first estimates were made as to whether the initial goals of reduced waste and increased efficiency had been met. The result: plant efficiency had increased by 27 % due to the reduced material waste and product loss. Further, the more reliable process measurements and diagnostics help the company to service their equipment on a preventive basis instead of a reactive one, resulting in reduced downtimes and in- creased reliability.

Simplified diagram showing the customer’s process.

So the next time, you put on your running gear, take a sip out of a plastic bottle or attach your safety belt, maybe you will remember the effort that goes into producing the PET that is needed to manufacture these types of products. By the way – they have another important characteristic in common as they can be completely recycled.

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You can download the PDF version of this application note from this page on the Ives Equipment web site.

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Ives Equipment
877-768-1600
https://ivesequipment.com

Calibration Services for Process Instrumentation

Measuring, positioning, recording, and controlling are important parameters in all industries processes. That’s why process instruments need to deliver the highest levels of precision and reliability.

Today calibration measuring devices is an important production and competitive activity due to steadily increasing demands on reliability, availability and performance.

Off-site Calibration Services

Siemens offers factory calibration services for Pressure, Temperature and Flowmeters from both our own and other manufacturers.

On-site Calibration Services

Siemens offers on-site calibrations for Pressure, Temperature and Belt scale of our own products as well as those of other manufacturers.

This video presents the viewer with explanations and concepts for the following:

• The Siemens Process Instrument Services overview.
• A description of field instrument technologies.
• What calibration means.
• Reasons for calibrating field devices.
• The importance of calibration and verification.
• What traceability means.
• Why accreditation is needed.
• The Siemens Factory Calibration process.
• The Siemens On-site Calibration process.
• What verification means.
• Reasons for verification.
• The Siemens On-site Verification process.

For more information, contact Ives Equipment:
(877) 768-1600
https://ivesequipment.com

US Navy Supplier of MIL-SPEC Valves, Instrumentation, and Analyzers

Ives Equipment is an authorized US Navy supplier for ASCO, Worcester Valve, Niagara Meter (Venture Measurement), Siemens, and REOTEMP , registered under Cage Codes 1H855 and 6F024.

https://ivesequipment.com/navy
(877) 768-1600

Understanding Valve Positioners

Valve positioner on
linear control valve
(Siemens SIPART)

Industrial valves allow the flow of a process fluid through a pipe. Valves always include some type of actuation (opening/closing) device - from simple manual levers to sophisticated electric or pneumatic actuation packages. Industrial valves can act as on/off or proportioning devices to allow full flow, no flow, or modulated flow. When valves are used for modulating fluid flow, an instrument called a valve positioner is installed.

A valve positioner is used in tandem with a valve actuator, the power source to open or close the valve. Positioners precisely direct the actuator to move the valve so that a desired flow volume is achieved and maintained. The positioner does this by monitoring the process condition, comparing it to a desired set point, and then pneumatically, electrically, or hydraulically manipulating the valve orifice until the difference between the set point and actual process variable is zero.

In closed loop control systems where the final control element are valves, valve positioners are the "brains" that provide the corrective signal to eliminate process offset. Positioners enable tighter control by overcoming the realities of valve wear, imprecise calibration, and a host of other process variable challenges.

Valve positioners are used throughout the process industries including power, pharmaceutical, chemicals, oil and gas, food and beverage, pulp and paper, refining and petrochemicals, pipelines, and many other processes.

Basic Function

Diagram of typical flow control loop using valve positioner.

A valve positioner receives a signal from a controller. The controller could be part of a distributed control system (DCS), a programmable logic controller (PLC), or a discreet PID controller. The controller interprets a signal from some type of sensor, such as a flow transmitter, temperature transmitter, pressure transmitter, or other, and compares the transmitter reading to a desired setpoint. If the controller sees an offset (error), a corrective signal based on the difference, is sent to the valve positioner. The positioner then repositions the valve actuator that in turn readjusts the position of the valve, thereby changing the process condition, brining the system to to equilibrium.

Types of valve positioners:

Pneumatic Positioners

Pneumatic positioners receive pneumatic signals (3-15 or 6-30 PSIG) and proportion the supply air pressure to the valve actuator accordingly to move the valve to the required position. Pneumatic positioners are intrinsically safe and have the ability to provide a large amount of force to open or close a valve.

