LDX Solutions https://www.ldxsolutions.com Mon, 05 Oct 2020 15:27:41 +0000 en-US hourly 1 https://wordpress.org/?v=5.5.1 How Much Baghouse Do I Really Need for My Process? https://www.ldxsolutions.com/how-much-baghouse-do-i-really-need-for-my-process/ Thu, 05 Mar 2020 20:14:11 +0000 https://www.ldxsolutions.com/?p=7863 The dirty process gas coming from your facility can be captured and cleaned before it is sent out to the atmosphere by installing a baghouse nearby and routing the gas to it. A baghouse can be up to 99% efficient when properly sized to accommodate the dust loading and volume of the process gas...

The post How Much Baghouse Do I Really Need for My Process? appeared first on LDX Solutions.

]]>

How Much Baghouse Do I Really Need for My Process?

Introduction Into Baghouse Sizing Calculations

The dirty process gas coming from your facility can be captured and cleaned before it is sent out to the atmosphere by installing a baghouse nearby and routing the gas to it. A baghouse can be up to 99% efficient when properly sized to accommodate the dust loading and volume of the process gas. How do we know if the baghouse is properly sized? How do we know if the baghouse can handle the CFM coming in and be effective? To answer these questions, we must first understand terms like air-to-cloth ratio and can velocity, as well as know how they impact the system.

Sizing Considerations

Air-to-cloth (A/C) ratio is the total volume of air/gas that the filter can handle. It is the ratio of gas flow to total bag filtration area. The A/C is important because an air-to-cloth ratio that is too high can cause bag blinding, high pressure drops, low cleaning/collection efficiency, and premature bag deterioration. However, having too low of an air-to-cloth ratio, while it does not have a negative impact on the design of the unit, can impact the size and ultimately add unnecessary cost to the baghouse.

LDX Solutions baghouse Installation

Can velocity, on the other hand, is the velocity at which the gas travels upwards across the cross section of the baghouse. Having a low enough velocity is essential in preventing the dust from remaining in a fluidized state, avoiding capture for removal. If too high, the dust that is being pulsed from the bags during cleaning will not fall into the hopper, but instead will get re-entrained in the gas and be carried back to the bag surface. This results in high pressure drop and premature bag deterioration.

Having the can velocity and A/C ratios known based on industry standards and experience, the baghouse can be sized to provide the best filtration in the most cost-effective way. Let us say you are working in the cement industry and you have a baghouse installed that cleans the gas before sending it off to the stack. Using an A/C ratio of 3.28:1 and the total cloth area (calculated by multiplying the bag filtration area by the number of modules and bags within that module), you can calculate how much flow the baghouse was designed to handle.

Example:

A/C ratio = 3.28 ft/min
Number of modules: 8
Number of bags per module: 285

Filtration area per bag: 39.81 ft2
Total cloth area = ~ 90,767 ft2
Total CFM = ~ 297,716 ft3/min

Low flow can cause dust buildup in the ductwork leading to the baghouse, eventually choking off the flow to the system and limiting the cleaning of the air or causing the duct to eventually structurally collapse. High flow, on the other hand, can mean high velocity which leads to erosion of the ductwork or inefficient cleaning of the dirty gas.

Conclusion

Baghouse design is a delicate play between engineering and art. Knowing information like process conditions, dust properties, and footprint available can significantly help LDX Solutions to provide the right product for your needs.
For more information on a baghouse design that is right for your operation, contact us at LDXsolutions.com.

LDX Solutions experts have been helping customers with design, research, and development since 1984. Tell us about your project so we can help you find the solution that will work best for your operation.

The post How Much Baghouse Do I Really Need for My Process? appeared first on LDX Solutions.

]]>
What is a Fabric Filter? https://www.ldxsolutions.com/what-is-a-fabric-filter/ Fri, 17 Jan 2020 19:01:17 +0000 https://www.ldxsolutions.com/?p=7512 Fabric filter is the technical term for what is commonly known as a baghouse or dust collector. A fabric filter is an air pollution control device that removes particulate matter from a process gas stream before it is emitted into the atmosphere...

The post What is a Fabric Filter? appeared first on LDX Solutions.

]]>

What is a Fabric Filter?

destruction of VOCs and HAPs

Fabric filter is the technical term for what is commonly known as a baghouse or dust collector. A fabric filter is an air pollution control device that removes particulate matter from a process gas stream before it is emitted into the atmosphere.

