| Consulting
and Engineering Program for Steel Mill
Client Inland
Steel - Harbor Works
Description ETS was contracted
to execute a major consulting and engineering program for Inland Steel
- Harbor Works coal pulverizing facility to assess the pulverized coal
injection emission control system for a large (10,000 molten tons/day)
blast furnace. The work scope entailed a detailed baghouse and emission
control assessment, an engineering feasibility study of repairing and/or
replacing the emission control system, and options for that design. ETS
was responsible for sizing and specifying the system hardware, including
two 70,000-acfm cyclone precleaners, screw conveyors, and supporting equipment
that was to be engineered into the existing system. The work scope also
included various conceptual baghouse/cyclone designs (including costs),
conveying capacity analysis, system sizing, connecting ductwork and explosion
vent sizing, calculating structural steel loads, structural steel design,
and selecting and developing the instrumentation to ensure reliable system
operations. ETS also assisted in system start-up and troubleshooting.
Baghouse
Design
Client Great
Wall Iron Works, Taiwan
Description Three
new residual oil fired boilers were to be installed at a brewery contracted
by Great Wall Iron Works. The boilers were to be equipped with limestone
injection systems to reduce sulfur dioxide emissions, and the resulting
high particulate emissions required the addition of particulate controls.
Each boiler would operate eight hours per day, exhaust 36,000 acfm at 385°F
with a 480 ppm SO2 concentration, and require 99.5% particulate removal
to meet local emission standards. Because of very limited space for emission
control equipment, a custom-designed baghouse was needed, and a major metal
fabrication facility in Taiwan was retained. In order to obtain the expertise
needed to design the baghouse for this relatively unique application, ETS
was retained by the fabricator.
Because of the space constraints, ETS chose a pulse-jet
baghouse design with five independent filter modules; provisions were made
for both off-line and on-line cleaning. Off-line cleaning was recommended
to enhance removal from the bags of potentially sticky particulates resulting
from incomplete oil combustion. The high exhaust temperature and SO2 content,
combined with the daily start-up and shut-down cycle, meant that the filter
bags had to be designed to withstand temperature extremes and possible
acid attack, in addition to the stresses generated by the pulse-jet cleaning
system. Several filter fabric options including acid resistant woven and
felted fiberglass, aromatic polyimide (P84) and polyphenelyne sulfide (PPS)
were provided to the client.
ETS completed the total design of the baghouses and their
support structures, and provided detailed fabrication drawings for every
aspect of construction of the baghouse. Both the design and the drawing
processes were greatly facilitated by the use of computer-aided design
techniques. ETS also provided specifications for the baghouse components
that would not be fabricated, such as the filter bags/cages, inlet and
outlet dampers, air compressor, and the dust removal system. Additionally,
ETS designed the baghouse control systems and provided drawings and component
specifications for their assembly and operation. Finally, ETS also provided
supporting manuals describing operation and maintenance procedures specific
to this application.
VOC Control
System Specification
Client Midwest
Furniture Manufacturer
Description ETS was contracted
by a large furniture manufacturer in the midwest to research and specify
the best-suited VOC emission control system for their operation. ETS had
previously consulted with this company to resolve a notice of violation
(NOV) for VOC emissions with State and USEPA officials. This client had
neglected to obtain an air permit to construct and operate their three
year old plant (which is the reason they wish to remain anonymous). ETS
was able to successfully negotiate an agreement with the regulators and
avoid fines and significant operating limitations. Using stack test data
and mass balance data, ETS was charged with performing the following tasks:
- Review files and existing data and plant statistics
- Define emission problems
- Identify technically feasible options and alternative
control techniques
- Define budgetary capital and operating costs and expected
delivery
- Solicit vendor inputs to confirm item options and techniques
- Rank control options
- Meet with the client to present findings and recommendations
and define installation requirements.
Pilot
Evaluation of an Iron Foundry
Client Ironton
Iron (Intermet Foundries, Inc.)
Description ETS was contracted
to identify and evaluate technically feasible technologies for control
of visible emissions consisting of particulate and condensible organic
compounds from a cooling process at an iron facility. The multiple-pollutant
nature of this emission stream raised concerns with each available particulate
control as well as with each organic control technology. Although technologies
exist for each of these two types of emissions individually, there is not
single conventional technology capable of treating both types collectively.
Having exhausted conventional control options, our study led us to consideration
of an emerging control technology using carbon injection with a baghouse.
This consideration was reinforced when it was learned a similar emission
stream was causing operating problems with a baghouse from condensation
of the organics.