Electro-Pneumatic Positioners

Electro-pneumatic valve positioners are very similar to pneumatic postioners, except that they contain internal current-to-pneumatic converter (I/P). The current-to-pneumatic module receives a varying electrical signal (most commonly 4-20 mA) and converts that signal (proportionately) to a pneumatic output signal (3-15 PSIG or 6-30 PSIG). The pneumatic signal then then proportions the supply air pressure to the valve actuator.

Electric Positioners

Electric valve positioners receive an electric signal, usually 4-20 mA, 1-5 VDC, 2-10 VCD or 0-10 VDC and generally drive the motors in electric actuators. They perform the same function as pneumatic positioners do, but use electricity instead of air pressure as an input signal.

For more information on valve positioners, or any valve automation requirement, contact Ives Equipment by visiting https://ivesequipment.com or calling 877-768-1600.

Tutorial: How to Use the Push Buttons on the SIEMENS SITRANS P Family of Transmitters

The SIEMENS SITRANS P stands above the competition when it comes to easy operation. This video provides an outstanding tutorial on how the SITRANS P push buttons and display are used.

SITRANS P offer a complete family of devices that include digital pressure transmitters for measuring gauge pressure, absolute pressure, differential pressure, flow and level.

https://ivesequipment.com
(877) 768-1600

Accurate Low-Flow Measurement and High-speed Communication in Supercritical Fluid Extraction and Chromatography Systems

Low-Flow Measurement in Supercritical Fluid Extraction

A food producer removes caffeine from coffee beans to create a decaffeinated version of its most popular blend. A manufacturer of dietary supplements extracts pesticides and organic solvents from ginseng to ensure a higher-quality end product. A crime laboratory measures the amount of morphine in a blood sample to analyze the usage habits of a drug addict.

These scenarios might not appear to share much in common – after all, what does your favorite morning beverage have to do with forensic drug testing? – but there are important similarities. In each example, a supercritical fluid can be used to carry out precise, efficient, low-toxicity chemical extraction or chromatography.

SITRANS F C MASS 2100
sensor paired with the
SITRANS FCT010
digital transmitter

Regardless of the industry or application, supercritical fluid extraction (SFE) and super- critical fluid chromatography (SFC) require a very specific set of operating conditions. Keeping the environment just right for SFE and SFC requires consistently accurate process measurements – all of which are made possible by incorporating a high-performance Coriolis mass flowmeter designed to measure accurately at low flow rates.

Download this Application Note Here

The Application

An analytical science corporation in the northeastern USA develops instruments for laboratory-based applications across a broad range of industrial, academic and government organizations. Among their specialties are SFE and SFC systems tailored to the specific needs of customers and designed to extract and/or measure a variety of chemical compounds.

Their systems rely on supercritical carbon dioxide (CO2) instead of organic solvents to provide selective sample extractions and/or measurement. CO2 normally behaves as a gas at standard temperature and pressure, or as dry ice when frozen. But when CO2 is held at or above its critical temperature of 31.2 °C (87.8 °F) and critical pressure of 73.8 bar (1071.6 psi), it achieves a super- critical state midway between a gas and a liquid, with liquid-like density and solvating power but a viscosity near zero. Using supercritical CO2 results in shorter completion times and purer extracts – not to mention lower operating costs in comparison to solvent-based systems.

To kick off SFE or SFC, supercritical CO2 is pumped into the system and passes through an integrated Coriolis flowmeter, which measures the incoming mass flow rate, density and temperature. This is a crucial step in both processes, as it’s the prima- ry way to ensure that all CO2 flowing into the system remains in the desired fluid state. Once conditions are verified by the flowmeter, the CO2 helps to extract the compounds (in SFE) or separate and measure them (in SFC).

The Challenge

For more than 15 years, the company has had the option to add a SITRANS F C Coriolis flowmeter from Siemens to their SFE and SFC systems, depending on customer requirements. Their meter of choice consisted of a MASS 2100 sensor in size DI 1.5 (1/16”) and a MASS 6000 transmitter. They initially selected the Siemens solution because of its capability for very accurate measurement – as high as 0.1% of flow rate – under the low-flow conditions required for chemical extraction and measurement with supercritical CO2. The robust construction of the MASS 2100 sensor also offered the reassurance of long-term durability, even in high-pressure environments.