Dust laden gases come in contact with filter bags inside a baghouse. Depending on the type of fabric filter, dust comes in contact with the filter bag and either collects on the inside or outside of the bag.

Types of Fabric Filters

There are many types of “dust collectors” and terms used for the dry technologies that collect particulate matter from a gas stream. These terms include: Pulse-Jet Dust Collector System (can be a fabric filter), Reverse Air Baghouse, Cyclone, Cartridge Collector, or Shaker Collectors. However, for this brief we will focus on fabric filters.

destruction of VOCs and HAPs

There are several types of fabric filters, but they all have a few items in common:

  • Dirty air plenum
  • Clean air plenum
  • Tubesheet (holds the bags in place)
  • Filter media or bags
  • Hopper, or opening, to collect the dust
  • Cleaning system

Extensive Research and Development

In 1947, Dustex (now known as LDX Solutions) started engineering and designing high efficiency cyclones in response to the food industry’s need for product collection. Since then, the design and engineering has evolved, and the market has a variety of collection equipment for a variety of application. Today, the Dustex® branded products include many types of our designed and engineered dust collectors and fabric filters.

Types of Fabric Filters

For “fabric filters” or baghouses the main difference in the designs is how the filter bags are cleaned.

Pulse-Jet Fabric Filter

With a pulse-jet fabric filter, the bags are supported by metal cages and they hang from a tubesheet located at the top of the fabric filter. The process is such that as the dirty air enters the fabric filter, the dust/particulate matter is collected on the outside of the bags as the air passes from the outside to the inside; building up a dust cake. The now clean air then exits the fabric filter. Pulsing or short bursts of compressed air cleans the bags of the dust buildup at regular intervals; intervals can be determined by system differential pressure or time. Cleaning can be online, meaning this occurs while the fabric filter is still in operation, or offline, meaning the compartment no longer has process air flowing through it during the cleaning cycle.

Reverse Air Baghouses

A reverse air baghouse cleans at a lower pressure than a pulse-jet baghouse. Instead of using compressed air, cleaning air is generated by a low pressure/high volume fan which blows reverse air into the clean air plenum to remove the dust. Reverse air baghouses are typically cleaned offline.

A reverse air fabric filter collects dust on the inside of the bags (as opposed to the outside of the filter bags as seen on pulse jet units). No cages are supporting the bags so as the dust cake cuts off the inflow of dirty air, it uses the reverse flow of clean air to remove the dust. The bags partially collapse and remove the dust.

In the past, the argument for reverse air baghouses in lieu of a pulse-jet baghouse was that the high pressure and compressed air led to higher operating costs with a pulse-jet fabric filter. However, if designed properly for your operation, this cost can be kept in check. Improperly sizing a fan for a reverse air baghouse can be just as costly from an operational expense.

Shaker Baghouses

The shaker baghouse bags usually hang from the top of the unit and attach to the tube sheet at the bottom. The cleaning process is mechanically shaking the bags. Generally, the dirty air enters the baghouse from the bottom and is pulled through the inside of the bags, where the dust is collected. The cleaning process is off-line, meaning that the system must be shut off for the shaker to remove the dust.

In Summary

Note: There is a science to designing a system that meets your operation’s process conditions. It is important that you carefully consider an experienced and successful supplier with a long history of operating installations. A properly sized fabric filter and properly prescribed filter media or bags, can provide you with a high efficiency filtration system and long bag life.

Today, fabric filter technology is often prescribed as part of a solution for a plant process that not only has particulate matter in its process but also includes NOx, SOx, Mercury or some other form of gas pollutant.

We are available to assist you in determining your operation’s needs, so contact us at LDXsolutions.com.

LDX Solutions experts have been helping customers with design, research, and development since 1984. Tell us about your project so we can help you find the solution that will work best for your operation.

The post What is a Fabric Filter? appeared first on LDX Solutions.

]]>
How Does a Baghouse Work? https://www.ldxsolutions.com/how-do-baghouses-work/ Fri, 17 Jan 2020 18:21:20 +0000 https://www.ldxsolutions.com/?p=7494 A fabric filter, commonly referred to as a baghouse, is a dust collection device that houses filter bags, also known as filter media, which removes particulate matter/dust from process gases...

The post How Does a Baghouse Work? appeared first on LDX Solutions.

]]>

How Does a Baghouse Work?

