# BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS

Authors: Criag H. Fleming, Gary D. Mooney
Clyde Bergemann Delta Ducon, Malvern, PA 19355 USA

Published at:
Power-Gen International Orlando, FL USA December 14-16, 2010BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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INTRODUCTION

Wet Bottom Ash material handling system s and surface impoundments are presently regarded as the industry standar d and are certainly the most commonly used method in the coal fired power industry around the world today. However, with the recent event of an ash pond (surface impoundment) failure and the ensuing EPA investigation of all existing facilities employing this technology, environmentally suitabl e alternatives are being investigated by coal fir ed electric power producers.

This paper will address the available technol ogies and their comparison. The four primary Bottom Ash conversi on approaches are as follows:

 DRYCONTM SYSTEM: (retrofit) The colle ction, crushing, air cooling and mechanical conveying of bottom ash without the need for water quenching.

 SUBMERGED SCRAPER CON VEYOR: (retrofit) The collection, water quenching and mechanical conveying of bottom ash; with a closed loop cooling water system.

 CONVENTIONAL TANK FARM DEWATERING: The continued collection of bottom ash in water impounded hoppers, and the future addition of dewatering bins, settling tank and surge tank; with a closed loop water system.

 ASHCONTM REMOTE SUBMERGED S CRAPER CONVEYOR SYSTEM: The continued collection of bottom ash in water impounded hoppers, and the future addition of a hybrid Subm erged Scraper Conveyor; with a closed loop water system.

This paper will detail the following for each of the four conversion options:

 Site Specific Limitations: Facility Age, Physical Lay out, and Boiler design type and configuration.

 System Design Parameters: Thermal and Mechanical.

 Environmental Issues and Benefits: Zero water discharge and Boiler Efficiency improvement.

 Economic analysis, of each approach.

Conversion projects will differ from plant to plant and variations on the systems will be discussed.

Clyde Bergemann is recognized as a technical leader in the field of Bottom Ash and Fly Ash Handling Systems and has many refer ence installations around the world.BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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Wet Bottom Ash (BA) material handli ng systems and surface impoundments are presently regarded as the i ndustry standard and are certai nly the most commonly used method in the coal fired power industry around the world today.

Water impounded bottom ash hoppers, located under the boiler throat are used to store the collected bottom ash and periodically (once or twice per 8 hour shift) the hoppers are discharged and Bottom Ash is hydraulically conveyed to surface impoundments (ash ponds). The ash is pumped utilizing either high pressure jet pumps or slurry pumps.

Surface Impoundment are large water filled basins, either man made or constructed using natural topography and the employ ment of a retainage dam, to store the coal combustion residuals (CCR) for extended periods of time.

At the time when many surface impoundments were constructed there was little state or federal regulation.

However, with the rec ent event of an ash pond (surface impoundment) failure and the ensuing EPA investigation of all existing facilities employing this technology, environmentally suitable alternatives are being investigated by coal fired electric power producers.

As of the date of prepar ation of this paper, there were 162 Power Plants utilizing Surface Impoundments. Recently the US EPA is proposing to regulate CCR under one of two scenarios. high water level

normal water level

mean ash level

jetting nozzles

sluice gate & access door clinker grinder

weir box high pressure water inlet jet pump / eductor Figure 1: Typical Bottom Ash Hopper Arrangement

Figure 2: Typical Surface Impoundment (Ash Pond)

Figure 3: Typical Surface Impoundment after berm failureBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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The Environmental Protection Agency (EPA) is proposing to regulate for the first time, Coal Combustion Residuals (CCRs) under the Resource Conservation and Recovery Act (RCRA) to address the risks from the disposal of CCRs generated from the combustion of coal at electric utilities and independent pow er producers. However, the Agency is considering two options in this proposal and, thus, is proposing two alternative regulations. Under the first proposal, EPA would reverse its August 1993 and May 2000 Bevill Regulatory Determinations regarding coal combustion residuals (CCRs) and list these residuals as special wastes subject to regulation under subtit le C of RCRA, when they are destined for disposal in landfills or surface impoundments. Under the second proposal, EPA would leave the Be vill determination in place an d regulate disposal of such materials under subtitle D of RCRA by issuing national minimum criteria. Under both alternatives EPA is proposing to establis h dam safety requirements to address the structural integrity of surf ace impoundments to prevent catastrophic releases. Following is a summary of the two proposals.