Over time, the company recognized the need to expand into a broader market- place by ensuring that all of their super- critical fluid solutions complied with the RoHS Directive for hazardous materials, which would open the opportunity to sell into the European Union. Having come to appreciate the reliability of the SITRANS F C product line and the responsiveness of Siemens customer support, they turned to Siemens for a digitally based, RoHS-compliant Coriolis flow alternative. That’s when they were introduced to the SITRANS FCT010.

The Solution

Part of the next-generation digital flow platform from Siemens, the FCT010 is a powerful, very compact Coriolis transmitter designed especially for skids and other small-footprint assemblies – a major benefit for the SFE and SFC systems given their limited availability of space.

Another prerequisite for selection was superior performance, and the FCT010 does not disappoint. The transmitter measures with advanced digital signal processing technology, so it produces a stronger signal-to-noise ratio than an analog transmitter for higher accuracy, improved resistance to process noise and a more stable zero point. The FCT010 can also detect and respond to even the smallest changes in flow with a best-in-class 100 Hz update rate.

The company was pleased to learn that the new transmitter could be paired seamlessly with the existing MASS 2100 sensor, which over the course of 15 years has proven to be the ideal low-flow sensor for measuring supercritical CO2. They also liked that the FCT010 is extremely simple to install as a result of its small size and easy-to-use wiring connections.

Ultimately, they placed an order for 100 FCT010 transmitters to be included with new SFE and SFC systems. Now that the enhanced Coriolis flow solutions are in place, the upgraded systems are benefit- ting from faster communication coupled with better process data – all of which adds up to higher-precision, more effi- cient extractions and measurements for laboratories.

With help from the digitally powered SITRANS F C Coriolis flow family, the corporation is equipping manufacturers and researchers with advanced tools that optimize science, commerce and their bottom lines.

For more information, call Ives Equipment at (877) 768-1600 or visit https://ivesequipment.com.

Reprinted with permission from Siemens.

An Exceptional Clamp- on Ultrasonic Flow Measurement Solution for Any Liquid Process

The SITRANS FS230 digital clamp-on ultrasonic flowmeter is a process-optimizing solution for measuring flow in virtually any liquid application. Designed to provide both exceptional performance and outstanding cost savings, the FS230 is an ideal fit for many industries requiring high-quality liquid flow measurement – including water and wastewater, HVAC and power, food and beverage, pharmaceutical, chemical, mining and pulp and paper.

The SITRANS FS230 flow system consists of a SITRANS FST030 transmitter paired with SITRANS FSS200 clamp-on ultrasonic sensors, which are available in three different models: WideBeam® (High-Precision), Universal and High-Temperature.

Download the PDF from the Ives Equipment web site here, or read the document embedded below.

For more information, contact Ives by calling 877-768-1600 or by visiting https://ivesequipment.com.

SITRANS FS230 Ultrasonic Flow Measurement from Ives Equipment

SIEMENS SITRANS LR250

The SIEMENS SITRANS LR250 is a great choice for liquid level measurement in storage and process vessels up to 66 feet (20 meters). With a variety of antennas, the LR250 can handle a broad scope of level applications. The SITRANS LR250 flanged and hygienic encapsulated antennas mean corrosive or aggressive materials and hygienic or sanitary requirements are no challenge for this transmitter.

https://ivesequipment.com
877-768-1600

Siemens SIWAREX WT231 and WT241 Weighing Terminals

The SIWAREX WT231 and WT241  are weighing terminals for industrial use. Siemens standard components are installed in a stainless steel enclosure with numerous connection options. This ensures the tried and tested SIWAREX quality as standalone solution and is ideal for container weighers or platform scales.