What is a Baghouse

A fabric filter, commonly referred to as a baghouse, is a dust collection device that houses filter bags, also known as filter media, which removes particulate matter/dust from process gases.

Baghouses are utilized in many industrial applications to capture particulate matter
that is produced by a facility before it is emitted into the environment.

How It Works

The dirty gas stream enters the baghouse either via an inlet air plenum or directly into the hopper. Upon entry, the larger particulate matter drops directly into the hopper below, due to a decrease in conveying velocity. As the gas flows upward into the bag mass, the finer particles attach to the outside of the filter bags, allowing only the clean air to pass through the filter media, into the clean air plenum, and then released into the environment.

How Baghouse Works?

Once a layer of dust cake is built on the outside of the filter bags, bag cleaning takes place to regenerate the permeability of the filter media. The dust cake being built actually adds to the filtration efficiency of the system but eventually, this can begin to work against the system and provide too much resistance to the flow. The buildup of the dust cake on the filter bag increases the differential pressure measured over the baghouse which then prompts the cleaning process.

How fabric filter works?

CFD Model of Side-Entry Inlet Configuration

Dustex® Floating Pan Top Door

The upper body of the fabric filter, known as the clean air plenum, serves as the outlet to carry the filtered air into the atmosphere. Part of the cleaning system – the blowpipes, are also housed in the clean air plenum. Air headers with solenoid valves sit on top of the clean air plenum. The tube sheet is located below the blow pipes and holds the filter bags in place.

clean air plenum
How Floating Pan Top Door works?

The cleaning system consists of double diaphragm valves connected to the blowpipes and mounted over the bags. When cleaning is needed, there is a release of air stored in the air header through the blow pipes. This pulse of air comes from the actuation of the double diaphragm valve. Pressurized air is released to the dirty bags one row at a time. This pulse of air breaks the dust cake on the filter bags, releasing the dust into the hopper thus restoring normal flow through the filter media. Cleaning can occur at regular intervals based on a timer or can be dependent upon baghouse differential pressure. As differential pressure reaches a high limit, cleaning is started and continues until the differential pressure is returned to a low limit. A thin dust cake remains on the bag for further, more efficient filtration. The clean air exits the baghouse via the clean air plenum.

For more information on what baghouse is right for your operation, contact us at LDXsolutions.com.

LDX Solutions experts have been helping customers with design, research, and development since 1984. Tell us about your project so we can help you find the solution that will work best for your operation.

The post How Does a Baghouse Work? appeared first on LDX Solutions.

]]>
How RTOs Work https://www.ldxsolutions.com/how-rtos-work/ Wed, 18 Dec 2019 17:07:39 +0000 https://www.ldxsolutions.com/?p=7165 Perhaps the most fundamental parameter to be measured in gas handling systems is the flow rate. Determining the best method for measuring flow rate can be difficult. For low-pressure, non-toxic gas streams the pilot-tube...

The post How RTOs Work appeared first on LDX Solutions.

]]>

RTOs are Too Expensive to Operate – Fact or Fiction?

We frequently hear that regenerative thermal oxidizers (RTOs) are very expensive to operate.  After all, they do consume natural gas and normally operate at 1500°F or higher.  This can add up to very large natural gas or propane annual operating costs.

But what are the realities?  To understand, let’s consider some typical cases.

How an RTO Works

Before we do that, let’s look at how an RTO works.  An RTO is a simple VOC incineration machine that utilizes a well-known regenerative process that stores and returns heat in ceramic heat exchange beds.  As shown on the simplified diagram below, the back-and-forth cycling of the gas stream allows most of the energy in the combustion zone to stay within the machine so that the net temperature increase from inlet to outlet is minimized.  With this, the energy consumption is also minimized even though the contaminated gas is treated at more than 1500°F to destroy the pollutants.

How an RTO Works

Of course, how much heat is retained and returned within the RTO is a very important factor.  A term that is used to characterize this effect is thermal efficiency or TE. The higher the value of TE, the more energy efficient a given RTO design is.  For most RTOs the operating value for TE ranges from 90% to 97%.  A good way to think about the meaning of TE is this:  TE is the ratio of the energy recovered to the energy added.  For example, in the diagram above, the TE is 94% and can be calculated by dividing the the energy recovered (1500°F to 150°F) by the energy added (70°F to 1500°F); i.e., 1350°F /1430°F = 0.94.

