Thursday, April 19, 2018

Mountain States Engineering & Controls

Mountain States Engineering & Controls is a Manufacturer's Representative & Distributor of process equipment and controls headquartered in Lakewood, Colorado since 1978. We serve the markets of Colorado, New Mexico, Wyoming, Montana, Utah, Nevada, Idaho, and the western Dakotas.

https://mnteng.com
303-232-4100

Tuesday, March 27, 2018

Steam - Desuperheating and Attemperation

electric power generation plant
Steam is a motive force used to generate electric power
Industrial operations of many types utilize steam as a heat or power source, plus there is electric power generation. Steam is an important sort of "back office" component of the lives of many dwellers in modern economies.
What is steam?
Sorry, but we need to get everybody on the same page here. Steam is water vapor, produced by the application of heat to water. In order for steam to do work and serve as a useful energy source, it must be under pressure. There can be applications that employ steam at atmospheric pressure, but most are pressurized.

The heat goes on, the water boils, steam is produced and flows through the piping system to where it is used. Sounds simple, sounds easy. It is not. There are intricacies of designing and operating a steam system that determine its raw performance, as well as how efficiently it uses the fuel or other heat source employed to boil water. Steam utilization equipment is also carefully designed to provide its rated performance when supplied with steam of a given condition.

Steam at any given pressure has a saturation temperature, the temperature at which the vaporized water content of the steam is at its maximum level. Heat steam above its saturation temperature and you have superheated steam. Cool it below the saturation temperature and vapor will start to condense. The way in which the steam is to be used determines whether, and how much, superheat is desirable or necessary.
  • Turbine operations benefit from properly superheated steam because it avoids exposure of the turbine to liquid water droplets, generally a source of surface erosion and other accelerated wear.
  • Heat exchanger performance is based upon certain inlet conditions, one of which is the degree of superheat.
  • Maintaining sufficient superheat throughout a continuously operating steam system minimizes the need for, and size of, a condensate return system
Processes are designed to deliver a predictable output when provided with known inputs. In the case of steam, the temperature of the steam may be an input requiring control. This brings us to attemperation, which in the case of steam most often refers to lowering the temperature of a steam supply. Attemperation and desuperheating (reducing the degree of superheat) are accomplished in a similar fashion, but with differing objectives. Attemperation involves simply controlling the temperature of the steam, without any direct regard for the level of superheat. Desuperheating, as a control operation, is not directly related to the temperature of the steam, just the degree by which it exceeds the saturation temperature at the current condition. For attemperation, steam temperature measurement is all that is needed. For desuperheating, pressure and temperature measurements are needed. Decreasing the temperature of superheated steam will naturally reduce the amount of superheat.

Some process requirements may focus on temperature of the delivered steam, without regard to superheat level. Others will rely on a specified level of superheat. The application scenarios are vast, with equipment available to accomplish whatever is needed.

Either operation can be accomplished with a specialized heat exchanger or other device that extracts heat from the steam. Another option relies on the addition of atomized water to the flowing steam to manage temperature or superheat level. Share your steam system challenges with steam system experts, leveraging your own knowledge and experience with their product application expertise to develop an effective solution.

Monday, March 19, 2018

Modular Refrigerated Air Dryer For Industrial Compressed Air

exploded view of refrigerated compressed air dryer
Modular construction of this refrigerated compressed
air dryer combines backup capacity with demand based usage.
Image courtesy SPX Pneumatic Products
Compressed air is a common, and in some cases lifeblood, utility and source of power in industrial plants and operations. It is well established that limiting the moisture in compressed air is preferred. Modern operations increasingly demand drier compressed air supply containing fewer contaminants. Some of the potentially damaging effects of moisture in compressed air systems include:
  • In air operated instruments, corrosion, leading to incorrect readings and false responses by plant operators.
  • In pneumatic controls, clogging of orifices and malfunction of controls due to rust and scale can result in additional maintenance and repair, even process malfunction or shutdown.
  • Spray-on coating operations are impacted by moisture level, which can affect color, finish, and adherence of the applied material.
  • In industrial production equipment, moving parts can experience rust and premature wear due to the washing away of lubrication by excessive moisture in compressed air.
When ambient air is compressed, its temperature increases, but also does the ratio of water per unit of air volume. This results in a compressed air supply with what may be an unacceptably high dew point. Dew point is the temperature at which air is saturated, and cooling air below its dew point will result in the formation of condensate (liquid water). As compressed air is consumed by usage equipment, the air pressure drops, along with the temperature. These condition changes, and others, can result in condensate formation in the compressed air system and connected equipment. This is generally considered a negative development, as the presence of excessive moisture can lead to line freezing, corrosion, excessive equipment wear, and malfunction.