SIWAREX is the optimum solution wherever strain gauge sensors, such as load cells, force sensors or torque measuring shafts, are used for measuring tasks. The typical applications of SIWAREX  are:

• Non-automatic scales
• Fill level monitoring of silos and bunkers
• Measuring of crane and cable loads
• Load measuring for industrial lifts and rolling mills
• Force measuring, container weighers, platform scales and crane scales

SIWAREX offers the following key advantages:

• Complete solution – no configuration in SIMATIC required
• Fast and easy commissioning due to intuitive operating concept
• The stainless steel enclosure permits applications in many diverse environments
• Integrated connecting terminals for up to 4 load cells
• Flexible connection to different systems through diverse interfaces
  • - four digital inputs
  • - four digital outputs
  • - one analog output
  • - RS 485 interface and Modbus RTU
• High resolution of the load cell signal of up to ± 4 million parts
• Comprehensive diagnostics functions
• Recovery-point for the simple restoration of all parameters
• Automatic calibration is possible without the need for calibration weights
• All diagnostic and error messages as well as all scale parameters in plain text
• 100-240 VAC supply range

Download the SIWAREX WT231 and WT241 brochure by clicking this link.

Contact Ives Equipment by calling 877-768-1600 of by visiting https://ivesequipment.com.

What Are Industrial Control Systems?

Control system diagram (click for larger view).

Control systems are computer-based systems that are used by many infrastructures and industries to monitor and control sensitive processes and physical functions. Typically, control systems collect sensor measurements and operational data from the field, process and display this information, and relay control commands to local or remote equipment. In the electric power industry they can manage and control the transmission and delivery of electric power, for example, by opening and closing circuit breakers and setting thresholds for preventive shutdowns. Employing integrated control systems, the oil and gas industry can control the refining operations on a plant site as well as remotely monitor the pressure and flow of gas pipelines and control the flow and pathways of gas transmission. In water utilities, they can remotely monitor well levels and control the wells’ pumps; monitor flows, tank levels, or pressure in storage tanks; monitor water quality characteristics, such as pH, turbidity, and chlorine residual; and control the addition of chemicals. Control system functions vary from simple to complex; they can be used to simply monitor processes—for example, the environmental conditions in a small office building—or manage most activities in a municipal water system or even a nuclear power plant.

In certain industries such as chemical and power generation, safety systems are typically implemented to mitigate a disastrous event if control and other systems fail. In addition, to guard against both physical attack and system failure, organizations may establish back-up control centers that include uninterruptible power supplies and backup generators.

There are two primary types of control systems. Distributed Control Systems (DCS) typically are used within a single processing or generating plant or over a small geographic area. Supervisory Control and Data Acquisition (SCADA) systems typically are used for large, geographically dispersed distribution operations. A utility company may use a DCS to generate power and a SCADA system to distribute it.

A control system typically consists of a “master” or central supervisory control and monitoring station consisting of one or more human-machine interfaces where an operator can view status information about the remote sites and issue commands directly to the system. Typically, this station is located at a main site along with application servers and an engineering workstation that is used to configure and troubleshoot the other control system components. The supervisory control and monitoring station is typically connected to local controller stations through a hard- wired network or to remote controller stations through a communications network—which could be the Internet, a public switched telephone network, or a cable or wireless (e.g. radio, microwave, or Wi-Fi) network. Each controller station has a Remote Terminal Unit (RTU), a Programmable Logic Controller (PLC), DCS controller, or other controller that communicates with the supervisory control and monitoring station. The controller stations also include sensors and control equipment that connect directly with the working components of the infrastructure—for example, pipelines, water towers, and power lines. The sensor takes readings from the infrastructure equipment—such as water or pressure levels, electrical voltage or current—and sends a message to the controller. The controller may be programmed to determine a course of action and send a message to the control equipment instructing it what to do—for example, to turn off a valve or dispense a chemical. If the controller is not programmed to determine a course of action, the controller communicates with the supervisory control and monitoring station before sending a command back to the control equipment. The control system also can be programmed to issue alarms back to the operator when certain conditions are detected. Handheld devices, such as personal digital assistants, can be used to locally monitor controller stations. Experts report that technologies in controller stations are becoming more intelligent and automated and communicate with the supervisory central monitoring and control station less frequently, requiring less human intervention.

Contact Ives Equipment with any control systems question of challenge. Reach them by calling (877) 768-1600 or by visiting https://ivesequipment.com.