Figure 4: Proposed CCR Regulatory Differences
http://www.epa.gov/epawaste/nonhaz/industrial/special/fossil/ccr-rule/ccr-table.htmBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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In most cases, under the current proposed regulatory scenarios, surface impoundments will no longer be a vi able disposal option. This paper will address the available technologies and their comparison for elimi nating the need for surface impoundments. The four Primary Bottom Ash Conv ersion approaches are as follows:

 CONVENTIONAL TANK FARM DEWATERING: The continued collection of bottom ash in water impounded hoppers, and t he new addition of dewatering bins, settling tank and surge tank; with a closed loop water system

.

 SUBMERGED SCRA PER CONVEYOR: (retrofit) The collection, water quenching and mechanical conveying of bottom ash; with a closed loop cooling water system.

 REMOTE DEWATERING CO NVEYOR SYSTEM ASHCONTM : The continued collection of bottom ash in water im pounded hoppers, and the added integration of a hybrid Remote Dewatering Conveyor ; with a closed loop water system.

 DRYCONTM SYSTEM: (retrofit) The collection, crushing, air cooling and mechanical conveying of bottom ash without the need for water quenching.

This paper will detail the following for each of the BA conversion options:

 Site Specific Limitations: Facility age, physical layout, and boiler design type and configuration.

 System Design Parameters: Thermal and mechanical.

 Environmental Issues and Benefits: Zero water discharge and boiler efficiency improvement.

 Economic analysis, of each approach.

Conversion projects will differ from plant to plant and variations on the systems will be discussed.BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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 Conventional Dewatering Systems:

When new power plants were being designed in the 1970’s, the state of the art ash handling systems at the time we re closed loop water recirculat ion systems that involved a “tank farm” thousands of feet away from the boiler.

Figure 5: Conventional Bottom Ash Dewatering System

In these systems the bottom ash was pumped from the ash hoppers to the top of tall dewatering bins using either je t pumps or centrifugal slurry pumps. In either case, the Total Dynamic Head, TDH, that these pumps were designed to overcome included the height of the dewatering bins as well as the horizontal distance to the location of the bins. This vertical lift was a significant number and led to the phase out of jet pumps for these closed loop systems in favor of high-head single stage mining pumps to handle the high TDH as well as the larger slurry flows associated with greater ash generation rates.

When the bottom ash slurry is pumped to the top of the dewatering bins, it is discharged into one of two bins: one bin is always ready to receive slurry while the other may be offline and in the midst of a 4-8 hour decanting cycle. All of t he water entering or decanting from any dewatering bin overfl ows by gravity to a settling tank that reduces the Total Suspended Solids, TSS, and returns collect ed sludge back to an av ailable dewatering bin. The clearer water overflowing the settli ng tank is stored in a surge tank for eventual return to the ash hopper to fo rm the closed loop. There is still some ongoing particulate settling in the bottom of the surge tank whic h is also returned to an available dewatering bin. The actual discharge point from the surge tank for the closed loop recirculation path is above the lower settling zone.BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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The dewatering bins themselves have an upper portion with an inlet baffle, underflow baffle and overflow weir to force the ash itse lf down into the lowe r collection cone while providing a tortuous path for the water that reduces the ash carryover to the settling tank as much as possible, giv en the high flow rates.

Once the incoming slurry flow to the dewater ing bin ceases and the ash level is above the conical section, lower decanting valves ar e opened which allow wa ter trapped in the ash volume to work its way by gravity out of t he interstitial voids in the ash to decanting screens along the walls and possi bly center of the bins. These screens have small openings to hold the ash in the bin while t he water passes through them and down to a collecting ring header and out through the dec anting valves to the settling tank.

The settling tanks have to be quite large, on t he order of 50 to 75 feet diameter, to slow the water flow velocity rates down and allo w the ash fines to settle to the bottom. Underflow baffles and weirs ar e used here also to reduce the ash carryover to the surge tanks.

 CONVENTIONAL TANK FARM DEWATERING:

Where the boiler house config uration or type of boiler technology employed (cyclone boilers), prohibits the use of under the boiler retrofit technologies, the use of Conventional Tank Farm Dewatering can be utilized.