For many industrial applications, removing moisture from compressed air can be accomplished on a continuous basis utilizing a properly configured mechanically refrigerated air dryer. SPX Flow Techonology's Pneumatic Products brand of refrigerated air dryers applies best in class refrigeration technology to deliver substantial energy savings to the process. The ESM product line features:
  • Measurable energy savings.
  • Rapid return on investment
  • Load matching performance
  • Modular construction for multi-station design with isolation for service and maintenance
  • Fault tolerant operation
  • Integral filtration
More detail on the versatility, energy savings, and all around performance of the ESM Series Refrigerated Air Dryers is provided in the product data sheet included below. Product specialists can help you leverage your own knowledge and experience into a successful and effective solution.



Thursday, March 15, 2018

Regenerative Turbine Chemical Pumps

regenerative pump for chemical applications
Regenerative turbine pump for chemical applications
Image courtesy Roth Pump Company
A regenerative turbine pump is significantly different from a centrifugal pump in the way in which liquid moves through the impeller section, making the turbine pump a better performer in a number of industrial applications.

A centrifugal impeller basically traps some liquid at the inlet and rapidly slings through the discharge port. The liquid velocity is increased by the impeller and manifests as outlet pressure. A key distinction between centrifugal and regenerative turbine pumps is that the liquid enters and exits the impeller only one time in a centrifugal pump. A regenerative turbine pump has an impeller with a larger number of smaller, specially shaped vanes. The shape imparts a circulatory movement of the liquid from the vanes to the casing, and back to the vanes. Each return to the vane section increases fluid velocity, resulting in increased pressure. As the impeller rotates, liquid enters, leaves, then re-enters the vane section many times. This process is called regeneration. The impact of this design is a pump that can deliver substantially greater pressure than a centrifugal pump with the same impeller diameter and rotational speed.

A regenerative turbine pump is capable of pumping fluids with up to forty percent entrained gases without damage from cavitation or any performance loss. Fluid conditions with even low levels of entrained gases are generally not recommended for centrifugal pumps because of the degradation in performance, evidenced as fluctuating discharge pressure and excessive wear and vibration. Where cavitation is a concern, the regenerative turbine pump holds the advantage over centrifugal. Applications with low flow and high head requirements will also be better serviced by a regenerative turbine pump.

For chemical applications, assuring compatibility between the casing, turbine, and seal materials is an important step. Performance curves for the various pump models can be used to match a pump and motor combination to the application. Share your fluid transfer requirements and challenges with experts, and leverage your own knowledge and experience with their product application expertise to develop an effective solution.

Wednesday, March 7, 2018

Combining Rupture Discs With Pressure Relief Valves

pressure safety valve
A safety valve protects closed systems from excessive pressure
Image courtesy Kunkle Valve Division - Pentair
Safety and pressure relief valves are common elements of any pressurized system. Their general purpose is to provide a positive means of preventing system pressure from exceeding a preset value, avoiding uncontrolled events that could result in damage to personnel, environment, or assets. Their operating principle and construction are comparatively simple and well understood.

Long term exposure of a relief valve to certain types of process media can result in corrosion, material buildup, or other conditions which may shorten the useful life of the valve, or worse, impair its proper operation. This excessive wear will increase the ongoing cost of maintaining or replacing a prematurely worn valve. One other aspect of relief valves can be the reduction in their seal integrity or force as the system pressure approaches the setpoint. This could possibly lead to fugitive emissions, an undesirable condition.

An effective approach to mitigating some of the effects of exposure to the process media is to install a rupture disc upstream of the safety valve inlet. Isolating a relief or safety valve from the process media through the installation of a rupture disc upstream of the valve inlet eliminates exposure of the costly valve to effects of the media. It is necessary to establish proper rating and selection for the rupture disc to avoid any impairment of the overall operation of the relief valve, but the selection criteria are not complex. A number of benefits can accrue with this concept.