A four-week pilot evaluation was conducted using a dry-injection
feeder and baghouse treating a similar emission stream. The BPMES
was used to monitor, collect, and organize baghouse performance data. Commercially
available bag precoat material and powdered-activated carbon were injected
over a range of feed rates. Although both types of injected material resolved
the condensation problem with the baghouse, the use of carbon completely
eliminated the visible emissions. Foundry personnel continue to use the
lower-cost precoat material to solve the condensation problem while saving
more than $100,000 per year in maintenance costs. The regulatory agency
is reviewing the need to require carbon-injection for further control of
the organics.
Removal
of Dust-Collection System at a Tire Retread Facility
Client Bandag
Incorporated
Description ETS was retained
by Bandag, Inc. to conduct an engineering evaluation on its Tread Grinding
Dust Collection System and to identify and design a system that would improve
dust pickup at the buffing stations, and at the same time reduce the potential
for fires in the system baghouse. The engineering evaluation of the existing
dust collection system included the following:
- Buffer station gas volume measurements and experiments
to determine the gas volume that provides satisfactory dust pickup
- Determination of baghouse inlet dust loading, gas volume,
static pressure, and dust particle size distributions
- Ductwork structural evaluation
- Baghouse structural evaluation
- System fan evaluation and analysis of various upgrade/replacement
options.
Ultimately, ETS outlined specifications to describe the
general qualities, performance, and basic systems required in the fabrication
and construction of the finishing line modification. The system modification
involved replacing an existing spark arrestor with a medium-low energy
cyclone, replacing the existing fan with a larger fan with improved system
entry, and recommending fabric types to provide superior resistance to
burning with Hysil used as a precoat. Included in the specifications were
identification of all labor, materials, equipment, tools, supplies, taxes,
and services required for construction activities, such as:
- Demolition and removal of existing ductwork from above
buffing hoods to baghouses, including spark arrestor boxes and ductwork
support
- Demolition and removal of ductwork from baghouses to
fans and fan discharge duct
- Constructing two foundations and making roof penetrations
for two new columns
- Installing new structural steel platform framing in cyclone
area
- Removing fans and motors
- Removing platform and decking handrail
- Installing new motor and fan support framing and deck
extension framing.
Turnkey
Dust Handling and Control System
Client Boxley
Quarries
Description ETS was retained
by a large rock quarry operation to design a turnkey crushed stone transfer
and air pollution control system. The work scope included design, specification,
fabrication and installation of appropriate screw conveyors, belt conveyors,
dust supression systems and a 25,000 acfm fabric filter control system.
This system allowed the client to meet the federal and state air pollution
standards for both point source and ambient dust.
BPMES
Installation
Client Lonestar
Steel Co.
Description Lonestar Steel
had just purchased a used reverse air baghouse and was in need of an instrumentation
system that would fit this application. In addition to monitoring standard
baghouse parameters, they wanted to be able to track other process-related
parameters and have real-time alarms warn them if any parameter exceeded
certain set-points. Based on its capabilities and competitive pricing,
Lonestar Steel chose the BPMES. The real-time alarm
feature was added to fit their needs and serves as a general upgrade to
be available for future BPM systems. The Lonestar Steel BPM system was
configured as a standard Model V. By using their own PC and by using a
direct, PC-to-BPM connection, Lonestar was able to keep instrumentation
costs to a minimum.
BPMES
Custom Modification
Client Baltimore
Gas & Electric - Crane Station
Description The Crane
Station Baltimore Gas and Electric (BG&E) power plant has been using
two ETS patented Baghouse Performance Monitors to monitor their large reverse-air
baghouses since the late 1980s. Although the existing BPMES
"stepping modes" were generally adequate for most monitoring
needs, the plant engineer had started to rely on the BPM's capability to
follow and monitor the cleaning cycle from compartment to compartment.
Unfortunately, this capability relied on tubesheet pressure drop signals
as feedback to determine when a particular compartment is cleaning, and
if any compartments were ever put off-line, the BPMES could be "confused".
In early 1993 the plant engineer decided to eliminate this problem, and
he contracted ETS to make the appropriate modifications. The resulting
changes now allow the system to correctly follow the cleaning cycle and
to identify (by number) exactly which compartment is being cleaned, and
which compartments are off-line. BG&E can now use feedback from damper
actuators rather than pressure signals to intelligently follow the cleaning
cycle. This new mode of operation can now be made available to future BPMES
customers as a standard option.
Obtain
Permit to Construct and Operate
Client Anonymous
Concrete Manufacturer
Description ETS was retained
by a national concrete and polymer concrete manufacturer to obtain state
permits to construct and operate a polymer concrete plant after the fact.