Figure 6: Conventional Bottom Ash Dewatering System as Retrofit

If the bottom ash currently is pumped to an ash pond, a complete closed loop water recirculation system can be erected in a field along the path of the existing ash lines and two diverter valves installed during a very short outage to divert the ash away from the pond and into the new closed loop system.BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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From a design standpoint, however, the biggest i ssue is replacing the low TDH capability of any existing jet pumps or even slurry pum ps to handle the new vertical height and increased TDH of a closed loop system. This involves chang ing the water supply pumps and increasing the horsepow er of their motors.

 SUBMERGED SCRAPER CONVEYOR (Retrofit)

Another viable option for Bottom Ash Handli ng is to utilize Submerged Scraper Conveyor (SSC) technology. For most Pulverized Coal (PC) fired boilers and some cyclone fired units it is possible to retrofit the bottom of the boiler with a Submerged Scraper Conveyor. However, for stations with multiple adjacen t units, the physical a rrangement of existing equipment may prohibit use of this technology, as the inclined dewatering section has no place to exit the boiler house.

The SSC is a heavy duty dual drag flight chain conveyor. The conveyor is submerged in a water trough below the furnace which quenches hot bottom ash as it falls from the combustion chamber. The bottom ash is then dewatered as it trav els up the inclined section before it discharges. Double roll crushers can be used for final particle reduction at the discharge of the SSC. The discharge of the SSC can be fed into removable containers or onto a transfer conveyor, which transports the Bottom Ash to storage, for by-product reuse or landfill. The SSC can be driven via single or twin hydraulic or electro-mechanical drives to su it the application r equirements. Optional discharge Slide Gates can be provided depending on the app lication requir ements, and removable or static conveyor s can be engineered to suit bo iler geometry or operational requirements.

The final Bottom Ash moisture content is generally between 15 to 20 percent. If new regulations require further dewatering, the SSC can be discharged to a dual dewatering bin arrangement to further reduce the BA moisture content.

To achieve “zero discharge” (water) for an SSC system, a “closed loop” water system can be installed. In order to minimize corrosi on, water treatment for pH control and heat exchangers may need to be included as part of the total system. This adds additional capital cost and operating cost

. Figure 7: SSC Factory Assembled for Testing

Figure 8: SSC Discharging to Dewatering BinsBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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 REMOTE DEWATERING CONVEYOR SYSTEM

ASHCONTM Remote Submerged Scraper Conveyors:

Clyde Bergemann Delta Ducon, CBDD, now offers a unique way to allow plants to retain all of their existing tradi tional wet bottom ash hoppers and slurry systems and still eliminate their ash ponds. By intercepting the pipelines leading to the ash ponds, the slurry flow is diverted to an ASHCONTM Remote Submerged Scraper Conveyor that has all of the bottom ash dewatering characte ristics of a regular Submerged Scraper Conveyor plus the water flow control aspect s of a dewatering bin without requiring the height of traditional dewatering bins.

Figure 9: ASHCONTM Remote Submerged Scraper Conveyor as Retrofit

By staying close to the ground, there is littl e, if any, increase in Total Dynamic Head, TDH, requirements on the existing jet pumps and water supply pumps associated with the existing pond disposal system. Rather than retrofitting jet pumps and water supply pumps to lift the slurry high in the air to reach new dewatering bins, the ASHCONTM Remote Submerged Scraper Conv eyor easily accepts what exists and continuously dewaters the ash to the commercially required le vel of dryness. The resultant bottom ash product can immediately be loaded on to trucks for off site disposal or stored in temporary piles on the ground. The overfl ow water is handled by traditional or more state-of-the art water clarifiers. From Existing Bottom

Ash System New ASHCON TM

System

Existing Ash Pond Existing Bottom Ash Line to Ash Pond 

### PATENT PENDING

Diverter Valves to new

ASHCON TM From Existing Bottom

Ash System New ASHCON TM

System

Existing Ash Pond Existing Bottom Ash Line to Ash Pond 

### PATENT PENDING

Diverter Valves to new

ASHCON TMBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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The ASHCONTM RSSC Advantage

The continued use of the entire ash hopper syst em with seal troughs, gates, grinders, jet pumps and water supply pumps means many of the advantages of a true SSC retrofit cannot be realized but adding a Remote SSC as opposed to traditional water recirculation tanks with dewatering bins, settling and surge t anks, allows the plant to eliminate the pond and save costs. T hese benefits include;

 The ability to retrofit to multiple existing Units and remove the ash pond disposal without interfering with the boi ler islands. Multiple Units can use

one ASHCONTM

.

