Hydro International Hydro-Sludge Screen User manual

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.0-1
March 30, 2020
General Information
Hydro-Sludge™ Screen General Information
Overview
The Hydro-Sludge™ Screen is a horizontal in-line coarse material separator, comprising of four principle zones;
inlet, screening, pressing (compacting) and discharge. The feed from the inlet, enters the center of the screening
zone, where the coarse material retained on the inner surface of the perforated screen, is transported to the
pressing zone and onwards to the discharge by an Archimedean screw. Compacted coarse material (screenings)
is discharged into a suitable container, by the action of a regulated retention cone, controlled by a pneumatic
system linked the varying drive load (torque) of the drive motor.
Safety Precautions
The purpose of this Operation & Maintenance Manual is to ensure all personnel working with the plant are aware
of the safe and correct way to carry out any work. The instructions and information given are as explicit as is
reasonably practicable, however, competency and expertise are necessary in the operation and maintenance of
the machine, and to ensure reliable operation it is strongly recommended that such work is undertaken by only
experienced and authorized personnel.
Throughout this manual will be used to highlight important warning notes.
Before carrying out any inspection, maintenance, repairs, overhauls or commissioning on the Hydro-Sludge™
Screen; this manual must be read in detail, and always ensure that the machine has been isolated from both its
control panel and the raw material feed, where necessary to ensure that accidental starting of the machine cannot
occur.
In addition to the above, full adherence with current health and safety rules, acts, laws and legislation must be
observed, along with specific site procedures.
The Hydro-Sludge™ Screen must not be operated without operational protection devices and
covers in place.
The Hydro-Sludge™ Screen must not be used if any alterations have been carried out to the
machine which affect its normal operational behaviour, and more importantly any alterations which
affect the safe operation of the machine.
If any of the above are observed, isolate the machine and inform the person or department responsible for the
machine.
On completion of any maintenance, all guards/covers must be properly refitted before power and feed are
reinstated and the machine restarted.
This manual should be read in conjunction with the Electrical and Pneumatic Control Panel Operation &
Maintenance Manual, associated with the Hydro-Sludge™ Screen.
The Hydro-Sludge™ Screen warranty will be invalidated, and Hydro cannot be held responsible for product
failure, if:
The machine is used for work for which it was not designed or intended.

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March 30, 2020
The Hydro-Sludge™ Screen is used to process sludge outside the criterion detailed in the Technical Data,
see section 9.0, p17 ).
Damage is caused to the machine as a result of; operation and maintenance not being carried out to the
details of this manual, or operation without the required safety devices.
Any modifications or changes are carried out to the machine that affects its normal operation.
Known Hazards and Risks
The machine, when operated by fully trained personnel, is an exceptionally safe piece of equipment, which if
operated correctly and maintained as identified in this manual, should provide many years of service.
However, the following are areas that must be given due consideration at all times during the operation,
inspection and maintenance of the machine:
Moving Parts - These can become accessible when covers or guards are removed for inspection of the
operation of the machine.
Danger of cutting, shearing and crushing. Danger of contamination from the materials that have been
processed.
Pneumatic System - Compressed air must never be directed at uncovered skin, eyes, ears or any part of
the body.
Danger of grit/dirt being forced into the body under pressure of the compressed air.
Junction Boxes - Low voltage live terminals, will be accessible if the electrical supply is not isolated before
opening the covers.
Danger of electrocution.
Gearbox - Damage could be sustained to the gearbox housing if the breather or vent is not fitted, or is
blocked.
Danger of gearbox body bursting/cracking. Danger of contamination from oil spillage.
Central Joint - If the machine requires splitting in half for maintenance or inspection, then a small amount
of effluent could escape upon separation of the two halves.
Danger of contamination from materials being processed.
Avoid the above by:
Ensuring that only fully trained personnel operate, inspect and maintain the machine.
Ensure power and feeds are isolated.
Always wear appropriate personal protective equipment.
Wash your hands and any other parts of the body that come into contact with sludge as soon as
convenient.
Always observe all safety rules, acts and regulations when dealing with the machine.
The electrical devices fitted to the standard Hydro-Sludge™ Screen are not intrinsically safe, i.e.
they are not explosion proof, and therefore must not be installed in hazardous locations.