The missing factor in all of this is the energy added by the combustion of the volatile organic compounds (VOCs).  Virtually all VOCs yield heat when they are burned.  The same is true for carbon monoxide.  To understand how much the VOC and/or CO contribution can make to the operating cost of an RTO we will look at some examples.

First a base case.  No VOCs or CO.  Just ambient air.

Assuming 100,000 scfm (440,000 lb/h) of air at ambient temperature of 70°F and a TE of 95% for the RTO we calculate an air temperature increase of 71.5°F.  To calculate the amount of natural gas required to heat the air one can use a simple equation;

Q = mCpT

Where

Q = total heat required (BTU/h)

m = mass of air being treated (440,000 lb/h)

Cp = heat capacity of air (0.25 BTU/lb°F)

T = temperature increase (71.5 °F)

From this we calculate, Q = 7,865,000 BTU per hour.  In terms of natural gas required, this is 78.65 therm/h and at $0.40/therm (2019 approx. rates) the hourly cost is $31.46.  On a yearly basis this is $275,589, a very significant addition to a plant’s overhead.

Second Case.  Add VOCs.

Suppose the gas stream has 500 ppm of VOC measured as propane.  500 ppm is, in fact, a very dilute amount representing only 0.05% of the gas volume.  Yet, it still adds a significant heat boost to the RTO operation as it burns in the combustion chamber.  Assuming it has the same heat content as propane, 18,000 BTU per pound, the 500 ppm of VOC adds 6,326,424 BTU/h to the energy balance of the RTO and results in a reduction in the natural gas consumed to only 1,538,575 BTU/h (7,865,000 – 6,326,424).  The annual gas bill now is only $53,918, translating to a lower yearly operating cost difference of $221,671.

Further, if the VOC concentration is 600 ppm the natural gas consumption falls to nearly zero and the RTO is approaching self-sustaining operation.

While this analysis does not include the relatively minor additions of radiant heat loss and burner combustion air it clearly shows how just a small amount of VOC can dramatically reduce the fuel requirements and operating cost of an RTO system.  The chart below shows this in more detail.

Finally, there is even more good news on this subject.  A TE of 95% is good but a TE of >96% is quite possible with today’s modern RTOs.  The 1% difference between 95% and 96% may not sound like much but it means 20% less fuel required.  And, as illustrated above, 20% can make a significant improvement in operating expenses.

Note that there is the catalytic approach, another fuel saver, but we’ll leave that for another technical blog.

For more information, contact us at LDXsolutions.com.

The post How RTOs Work appeared first on LDX Solutions.

]]>
Wet Electrostatic Precipitator Material Selection https://www.ldxsolutions.com/wet-esp-material-selection/ Tue, 19 Nov 2019 19:47:54 +0000 https://www.ldxsolutions.com/?p=7113 The selection of materials of construction for Wet Electrostatic Precipitators (wet ESPs, or WESPs) is a challenging problem. With metals, over specifying the alloy can make the project non-economical, while selecting...

The post Wet Electrostatic Precipitator Material Selection appeared first on LDX Solutions.

]]>

Introduction

The selection of materials of construction for Wet Electrostatic Precipitators (wet ESPs, or WESPs) is a challenging problem. With metals, over specifying the alloy can make the project non-economical, while selecting an insufficient alloy may threaten the longevity of the equipment. To further complicate matters, vendors of wet ESPs cannot be expected to offer long-term warranties with respect to corrosion, but this is exactly what end users want – reasonable assurance that the installed equipment will hold up to the application environment.
 
Plastic materials can be a solution to this problem but are certainly not a perfect solution. Plastics are subject to damage due to excessive temperature. They are also subject to arc damage from high voltage sparking. Finally, even with plastic designs the high voltage electrodes must be metal, so the same challenge of alloy selection is present…
 
To read the rest of the article, please submit the form below.

The post Wet Electrostatic Precipitator Material Selection appeared first on LDX Solutions.

]]>
Steve Jaasund – LDX Solutions and the Future of Emissions Control Technology https://www.ldxsolutions.com/steve-jaasund-geoenergy-ldx-solutions/ Mon, 11 Nov 2019 18:58:26 +0000 https://www.ldxsolutions.com/?p=7059 One of the first air emission control companies to advertise in Panel World magazine was Geoenergy®, and one of its co-owners was Steve Jaasund, who today is Geoenergy Products Manager for...

The post Steve Jaasund – LDX Solutions and the Future of Emissions Control Technology appeared first on LDX Solutions.