 Lower power consumption than with a traditional water recirculation system with tall dewatering bins starting with sa vings with the initial water supply
pumps.

 Simplified process complexity: onl y one continuous conveyor is used instead of two batch-type dewatering bi ns to reach the same level of dryness.

 Lower operational and maintenance costs than traditional water recirculation systems.

Figure 10: ASHCON TM Remote Submerged Scraper ConveyorBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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The ASHCONTM compared to an SSC

Both a traditional SSC and an ASHCONTM Remote SSC is used for the continuous removal of bottom ash from conventional Pulv erized Coal fired boil ers and are particularly well suited when high ash generat ion rates are expected. Bo th conveyors are capable of quenching, dewatering and transporting high rate s of ash and offer greater energy efficiency than hydraulic systems of comparabl e capacity. Factory assembly and a trial prior to shipment ensures an accelerated installation and start-up program, avoiding timely delays.

The differences start with the lo cation of the conveyor relative to the boiler. An SSC located under a large Pulverized Coal fir ed boiler has to be designed for the potential of large slag falls associated with some coals and certain events such as boiler cleaning with soot blowers. This leads to additional structural steel beyond what is needed for the conveyor function itself. The ASHCONTM Remo te SSC, by contrast, receives bottom ash that has already passed through a grinder and there is very little vertical drop down into the conveyor water trough. This leads to much longer conveyor life and reliability.

A typical SSC only requires 35-50 GPM conti nuous water input to maintain water level and temperature in the water trough. Often th is water supply service is intermittent and assisted by cooling water from the associat ed mill rejects/pyrites system. An ASHCONTM Remote SSC, by contrast, needs to receive and ha ndle all of the dilute water slurry in the existing pipeline system. This flow can be several thousand gallons per minute, GPM. But this flow is the same flow that has been addressed and handled by dewatering bins for many years. By placing the same amoun t, or more, of overflow weir length used by circular dewatering bins all along both sides of the ASHCONTM Remote SSC, the incoming water is easily drained off while the bottom ash continues up the conveyor incline.

Figure 11 : ASHCON TM RSSC Design ConceptBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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When contemplating the removal of an ash pond serving several boilers, the cost of individual SSC's and boiler outages, including dem olition of existing tr aditional equipment can be financially prohibitive especially fo r older Units. A si ngle ASHCONTM Remote SSC merely has to be erected on open land and can serve many Units, usually receiving ash from one Unit at a time or as they are already grouped together in common pipelines.

Figure 12: ASHCON TM Remote Submerged Scraper Conveyor RetrofitBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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 DRYCON TM SYSTEM (retrofit):

DRY vs. WET

Traditionally bottom ash has been handled in a wet condi tion utilizing established technologies such as water impounded hop pers or submerged scraper conveyors. The use of water as opposed to air as a cooling agent incurs additional costs. Factors such as water treatment, corrosion damage, higher di sposal costs and environmental problems as well as the higher cost of operation and maintenance must all be considered. Using a dry system means that no water is required in the proc ess, therefore no water treatment is necessary. Reduced emissions and returning the rmal energy to the boiler results in lower coal usage, which means fewer emissions to produce the same electric power. The table below shows the main factors which compare between the two methods of conveying:

WET ASH HANDLING DRY ASH HANDLING

 Cooling water requirements  No water requirement

 Water treatment & environmental issues  No water treatment

 Significant energy loss  Reduced thermal energy losses

 Corrosion damage  Reduction of unburned carbon (LOI) and contribution to energy
recovery

 Steam is produced escaping into the boiler house area  Improvement in boiler efficiency

 Higher disposal costs  Easier compliance with the environmental protection regulations

 Maintenance intensive  Marketable ash quality  better
ash sales

 Significant energy consumptionBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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The DRYCON TM system is installed below the boile r fully sealed to the combustion chamber. The negative pressure inside the boiler sucks air, in a controlled manner, (predominately at the top end of the DRYCON TM ) into the bottom ash conveyor system. The air moves counter flow direction along the surface of the ash which rests on the conveyor pans. This activates a reburning proc ess of the glowing as h, which reduces the

unburned carbon level and fr ees up additional thermal energy. The air is heated up before it enters the combustion chamber and adds additional thermal energy to the steam generating proc ess inside the boiler. Approximately 1% of the tota l combustion air is required for the dry cooling system and can be considered as a constant value in the boiler des ign. This ensures that the combustion process and t he exhaust gas composition are not affected.

