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GALLERIES
WASTEWATER TREATMENT
PLANTS:
Dutchland, Inc. specializes in
design/build or build to specification precast
concrete wastewater treatment plants.
Following is a list of
wastewater treatment plants as designed,
manufactured and constructed by Dutchland,
Inc.:
Extended Aeration Wastewater
Treatment Plants including Package and customized
Norweco™ Wastewater Treatment plants and
Customized Precast Post-Tensioned Wastewater
Treatment Plants
Sequencing Batch
Reactors
Small Flow Wastewater Treatment
Plants (500 GPD, 750 GPD, 1,000 GPD, 1,250 GPD, and
1,500 GPD)
We
can provide prints & specs for our
products
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NORWECO
SINGULAIR SMALL FLOW WWTP (500-1,500 GPD)
PHOTO GALLERY
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SMALL FLOW WASTEWATER
TREATMENT PLANTS:
In recent years, a much greater
demand for Small Flow Wastewater Treatment Plants
has surfaced. Dutchland, Inc. manufactures and
delivers (and assembles if desired) the
Norweco™ Singulair Model 960 designed to treat
500 GPD, 750 GPD, 1,000 GPD, 1,250 GPD, or 1,500
GPD. This Small Flow Treatment Plant is one of the
few that has a Class I rating by the NSF (National
Sanitation Foundation).
The PA Department of
Environmental Protection (as in other states) has
become considerably more receptive to permitting a
Small Flow system in areas where the percolation
rate is not adequate for standard subsurface
discharge. Dutchland, Inc. has constructed many of
these plants. Typical installations
include:
- Subsurface Discharge (drain
field or sand mound)
- Stream Discharge
- Spray Irrigation
The distinct advantages of
Norweco™ Model 960 Small Flow Plants are as
follows:
- When discharging into a
drain field or sand mound, the size of the drain
field or sand mound can typically be reduced by
1/3 the normally required size.
- Ammonia Nitrogen is greatly
reduced. Additional information is available
upon request regarding the reduction of Ammonia
Nitrogen.
- When discharging into a
drain field or sand mound, the owner will find
that the drain field or sand mound will not need
to be replaced (if the plant is operated
properly) versus the temporary life of a drain
field or sand mound if septic waters are
discharged into the receiving area.
- This type of plant is
relatively inexpensive. Even a tertiary model
costs little more than the cost to construct a
sand mound.
All tanks are constructed of
high strength precast concrete to increase the life
of the structures. As of early 1993, the PA
Department of Environmental Protection has mandated
that 80 square foot of sand filtration be provided
for 400 gallons per day when discharging into a
stream, even if the NPDES Permit limitations are
secondary. Dutchland, Inc. includes a filter that
provides 92 square foot. These systems meet the
criteria as required by the PA DEP Guidelines For
Design Installation and Operation of Small Flow
Sewage Treatment Facilities.
We
can provide prints & specs for our
products
NORWECO EXTENDED AERATION
WASTEWATER TREATMENT PLANTS:
Dutchland, Inc. has designed,
manufactured and installed Norweco™ wastewater
treatment plants since 1981. This type of
wastewater treatment plant consists of modulithic
tanks typically all of the same size and depth. The
tanks are 15 ft. 8 in. in length x 6 ft. 10 in. in
width and can be 10 ft. 0 in., 12 ft. 4 in. or 14
ft. 8 in. deep and are equipped with integral
walkways for access to any part of the plant. The
nominal wall thickness is 4-3/4 in.
This plant is very economical to
construct, assemble, and expand in the future.
Norweco™ wastewater treatment plants as
manufactured by Dutchland, Inc. typically are
equipped with Equalization, Aeration, Clarifiers,
Disinfection (chlorination and dechlorination or
ultraviolet disinfection), Polishing Clarifier,
Post Aeration, Sludge Holding (and/or Tertiary
filtration and denitrification if required).
Typically, these plants are buried in the ground
with approximately 4 in. above finished grade, and
have the equalization and sludge holding tanks
encased with anti-buoyancy collars to prevent
flotation during empty tank and saturated soil
conditions. All equipment in the wastewater
treatment plant is removable from the top of the
plant so there is no need to dewater any portions
of the wastewater treatment plant. The plant can be
finished with galvanized steel, aluminum grating,
or aluminum hand rail on the top.
We
can provide prints & specs for our
products
CUSTOM PRECAST
POST-TENSIONED
EXTENDED AERATION WASTEWATER TREATMENT
PLANTS:
Details
of Flat Wall Post-Tensioned
Tanks
(PDF)
Post-Tensioning
Defined, by the Post-Tensioning Institute
(PDF)
Dutchland, Inc. fabricates
customized extended aeration wastewater treatment
plants with precast, post-tensioned concrete walls.
This type of system is generally designed for
treatment plants above 100,000 gallons per day,
however it has been used in wastewater treatment
plants as small as 25,000 gallons per day. The
structure is equipped with 10 in. thick walls (or
greater) and walkways that are 12 in. thick and 4
ft. or 5 ft. wide. The depth of the plant can be
over 20 ft. in total height. The walls are set on a
poured-in-place slab specially designed to receive
this type of wall. This plant is typically equipped
with Equalization, Aeration, Clarifiers,
Disinfection (chlorination and dechlorination or
ultraviolet disinfection), Post-Aeration and Sludge
Holding. The clarifying hoppers are typically 12
ft. square. Normally the walkways are finished with
toe plate and aluminum handrail on the inside of
the walkway and also on the outside if the plant is
more than 12 in. above the finished grade. The
structure is capable of being completely in ground
or primarily out of the ground with the base under
frost level.