  • Rupture disc isolates the valve from the media, allowing application of less costly valves fabricated of non-exotic materials.
  • Rupture discs are leak free and bubble tight, eliminating possibility of fugitive emissions from the safety relief valve, especially when system pressure may approach valve setpoint.
  • Relief valve inventory can be evaluated for reduction.
  • Longer valve life.
  • Less downtime.

The additional cost for the rupture disc enhancement can have a reasonable payback period, with all factors considered. In any case, the rupture disc protection makes for a cleaner relief valve installation. Rupture discs and holders are available in sizes and materials for most applications. Share your ideas with a valve specialist, combining your process knowledge with their product application expertise to develop an effective solution.

Friday, February 23, 2018

Industrial Diaphragm Valves

sectional drawing weir type diaphragm valve with pneumatic actuator
Section drawing of diaphragm valve, weir type,
with pneumatic actuator.
Image courtesy Gemu Valves, Inc.
Diaphragm valves are named for the means employed in their design to restrict the path of fluid flow through the valve. Most valve designs employ a rigid solid shape which is repositioned in the fluid path to regulate flow. Diaphragm valves are somewhat unique in their use of a flexible material that is deformed by a moving part connected to the valve operating mechanism. The diaphragm acts as the flow restrictor and seat. It also isolates the valve bonnet and stem from the flowing media.

The fluid path and diaphragm positioning and seating enable this valve type to be used for throttling or simple stop operations. They are generally tolerant of particulate matter entrained in the media. Selecting body and diaphragm materials that are compatible with the media are primary elements of achieving a successful application. The diaphragm is a wearing part and should be inspected periodically and replaced when necessary.

Diaphragm valves for industrial use are available in a range of materials and sizes to accommodate light through heavy duty applications.
  • Suitable for inert and corrosive liquid and gaseous media when proper valve body and diaphragm materials are selected
  • Bonnet and valve bodies available in metal or plastic construction
  • Insensitive to particulate media
  • Valve body and diaphragm available in various materials and designs
  • Compact design
  • Automation via pneumatic or electric means
Share your fluid process control challenges with valve application specialists. Leverage your own knowledge and experience with their product application expertise to develop an effective solution.

Sunday, February 18, 2018

Getting Benefit From Waste Steam With a Thermocompressor

steam thermocompressor
Steam thermocompressor enables use of waste steam
in higher pressure applications.
Image courtesy Spirax Sarco
Steam, with its utilization as a means of transferring heat, as well as a motive force, is found in use throughout many industries. The production of steam is a significant cost of operation for any business where it is employed. Steam, after performing its intended function, still contains a comparatively large amount of heat, so methods of recovering or utilizing that heat energy remaining in waste steam is a positive step in conservation.

Energy conservation and energy efficiency have contributed very large cost savings to many industrial and commercial operations over the past two decades. Projects with modest payback periods quickly contribute to the bottom line of the operation's balance sheet. It is not uncommon for  energy conservation and efficiency measures contribute to improvement in the overall functioning of the steam utilization equipment or systems. In order to save energy, it is generally necessary to exercise better control over equipment or system operation by gathering more information about the current operating state. This additional information, gathered through measurement instrumentation, often finds use in several ways that improve productivity and performance.

A thermocompressor is a type of ejector that mixes high pressure steam with a lower pressure steam flow, creating a usable discharge steam source and conserving, through reuse, the remaining heat content of the otherwise wasted low pressure steam. The device is compact and simple, with no moving parts or special maintenance requirements. Two general varieties are available. A fixed nozzle style is intended for applications with minimal variation in the supply and condition of the suction steam (the low pressure steam). Some control is achievable through the regulation of the high pressure steam flow with an external control valve. A second style provides a means of regulating the cross sectional area through which the high pressure steam flows in the nozzle. This style is best applied when specific discharge flow or pressure is required, or there is significant variation in the inlet steam conditions.

Share your steam system challenges with a steam system application specialist. Leverage your own process and facilities knowledge and experience with their product application expertise to develop effective solutions.