An initial background study of the case revealed that the plant had been
operating for two years without a permit. The obvious task was to obtain
an operating permit and bring this source into compliance.
To accomplish this, ETS did the following:
- Performed EPA emission tests for particulate and volatile
organic compounds
- Performed the necessary input-output calculations to
determine air pollutant emissions from the plant stacks not tested
- Acted as liaison between the state Air Pollution Control
Board and the client, including representing client during meetings with
state
- Completed proper state permit forms to construct and
operate the source.
Assessment
of an Air Pollution Control Technique Serving a Complex Chemical Process
Client E.
I. DuPont de Nemours & Company, Inc.
Description ETS
was retained by a major chemical company to assess the air pollution control
equipment of a catalyst production process. The system was plagued with
visible emissions and was a constant source of complaints from local enforcement
agencies. A program was agreed upon that included the following main tasks:
- Problem definition and profile of emission chemistry.
- Selection of alternative control techniques.
- Specific recommendations - including equipment specification
and recommended operation.
The project was a success due to ETS's ability to first
define the problem and then apply basic chemical engineering principles.
ETS recommended a solution to achieve the program goals.
Improvement
of Baghouse Performance
Client Union
Chemical Division of Union Oil
Description Union Chemical
Division of Union Oil retained ETS to improve the performance of a baghouse
servicing a waste heat boiler with the problem of premature bag failure
and high emission rates. An investigative program was initiated to determine
the cause of the extremely premature failure. Operation and maintenance
procedures were reviewed, process and flue gas parameters were monitored
and documented, ash samples were analyzed and further analysis of the used
fabric was conducted. It was determined that the process produced a highly
corrosive material which, when introduced to the fabric, would quickly
degrade the finish of that fabric. Once the finish was degraded, the bags
would then abrade rapidly to deterioration. A scanning electron microscope
(SEM), along with the other physical tests, provided excellent commentary
on the rate of deterioration with on-stream time. A program was implemented
to screen alternative fabrics for this application. Six candidates were
selected and installed in the baghouse and subjected to normal operating
conditions. The candidate bags were extracted periodically, tested and
their results compared. From the screening program, a fabric was identified
that would operate reliably in this most severe atmosphere. Bag life has
been improved from a matter of months to over a year.
Baghouse
System Upgrade
Client Kerr
Industries
Description The fabric
finishing division of this Fortune 500 company had a baghouse operating
on a coal-fired boiler. ETS was involved in upgrading the overall capability
of the baghouse system. This application had been plagued with high system
pressure drop. The causes for excessive pressure drop were numerous, including
insufficient bag cleaning, poor coal quality, improper boiler operation,
and, at full load conditions, excessive gas-to-cloth ratio. Improvements
were made to the cleaning system and alternate fabrics were screened to
determine their capability to operate effectively at extremely high gas-to-cloth
ratios (>8:1). Tremendous improvements were made and the system in now
able to operate at full boiler load conditions.
Engineering
Evaluation, Testing, and Expert Witness
Client Anonymous
Description ETS was retained
as an expert witness by a major steel manufacturer for problem assessment
and testimony. The client was operating a pulse jet baghouse for control
of particulate emissions from an electric arc furnace. The system was designed
to handle 100,000 acfm, but due to excessive pressure drop could handle
no more than 80,000 acfm. To date, ETS has researched this problem, including
conducting a detailed data and inspection review, an engineering evaluation
with economic analyses, and issuance of a report discussing the problem
assessment and solutions to the problem.
Baghouse
System Upgrade
Client Titan
Description ETS was retained
by a leading cement manufacturer to improve the performance of a large
clinker cooler baghouse system. The operation was plagued with high emission
rates and premature fabric failure. ETS was able to identify the causes
and recommended a list of solutions, including modification of bag construction
and baghouse system components. ETS was given the contract to engineer
and supervise the implementation of these modifications. The end result
is that the system is operating reliably with no emission problem, and
bag life has been increased from less than one to more than three years.
The client was so pleased with ETS's work, they contracted
ETS to upgrade their finish mill and row mill baghouses. ETS has also performed
numerous diagnostic and compliance tests along with trial burn emission
tests for this client over the last 20 years.
Full-Scale
Demonstration of a High-Velocity Fabric Filter System Used to Control Fly
Ash
Client USEPA/IERL
Description A full-scale
investigation was conducted (following a pilot plant study) of applying
high-velocity fabric filters to a coal-fired boiler for fly ash control.
Two filter systems (using different filter media) were installed separately
on two 60,000 lb steam/hr coal-fired boilers. The performance of the fabric
filters was evaluated over a one-year period to determine total mass removal
efficiencies and fractional efficiencies.
|