THE ARRANGEMENT

Underneath the combustion chamber a transit ion chute or hopper is installed and supported from the floor by means of a steel structure. The transit ion chute or hopper is lined with special refractory and insulation at the inside to withstand the radiation from the combustion chamber of the bo iler. As a standard a heat resi stant fabric or HT metal compensator (expansion joint) is insta lled between the boiler/hopper outlet and the DRYCON TM intake, to compensate the movement bet ween cold and hot condition of the boiler. The compensator is fabr icated from elastic metal, re sistant to high temperatures. To avoid damage due to high temperatures by the radiant heat from the combustion chamber, a special protective skirt with lining is provided at the inner side of the compensator. The compensator will be delivered and mounted in one piece only, to assure tightness and the r equired flexibility. Figure 1 3 : DRYCON Cooling Air Flow

Figure 14 : DRYCON Installed

Under the Boiler DischargeBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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KEY DESIGN FEATURES

DRYCON TM utilizes many key features which cont ribute to the technology’s success in the market. The conveying design is similar to proven SSC systems, employing many of the SSC components:

Chain And Sprocket Wheel – the sprockets are manufactured from wear resistant materials and have exchangeable pockets for easy replacement.

Tension And Drive Stations –The tension roller is mounted with lubricated long life heavy duty roller bearings. Tension is applied via manually or automatica lly operated hydraulic cylinders.

Supporting Idler – mounted on close centers and lubricat ed, manually or automatically, with hear resistant grease, the ro llers can be replaced from the outside whilst the boiler is still on

‐ line.

Fines Recirculation – the system is self cleaning wit h the integration of a fines

re

‐ circulation plates.

Impact Beams – impact beams have been designed into the conveyor casing to withstand any loads imposed from large slag falls ensur ing that the drive el ements are not damaged

Jaw Crushers – large slag material can be broken down by jaw crushers in order to ensure they are an appropriate size to be cooled and conveyed.

Safe Monitoring – should a blockage occur, the drive motor stops immediately then enters a removal procedure before giving an alarm to the control room.

Figure 15: DRYCON Assembled for Factory TestingBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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 BOTTOM ASH CONVERSION TECHNOLOGY SELECTION

To determine which of the Bottom Ash conv ersion technologies presented herein may be a consideration for your power plant, a detaile d investigation of your facility will be necessary. The following summarizes t he key impacts of the technologies.

Figure 16: Bottom Ash Technologies Comparison BA CONVERSION SELECTION COMPARISON CONVENTIONAL TANK
FARM DEWATERING REMOTE DEWATERING CONVEYOR SYSTEM -

ASHCON TM SUBMERGED SCRAPER CONVEYOR (SSC) DRYCON TM SYSTEM

Physical Layout No Major Change Required within the
boiler house No Major Change Required within the boiler
house Removal of existing BA Hopper and conveying system with retrofit
under the boiler. Removal of existing BA Hopper and conveying system with retrofit
under the boiler.

PC Applicable for most units Applicable for most units Applicable for most units Applicable for most units

CYCLONE Applicable for most units Applicable for most units Not Applicable (generally due to space limitations) Not Applicable (Boiler is Wet Bottom)

Surface Impoundment Elimination Yes Yes Yes Yes

"Zero Discharge" (Water) Closed Loop System - pH Conditioning required Closed Loop System - pH Conditioning required Closed Loop System - pH Conditioning and Heat Exchangers may be required Not required - No water is used in the System

0&M Cost Impact ~25 to 30 % Increase
with the addition of the Tank Farm Dewatering ~5 to 10 % Increase with
the addition of the
ASHCON ~30-35% Decrease with
SSC ~40-50% Decrease with
DRYCON