]]>

Steve Jaasund – LDX Solutions and the Future of Emissions Control Technology

JAASUND’S LONG RUN WITH GEOENERGY (LDX SOLUTIONS) ISN’T OVER.

Is Geoenergy part of LDX SolutionsEDITOR’S NOTE: One of the first air emission control companies to advertise in Panel World magazine was Geoenergy®, and one of its co-owners was Steve Jaasund, who today is Geoenergy Products Manager for LDX Solutions. The life and times of Geoenergy and Jaasund have been well documented through the years in Panel World. Further development in recent years prompted the following question and answer exchange. Jaasund can be reached at sjaasund@ldxsolutions.com

Panel World: The dust seems to have settled on the transition into LDX Solutions. Interestingly, the Geoenergy name survives, even in your title as Geoenergy Products Manager. Given that at one point you were the co-owner of Geoenergy, can you reflect on what Geoenergy has meant to you personally and professionally?

Jaasund: That’s a big question and very relevant to me on both fronts. My impression is that the names Geoenergy and Steve Jaasund are inexorably linked and rightfully so. Briefly stated, all things Geoenergy have been the central focus of my professional career for roughly 35 years.

In 1984 I left the corporate world and went out on my own as a consultant. While consulting was challenging and fun, my real passion was in the world of air pollution control equipment and specifically wet ESPs. So when a consulting job with fledgling Geoenergy International Corporation came up, I had an ideal entre into the world of capital equipment supply. In those days Geo was a three-man operation with one E-Tube® wet ESP on their reference list. To be successful the company desperately needed a change of ownership with a more go-go attitude. In reaction, two of my old friends from the University of Washington and I struck a deal with the Geoenergy owners to buy the company with sweat equity. It was a good deal for both parties and ultimately very successful for me and my partners. Starting in 1988 we grew the company from that three-man operation to a real force in the industrial air pollution control market with a special emphasis on the world of panelboard. In fact, I think it’s safe to say that by the year 2000 Geoenergy was the leader in emission control in the North American panelboard industry and a very significant supplier of emission control systems in many other industries.

However, the situation changed dramatically in 2002 when the company lost an employment contract lawsuit brought by a former employee. That forced us to close the company and declare bankruptcy. That was a very dark time for me and my family, costing nearly everything I owned. All I could hold onto was my knowledge, experience and my association with the name Geoenergy.

Fortunately, that knowledge, experience and Geoenergy association appealed to A. H. Lundberg Associates here in the Seattle area, and late in 2002 Lundberg purchased the intellectual property rights of Geoenergy from the bankruptcy trustee and hired me and my former partner Gary Raemhild. With that, Geoenergy was resurrected from the grave and a fresh start began.

Now, 17 years later the name Geoenergy continues to be a force in the market for emission control technology with a continuing focus on panelboard and related wood bioenergy industries. While the closure of Geoenergy International Corporation was a traumatic event, I think that today the name Geoenergy and the products and markets that go along with it are even stronger than they ever were. And it has been my great fortune to be associated with it. As they say, Geoenergy has meant the world to me.

Panel World: LDX Solutions combines several air emission control companies. Can you review how the transformation evolved in recent years?

Jaasund: LDX is the new name for the combination of Lundberg and Dustex. Here’s how this happened:

In 2015 Dustex in Kennesaw, Georgia was acquired by a private equity firm. About a year later Lundberg was also acquired. At that point the two companies were merged under the umbrella company, Dustex Holdings. The intent of this acquisition was to develop a broad-based supplier of emission control products for the industrial market. Given the dry treatment technologies at Dustex such as fabric filters, circulating dry scrubbers and dry sorbent injection systems and the Geoenergy wet ESP and RTO technology at the Lundburg office the new combined firm covered most of the bases. Most recently, the owners decided to put the new name, LDX Solutions, on the entire operation to give a clear message to the market that the two companies are now, indeed, the same company. This is not just a name change. Despite our different heritages and geographical locations we work together as a team on any and all projects.

Panel World: What is LDX Solutions bringing to the panel industry that may have been lacking, especially in product technologies?