Increasing Safety in Chemical Waste Water Treatment Plant

Waste water treatment and location of the measurement.

Purified Terephthalic Acid (PTA) is the preferred raw material for the most common plastic products of daily life. The PTA production process generates various waste water streams which are high in organic content.

Purification of Process Waste Water

In the waste water treatment plant, the water treatment starts with aeration. The last step is an anaerobic bio reactor where the treatment is done in a controlled atmosphere. Micro organisms purify the water and produce biogas. Biogas roughly consists of 60 % methane and 40 % Carbon dioxide. This biogas is compressed and used as a fuel to reduce the net energy supply.

Although production or intrusion of oxygen into the reactors or pipes is highly unlikely, safety systems are installed. In case air enters unexpectedly into the process this first may result in a non-supporting atmosphere for the microbes and in the worst case the gas mixture may lead to an explosion.

Safety Guaranteed Using Siemens LDS 6

To ensure that oxygen never exceeds the maximum accepted concentration, the customer chose an in-situ measurement with the Siemens Laser Diode Spectrometer LDS 6. LDS 6 performs a continuous monitoring of the oxygen concentration in the biogas produced.

Measurement path and the
two LDS 6 sensor heads.

The response of the system is in three levels:

1. In case the oxygen level exceeds 5 % an alarm is triggered.
2. The threshold of 7 % causes an automatic nitrogen injection and the closure of a valve preventing the gas mixture from entering into the compressor.
3. When the limit of 9 % is exceeded, this automatically shuts down the compressor.

The in-situ measurement leads to a fast and reliable measurement.

The stability and availability of the LDS 6 system is ensured by the integrated reference cell which provides a lifetime calibration. To be absolutely on the safe side, the customer operates a weekly safety check which involves opening a valve that allows a controlled air intake into the LDS 6 sensor heads. As the sensor heads are physically separated from the process by process windows, no oxygen may enter into the process. The reaction of the system shows in any of these tests once more the reliability of the measurement method used.

For more information about this application, or for any analytical instrument requirement, contact Ives Equipment by calling (877) 768-1600 or visiting https://www.ivesequipment.com.

Reprinted with permission from Siemens Case Study.

Siemens Ultrasonic Level - How it Works

Ultrasonic level measurement is a highly cost-effective solution for short- and long-range measurement, even under difficult environmental conditions such as vibrations and dust. Ultrasonic level measurement is a non-contacting technology used in numerous industrial areas to monitor and control the level of liquids, slurries and solids.

Watch the video below for a better understanding of how this technology works.

For more information on Siemens ultrasonic level measurement, contact Ives Equipment by calling (877) 768-1600 or visiting http://www.ivesequipment.com.

Use of Process Analyzers in Fossil Fuel Plants

Steam Power Plant

In spite of all efforts concerning energy savings and efficiency, the growing world population and the aspired higher 'standard of living' will lead to a further in- crease of world energy demand. In this context, almost half of the primary energy demand will continue to be covered by solid fuels, particularly by coal, until 2020 and many years beyond.

This results in the challenge to power plant engineering to implement this increasing energy demand by using new technologies and applying the highest possible conservation of the limited resources of raw materials and the environment.

This includes new materials for higher operating temperatures and, therefore, higher efficien- cies of the power plants, as well as combined power plants that drastically reduce the share of unused waste heat or improved methods for reducing emissions.

Optimizing processes without delay, designing flexible operating conditions, improved use of the load factor of new materials and safely controlling emissions of toxic substances are all tasks that require the use of powerful measurement techniques. For this purpose, devices and systems of process analytics per- form indispensable services at many locations in a power plant.

In spite of all the alternatives, the undiminished increasing world energy demand also makes the expansion of energy recovery from fossil fuels necessary. However, the use of new materials and technologies further increases the efficiency of power plants and further reduces environmental pollution from the emission of toxic substances.

In this context, process analytics plays an important role: It determines reliable and exact data from the processes and thereby allows for their optimization.

Take a moment to review the document below, or if you prefer,  download the "Use of Process Analyzers in Fossil Fuel Plants" PDF file here.