Energy Consumption ~80 to 90 % Increase
with the addition of the Tank Farm Dewatering ~15 to 20 % Increase with
the addition of the
ASHCON ~45-55% Decrease with
SSC ~60-70% Decrease with
DRYCON

Boiler Efficiency No Change No Change No Change 0.02% TO 0.07% Boiler Efficiency Increase Energy Efficiency Considerations:

Boiler design type Site Specific Limitations:

Environmental Considerations:

Maintenance Budget Considerations:BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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 ECONOMIC COMPARISON:

Following is an estimated financial comparison of the technologies over a ten year period of operation. A typical 500 MW Unit, with a current Surface Impo undment operation was considered for this analysis.

Items included in this analysis are:

 Ten Year Capital Cost Amor tization (“Turnkey Project”)

 Operation and Maintenance Costs

 Electric Power Costs

 Boiler Efficiency Improvement (Fuel Savings)

Figure 17: Bottom Ash Technologies Economic Comparison TYPICAL 500 MW BOTTOM ASH CONVERSION COMPARISON

$0 $250,000 $500,000 $750,000 $1,000,000 $1,250,000 $1,500,000 $1,750,000 $2,000,000 $2,250,000 $2,500,000 $2,750,000 $3,000,000 $3,250,000 $3,500,000 $3,750,000 $4,000,000 $4,250,000

1 2 3 4 5 6 7 8 9 10

YEARANNUAL EQUIVALENT COST INCLUDINGTEN YEAR CAPITAL COST AMORTIZATION

CONVENTIONAL ASHCON SSC DRYCONBOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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Clyde Bergemann Delta Ducon is a leading s upplier of material handling systems and components, handling such products as ash, coal, sand, carbon, gypsum, limestone, lime, and other materials.

Established in 1925, and currently located in the Philadelphia suburb of Malvern, PA, Clyde Bergemann Delta Ducon is a member of the Clyde Bergemann Power Group meeting the needs of a global cl ient base, while continually expanding and refining its technological expertise.

Especially notable is the co mpany‘s long-standing environment al focus, which began well before the initiation of federal regulations in the 1970’s. Pat ented technology for material handling helps to maintain EPA requirements for emissions control and clearly sets Clyde Bergemann Delta Ducon apart in markets dealing with abrasive substances such as ash, limestone and coal.

Clyde Bergemann In c. is a member of Clyde Bergemann Power Group , the leader in supplying boiler cleaning and ash handling solu tions worldwide. The Clyde Bergemann Power Group has factories and representative offices in sixteen countries supplying and supporting vital equipment and systems for im proving boiler performance in various industries worldwide.

Clyde Bergemann has become the world leader in on-line boiler cleaning equipment by integrating and enhancing boiler cleaning technologies from around the world. Our product lines combine the experience and know ledge developed over the last 100 years by various independent sootblower brands such as Clyde, Bergemann, Copes Vulcan and Forest. Each of these independent com panies developed expertise in the very specialized field of on-line boile r cleaning. All this experienc e has been combined to form the Boiler Efficiency Division of the CBPG to provide boiler operators and manufacturers with optimum solutions for improving boiler efficiencies.

Clyde Bergemann, Inc., the US operation of Clyde Bergemann, was established in 1988 as Bergemann USA, Inc. by Bergemann GmbH, a subsidiary of Deutsche Babcock (later Babcock Power), both German based. Ber gemann GmbH - a specialist in cleaning systems for boilers - had been in the boiler cleaning business for several decades.

In 1996 Clyde Blowers PLC of Glasgow/Scotland, which was active in the same market segment, acquired the Bergemann Gr oup and the company was renamed Clyde Bergemann, Inc. Clyde Blower s had been in the boiler cleaning business for many years. In the 1990s the product line was extended in to the field of ash handling equipment.

Since that time additional mate rials handling activities were incorporated. Thus, the Clyde Bergemann Power Group was form ed with 16 subsidiaries worldw ide and activities in the following market segments:BOTTOM ASH CONVERSION OPTIONS AND ECONOMICS 

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 cleaning systems for heati ng and reaction surfaces

 ash handling equipment and conveyor systems

 exhaust gas and exhaust air cleaning systems

 combustion air systems

 complete after-sales service

 optimization technology