Jaasund: It’s simple. There is always the need for higher efficiency, lower opex and lower capex. The wet ESP, RTO and scrubbing technologies of 1990s, while acceptable in those days, are not acceptable in today’s world. My colleagues and I have seen great improvement in the emission control technologies over the past decades and there is more to come. As a company this drive for better performance and lower costs is very real to us and there is a lot of R&D going on to achieve these goals. Tangible examples of these include smaller, more energy efficient RTOs that perform at 97% thermal efficiency and >99% DRE and wet ESPs that routinely achieve less than 10mg/Nm3. Improvements such as these directly translate into lower cost and higher reliability for a wide variety of manufacturing operations.

Panel World: How much advancement does there continue to be in air emission control technologies and what is driving this continuous improvement?

Jaasund: Throughout my career, I have seen that the demand for a cleaner environment has no limit. As long as the possibility of further emission reduction exists the public will demand it. This demand is reflected in regulatory mandates and drives companies like LDX Solutions to strive for the better performing products that I just mentioned. This then begs the question, just how far can we go? In today’s world of <10 mg/Nm3 particulate requirements and 1 ppm HAP demands, one might think that we have reached a practical limit. Well, from my point of view, based on my experience, we’re not even close to that limit. For me, when the gas stream coming out of a wood dryer is cleaner than the US EPA ambient air quality standard, then, and only then, can you say that we have reached a practical limit.

Panel World: Where do we stand with regard to EPA and government-body regulations and standards of air quality that impact the panel industry? Are there issues still pending?

Jaasund: Certainly there are issues still pending. The driver, of course, is the Clean Air Act, its amendments and future amendments. As time rolls on I am sure that restrictions on emissions will tighten and formally unregulated emission sources will be regulated. While the political leanings of the party in the White House matter, in my opinion they only matter on the margins. As I said before, the demand for cleaner air is insatiable and industries like the panel industry need to plan on tighter and tighter regulations in the future. Fortunately companies like LDX Solutions are working hard on developing technological innovations to satisfy these coming demands.

Panel World: What do you feel are some of the keys to a panel plant implementing and maintaining an excellent air control program?

Jaasund: It starts with taking environmental compliance seriously. Gone are the days when operators might thumb their noses at the local air pollution agency guy. Regulatory compliance is a very serious business and should be treated that way from the worker on the shop floor all the way up to the CEO. Fortunately, today’s generation of young people think that way and are virtually all very serious about obeying the rules.

If there is a weakness in this regard, I think that there may be a lack of skilled engineers and technical people out in the plants to ensure that emission control systems perform as required. I am not saying that this is a universal problem, but that the panel industry along with other process industries could use more chemical, mechanical and electrical engineers to watch over and maintain their emission controls. As compliance demands grow and the control technologies become more sophisticated it is important that there are people at the helm who understand how these things works. Unfortunately, many plants simply do not have the technical talent to understand their emission control systems efficiently despite a willingness to play by the rules.

Sources

The post Steve Jaasund – LDX Solutions and the Future of Emissions Control Technology appeared first on LDX Solutions.

]]>
The Benefits and Advantages of Wet Electrostatic Precipitators https://www.ldxsolutions.com/wet-esp-benefits-advantages/ Thu, 24 Oct 2019 20:46:41 +0000 https://www.ldxsolutions.com/?p=6930 As environmental requirements continue to change, the demand for better gas cleaning technology grows. This trend has continued to push the development of a relatively old technology – the wet electrostatic...

The post The Benefits and Advantages of Wet Electrostatic Precipitators appeared first on LDX Solutions.

]]>

Introduction

As environmental requirements continue to change, the demand for better gas cleaning technology grows. This trend has continued to push the development of a relatively old technology – the wet electrostatic precipitator (wet ESP, or WESP).

The man who first developed the concept of the wet ESP was Dr. Frederick Cottrell. First used in 1910 at a smelter in California for the collection of sulfuric acid mist, the wet ESP led to the development of the dry ESP. Until 1970, the wet precipitation technology remained a mainstay for acid mist control, but nothing else. The dry ESP became the dominant version of precipitation technology. Dry ESPs were used on thousands of boilers and furnaces around the world. In 1970, the regulatory push mandated by the landmark Clean Air Act rejuvenated interest in wet ESPs. Since the Clean Air Act, numerous innovative improvements in wet ESPs have led to opportunities in applications never anticipated…

To read the rest of the article, please submit the form below.

The post The Benefits and Advantages of Wet Electrostatic Precipitators appeared first on LDX Solutions.