Use of Process Analyzers in Fossil Fuel Plants from Ives Equipment

Differential Pressure Transmitters and Inferential Measurement

Differential Pressure Transmitter
(Siemens)

Differential pressure transmitters are utilized in the process control industry to represent the difference between two pressure measurements. One of the ways in which differential pressure (DP) transmitters accomplish this goal of evaluating and communicating differential pressure is by a process called inferential measurement. Inferential measurement calculates the value of a particular process variable through measurement of other variables which may be easier to evaluate. Pressure itself is technically measured inferentially. Thanks to the fact numerous variables are relatable to pressure measurements, there are multiple ways for DP transmitters to be useful in processes not solely related to pressure and vacuum.

An example of inferential measurement via DP transmitter is the way in which the height of a vertical liquid column will be proportional to the pressure generated by gravitational force on the vertical column. The differential pressure transmitter measures the pressure exerted by the contained liquid. That pressure is related to the height of the liquid in the vessel and can be used to calculate the liquid depth, mass, and volume. The gravitational constant allows the pressure transmitter to serve as a liquid level sensor for liquids with a known density. A true differential pressure transmitter also enables liquid level calculations in vessels that may be pressurized.

Gas and liquid flow are two common elements maintained and measured in process control. Fluid flow rate through a pipe can be measured with a differential pressure transmitter and the inclusion of a restricting device that creates a change in fluid static pressure. In this case, the pressure in the pipe is directly related to the flow rate when fluid density is constant. A carefully machined metal plate called an orifice plate serves as the restricting device in the pipe. The fluid in the pipe flows through the opening in the orifice plate and experiences an increase in velocity and decrease in pressure. The two input ports of the DP transmitter measure static pressure upstream and downstream of the orifice plate. The change in pressure across the orifice plate, combined with other fluid characteristics, can be used to calculate the flow rate.

Process environments use pressure measurement to inferentially determine level, volume, mass, and flow rate. Using one measurable element as a surrogate for another is a useful application, so long as the relationship between the measured property (differential pressure) and the inferred measurement (flow rate, liquid level) is not disrupted by changes in process conditions or by unmeasured disturbances. Industries with suitably stable processes - food and beverage, chemical, water treatment - are able to apply inferential measurement related to pressure and a variable such as flow rate with no detectable impact on the ability to measure important process variables.

Level Instrumentation for Your Entire Industrial Plant

Siemens level controls.

Whether you are measuring liquids, slurries or bulk solids, Siemens provides the ideal level measuring instruments for every job. Siemens level measurement devices set the standard in their respective disciplines for water, cement, mining, chemical, petrochemicals, food, beverage, pharmaceutical and other industries.

Point Level

Siemens level switches for point level measurement are distinguished by their outstanding performance. Their robust design ensures reduced cost of maintenance, spare parts, and downtime. Siemens level measurement instruments offer easy commissioning, connection to alarm or control systems, long service life, and low operating costs. Technologies include capacitance, rotary paddle, ultrasonic and vibrating.

Continuous

The product portfolio for continuous level measurement covers both contacting and non-contacting measurement. Radar, ultrasonic and gravimetric technologies are available for the non-contacting applications. Capacitance, guided wave radar and hydrostatic technologies are available for the contacting applications. As well, don’t forget that the safest engineered level measurement solution includes switches for back-up, overfill, low level and dry run protection. Technologies include radar, guided wave radar, ultrasonic, gravimetric, capacitance, and hydrostatic.

Interface

Siemens broad portfolio includes a large number of devices for many interface measurement applications, and includes the following products. SITRANS LC500, Pointek CLS 100, CLS 200, CLS 300 and CLS 500 are capacitance instruments for a wide range of tasks. The SITRANS LG uses guided wave radar technology.

Watch the entertaining video below to get a better idea of what level solutions Siemens (and Ives) has to offer.

Principles of Ultrasonic Flow in Industrial Clamp On Flow Meters

The video below demonstrate the principles applied to industrial clamp on flow meters using the SITRANS FS as an example.

The ultrasonic technology of the SITRANS clamp on flow meter provides highly accurate measurement of liquids and gases. With no pressure drop or energy loss, a wide turn-down ratio and no need to cut the pipe or stop the flow, installation is easy and maintenance is minimal.