We
can provide prints & specs for our
products
CUSTOM POST-TENSIONED
SBR'S:
Details
of Flat Wall Post-Tensioned
Tanks
(PDF)
Post-Tensioning
Defined, by the Post-Tensioning Institute
(PDF)
Dutchland, Inc. manufactures and
installs the structures which house the SBR
equipment, and installs a pre-engineered SBR
package by manufacturers such as Jet Tech or Aqua
Aerobics. Most of the time these SBR units are
placed within rectangular precast post-tensioned
tank structures which are equipped with common
walls (walls dividing two or more compartments).
The tank walls are 10 in. thick (or greater) and
equipped with a 4 or 5 foot wide walkway, which is
12 in. thick. The walls, which can be 20 feet or
higher in total height, are placed on a
poured-in-place base specially designed to receive
it. Generally Dutchland, Inc. recommends SBR
systems for installations over 300,000 GPD because
of price versus performance. However if the
engineer or owner prefers a smaller SBR, it is
certainly possible to build smaller systems. The
structure is capable of being completely in ground
or primarily out of the ground with the base under
frost level.
We
can provide prints & specs for our
products
CIRCULAR PRECAST
POST-TENSIONED WATER AND WASTEWATER STORAGE
TANKS:
Details
of Circular Post-Tensioned AWWA D115
tanks
(PDF)
Post-Tensioning
Defined, by the Post-Tensioning Institute
(PDF)
Click here to
view an open letter by
Jorgensen, Hendrickson and Close Engineers, Inc.
(an expert in the industry, involved with writing
AWWA standards) to engineers who specify AWWA D110
and/or AWWA D115 tanks.
Circular tanks manufactured by
Dutchland, Inc. meet specifications as described in
AWWA D115.
Water and wastewater storage
tanks with walls made of precast, post-tensioned,
concrete panels have been gaining popularity due to
the high quality control of precast concrete and
the long life span without maintenance. Dutchland,
Inc. has been manufacturing this type of tank since
1988, and to date has many tanks in operation.
These types of tanks typically utilize precast
concrete columns and a concrete roof or an aluminum
dome. The floors are generally cast in place
concrete. Vertical reinforcement typically consists
of Grade 60 deformed steel bars and/or
post-tensioned cables. All panels are cast
horizontally, hand-finished, and allowed to cure
before being shipped to the job site. After the
panels have been erected, the cables are inserted
through the conduits that are cast into the panel
walls. At this time, the cables are lightly
stressed and the joints between the wall panels are
grouted.
The advantages of precast
concrete walls include a high control of quality
throughout fabrication. The panel is cast
horizontally as opposed to a vertical,
poured-in-place wall, which means that the
reinforcing formations are set up in the mold and
spaced precisely as required. While the tank is
being fabricated, temperatures remain the same even
in adverse weather conditions.
The high maintenance costs
associated with steel tanks (dewatering,
sandblasting, repainting, refilling, etc.) is
avoided by utilizing a precast post-tensioned
concrete tank, which requires no interior or
exterior coating. In addition, the quality of the
concrete in a Dutchland, Inc. precast
post-tensioned tank does not require exterior
coatings to hide color differences or
irregularities in the wall panel concrete. The ribs
that are utilized in our radial tanks provide a
superior method of stability and reinforcing for
the overall precast post-tensioned radial tank.
These recently revised ribs extend 7 in. from the
outside wall of the tank and provide a structurally
sound and aesthetically pleasing finished product.
All radial wall panels are 8 in. thick and the
concrete is 5,000 PSI with type II cement. The tank
can be completely buried in the ground or it can
stand above grade with the base cast below frost
level.
Single basin systems are better
designed as radial tanks than as rectangular tanks,
simply due to the fact that radial tanks are a more
economical configuration and also provide the
structural advantages of a cylinder. However, it is
possible to manufacture a rectangular precast
post-tensioned tank for the use of water storage.
The rectangular tanks have been used primarily when
fabricating a wastewater treatment
plant.
We
can provide prints & specs for our
products
PUMP STATIONS & VALVE
VAULTS:
Since the early 1980's,
Dutchland, Inc. has been involved with producing
and constructing a large number of pump stations.
The typical pump station by Dutchland, Inc. is a
wet well and valve box arrangement; or in the case
of small pump stations, just a wet well. However, a
considerable portion of the pump stations in the
past have also been a wet well/dry well
combination, or wet well mounted (suction-lift)
versions. These versions are especially popular in
applications where large pumping capacities are
necessary. All precast pump station structures and
related concrete items manufactured with concrete
having a design compressive strength of 5,000 PSI
at 28 days, using Type II cement.
Since Dutchland, Inc. is a
precast company, we have the means to use a great
variety of tankage for pump stations, depending on
each individual application. Sizes range from 4
ft., 5 ft., 6 ft., and 8 ft. diameter manholes, to
large square and rectangular structures (e.g. 6 ft.
square, 8 ft. square). We are able to meet the
specific custom needs of the unusual situations, as
well as the typical.
We
can provide prints & specs for our
products
BOX CULVERTS, VAULTS, SEWER AND STORM WATER:
Dutchland, Inc. manufactures a large variety of sewer and storm water products. This includes items such as box culverts, vaults, retaining walls, manholes, inlet boxes, catch basins, septic tanks, oil water separators, grease and trash traps, etc. Dutchland, Inc. also manufactures a large variety of custom precast concrete structures. These structures are constructed in sections to allow them to be built to the sizes as specified. Dutchland, Inc. is capable of constructing a variety of load bearing structures from standard to H-25 load bearing (heavy highway loading). We also design and build retaining wall systems for storm water management, etc.
We
can provide prints & specs for our
products
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