]]>
Regenerative Thermal Oxidizer (RTO) Basics and Applications https://www.ldxsolutions.com/rto-basics/ Thu, 24 Oct 2019 20:45:44 +0000 https://www.ldxsolutions.com/?p=6924 The question often arises: Why can’t one operation’s RTO operate for decades, while another cannot? Regenerative Thermal Oxidizers (RTOs) that control volatile organic compounds emitted by a wide variety of industrial...

The post Regenerative Thermal Oxidizer (RTO) Basics and Applications appeared first on LDX Solutions.

]]>

Regenerative Thermal Oxidizer (RTO) Basics and Applications

Introduction

The question often arises: Why can’t one operation’s RTO operate for decades, while another cannot?
 
Regenerative Thermal Oxidizers (RTOs) that control volatile organic compounds emitted by a wide variety of industrial processes are widely accepted. As a general rule, RTO technology has been very successful with most installations, operating trouble-free for extended periods. In some cases, however, operation has been troublesome, and a good proportion of these problem applications have been on biomass dryers. Biomass dryers include wood dryers, sewage sludge dryers, and dryers used in ethanol production. This paper addresses why some RTOs have problems and how to avoid these problems…
 
To read the rest of the article, please submit the form below.

The post Regenerative Thermal Oxidizer (RTO) Basics and Applications appeared first on LDX Solutions.

]]>
Wet Electrostatic Precipitator Flow Direction https://www.ldxsolutions.com/wet-esp-flow-direction/ Thu, 24 Oct 2019 20:44:02 +0000 https://www.ldxsolutions.com/?p=6919 Flow direction in a Wet Electrostatic Precipitator (wet ESP) is extremely important. In contrast, flow direction in dry ESPs is of such little importance it isn’t even a consideration; virtually all dry ESPs operate in the horizontal...

The post Wet Electrostatic Precipitator Flow Direction appeared first on LDX Solutions.

]]>

Introduction

Flow direction in a Wet Electrostatic Precipitator (wet ESP) is extremely important. In contrast, flow direction in dry ESPs is of such little importance it isn’t even a consideration; virtually all dry ESPs operate in the horizontal flow mode.
 
Wet ESPs come in various configurations and use round, hexagonal, or square tubes, or plates. In each of these designs the flow direction can vary as upflow, downflow or cross flow. The following discussion will focus primarily on the difference between upflow and downflow. As the reader will see, the implications of this for cross flow are obvious…
 
To read the rest of the article, please submit the form below.

The post Wet Electrostatic Precipitator Flow Direction appeared first on LDX Solutions.

]]>
Regenerative Thermal Oxidizer VS Regenerative Catalytic Oxidizer https://www.ldxsolutions.com/rto-vs-rco/ Thu, 24 Oct 2019 01:49:21 +0000 https://www.ldxsolutions.com/?page_id=6863 Regenerative thermal oxidizers (RTOs) are widely accepted for the control of volatile organic compound (VOC) and hazardous air pollutant (HAP) emissions. Years of experience with this technology...

The post Regenerative Thermal Oxidizer VS Regenerative Catalytic Oxidizer appeared first on LDX Solutions.

]]>

Regenerative Thermal Oxidizer VS Regenerative Catalytic Oxidizer

Introduction

Regenerative thermal oxidizers (RTOs) are widely accepted for the control of volatile organic compound (VOC) and hazardous air pollutant (HAP) emissions. Years of experience with this technology have shown that RTOs can operate very reliably and do an excellent job of destroying VOCs; efficiencies of up to 99% are not uncommon.
 
However, even though RTOs are up to 95% efficient in energy consumption, the cost of fuel in today’s marketplace is a big concern. For example, even at 95% thermal efficiency the temperature rise of the emission stream as it passes through the RTO is approximately 75ºF. With present natural gas price levels in the range of $3 to $4 per MM BTU, a source with 50,000 scfm could cost as much as $250,000 a year to supply with auxiliary fuel.
 
One way of reducing this energy burden is by using catalyst in the regenerative oxidation process. Catalysts work by allowing chemical reactions to proceed at lower temperatures. Thus, the regenerative oxidizer can operate at a much lower temperature with attendant fuel savings.
 
The big question is how do you decide if catalytic operation is appropriate for your emission control application? When does catalytic operation make sense and what pitfalls should be avoided? This paper will outline the important factors to be considered when assessing this economically attractive option…
 
To read the rest of the article, please submit the form below.

The post Regenerative Thermal Oxidizer VS Regenerative Catalytic Oxidizer appeared first on LDX Solutions.

]]>