For more information about ultrasonic flow meters, contact Ives Equipment at 877-768-1600 or visit http://www.ivesequipment.com.

An Industrial Valve Positioner that Offers Decisive Advantages

The SIPART ® PS2 electro-pneumatic valve positioner is used to control the final control element of pneumatic linear or part-turn valve actuators. The electro-pneumatic valve positioner moves the actuator to a valve position corresponding to the setpoint. Additional function inputs can be used to block the valve or to set a safety position. A binary input is present as standard in the basic device for this purpose.

The SIPART PS2 smart valve positioner is characterized by significant advantages compared to conventional devices, such as:

• Only one device version for linear and part-turn valve actuators
• Simple operation and programming using three keys and a two-line LCD
• Automatic startup function with self-adjustment of zero and span
• Manual operation without additional equipment
• Selectable or freely-programmable characteristics
• Minimum air consumption
• Selectable setpoint and manipulated variable limiting
• Programmable "tight shut-off function"

For more information about the Siemens SIPART 2 positioner download the detailed product brochure from this link,  or visit http://www.ivesequipment.com.

Vibrating Point Level Switch Operating Principles and Use

Vibrating point level switches (SIEMENS)

When asked the primary reason to remember the year 1711, the event probably not on the minds of many is the invention of a device called the tuning fork. The tuning fork has been used as an source of resonating pitch for over three hundred years, and is still used to tune musical instruments today. While the tuning fork was initially applied to tune musical instruments, the concept of resonant frequency of a material or object has been utilized in numerous commercial, scientific, and industrial applications to provide feedback or insight into a process or operation. The vibrating fork level switch is one such industrial application where resonant frequency is used to deliver a data point or provide a control output for process operation.

The operating principle of the vibrating fork is based on the oscillating fork resonating at a known frequency in air when it is set in motion. Upon contacting a medium other than air, the resonant frequency is shifted, depending on the medium contacting or immersing the fork. Typically, fork-type level switches are installed on either the side or the top of a liquid process tank. An exciter keeps the fork oscillating, and a detector circuit monitors fork vibrating frequency, providing a change in the output signal when the frequency changes. Contact or immersion of the fork in liquid will change the fork vibrating frequency sufficiently to produce a change in output signal. Depending on the configuration of the level switch, it can function as a liquid level alarm, or provide a control output for a pump, valve, or other device. Sensor response, the change in fork vibration frequency, is a function of liquid density. Liquids with greater density will generally produce a larger frequency shift in the vibrating fork.

The wide use of vibrating level switches across various process industries is a testament to the reliability of the technology. The devices protect against overfill, indicate high and low points inside tanks, and are useful over a wide range of temperatures. A sturdy design, coupled with product variants that include a variety of sensor materials, selectable probe length, and specialized output features make vibrating fork switches applicable in many operations where level indication is needed. Chemical processing, mining, food and beverage, plastics, and other industries utilize the switches, thanks to their customizable designs and consistent performance. An advantage offered by vibrating fork level switches is a resistance to factors that sometimes confound other technologies employed for level indication. The devices will reliably function despite flow, bubbles, foam, vibration, and coating complexities related to the subject liquids. Additionally, vibrating fork switches are reliable in both high level and low level indication scenarios.

Highly viscous liquids are generally not good candidates for the application of a vibrating fork level switch. Some liquids present the potential for material accumulation between the forks, possibly resulting in poor performance. Both of these limitations are addressed by various design features incorporated by different manufacturers.

The SIEMENS SITRANS LVS200 is a vibrating point level switch for high or low levels of bulk solids. The standard LVS200 detects high, low or demand levels of dry bulk solids in bins, silos or hoppers. The liquid/solid interface version can also detect settled solids within liquids or solids within confined spaces such as feed pipes. It is designed to ignore liquids in order to detect the interface between a solid and a liquid. Additionally, the SITRANS LVS200 has an optional 4 to 20 mA output for monitoring buildup on the fork to determine when preventative maintenance should be performed in sticky applications.

For more information on any level sensing application, contact Ives Equipment by visiting http://www.ivesequipment.com of calling 877-768-1600.