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.0-3
March 30, 2020
General Notes
Description of Operation
The machine is designed to process solid matter from fluids of higher viscosities i.e. sludge and comprises of four
main zones, as shown in Figure 3.a.
Figure 3.a: Functional Diagram
The main elements of the machine are the geared motor, integral screws, pre-determined perforated mesh
screens and retention cone, which regulates the discharge of the screenings.
There are two interfaced screws driven by an efficient geared motor arrangement, sized to accommodate the full
range of typical sludge’s expected, such that the full capacity of the motor is never exceeded. The first screw is
the screening zone, the other is the pressing zone.
As the feed is fed into the inlet of the machine, the screen starts to blind and the pressure inside the machine
increases. This pressure is detected by the inlet pressure transducer, which starts the machine, once the start
pressure set point is met (default - 0.1 bar). As the Archimedean type screening zone screw conveys the fluid,
particles larger than the chosen perforation of the mesh screen are retained. These are then conveyed by the
screw to the pressing zone. Free fluids passing through the mesh are discharged from the machine via a flanged
outlet connection fitted at the bottom of the machine in the screening zone body and progress onto the next
process.
The remaining material is compacted in the continual action of the pressing zone screw. The discharge of solid
matter is controlled by the retention cone situated at the end of the pressing zone. The retention cone initially
serves as a seal inside of the machine, until the screenings plug is formed. The retaining force of the cone is
continually adjusted by a relationship between the drive load of the motor and control pressure. As the plug
increases, the drive load increases and the corresponding control pressure (cone opening pressure) is increased,
balancing the cylinder pressure (cone closing pressure), allowing the screenings plug to push back the cone and
screenings to be discharged.
The discharged plug is gradually broken up against the retention cone, by the continual action of the cone
opening and closing against the nozzle. These pieces are then normally collected in a skip or enclosed bagging
Feed
Screened
Outlet
Screenings
Discharge
Screening Zone
Pressing Zone
Screenings
Outlet
Inlet
Inlet
Pressure
Transducer
Outlet
Pressure
Gauge
Moisture
Sensor
Center
Flange
Retention
Cone
Pneumatic
Cylinders
Screenings
Plug

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.0-4
March 30, 2020
unit, situated under the machine for final disposal. If a failure occurs and the plug in lost, resulting in a sludge
break-through, the moisture sensor inside the discharge box will detect this and immediately stop the machine,
and so long as the correct interlocks are in place, then the feed should also be stopped.
Once the pressure at the inlet drops below the set point, the machine continues to run for a preset run-on time
(default - 2 minutes) to clear the machine. If the pressure rises above the set point, the machine will run as normal
and the run-on timer is reset.
As a guide to the normal operation of the machine:
The drive load of the machine at idle (i.e. No load, feed or plug) should be 20-25%, depending on the
individual machine characteristics.
The optimal inlet pressure is 1 - 1.2 bar (14.7 - 17.4 psi) with trip point at 1.5 bar (21.8 psi), however the
machine will operate as long as a pressure greater that the start pressure set point is maintained.
The pressure differential between the inlet and outlet should be between 0 and 0.4 bar (0 to 5.8 psi).
A major benefit of this machine is that there is no requirement for washing or back flushing of the machine.
The degree of separation of solid matter is a condition of the selection of the screen perforation size (available in
2 - 10 mm), which also influences the quantity of screenings produced.
It is our experience with municipal sewerage sludge that an average of approximately ½ gallon of screenings is
produced per cubic yard of feed sludge.
With regard to the Hydro-Sludge™ Screen’s location in the process, Figure 3.b shows a typical arrangement. The
feed can either be pumped, fed by a tanker truck, or both. The addition of a reception tank can provide benefits in
balancing the flow to the machine, for both consistency and flow rate.
The requirement for the installation of a stone trap prior to the machine is dependent on the
specific site conditions. However, where fluid is likely to contain grit and/or stones, it is strongly
recommended.
The screened outlet is recommended as an open gravity discharge, however an elevated discharge of up to 3
yards is acceptable. However, the start pressure must be adjusted to overcome the back pressure.
Figure 3.b: Typical Hydro-Sludge™ Screen Process

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.0-5
March 30, 2020
Capacity of the Machine
The throughput of the machine depends upon many factors such as: -
The viscosity of the fluid being processed.
The flow rate at which the fluid is being fed to the machine.
The size, shape and quantity of the solid matter (screenings load) within the fluid to be processed.
The perforation size of the machine screens.
The condition of the machine (i.e. setting up and maintenance of the machine).
The capacity data is given in section 9.0 - Technical Data, and provides a guide to the possible throughputs.
Optimum Operating Conditions
The following are conditions that assist the Hydro-Sludge™ Screen to perform at its optimum, when treating
sludge:
Where the feed is pumped, we recommend that the pumps are selected from the centrifugal range, using
a non-clogging, vortex impeller.
Sludge should be limited to a maximum of 6% dry solids concentration.
Normal inlet operating pressure should be kept at between 1 and 1.2 Bar (14.5 – 17.4 psi).
Outlet pressure is variable depending upon feed pressure, sludge thickness, screen perforation size and
outlet pipework configuration, with typical pressure loss through the machine up to 0.5bar.
Where applicable, the machine should be protected against freezing conditions. This may involve heat
tracing and lagging.
The clearance between the screening zone screw and screen should be as small as possible, (almost
touching). (Note -This will have been set during factory testing before shipment or at commissioning)
Environmental Issues
At the end of the machine’s serviceable life, most of its components can be dismantled and recycled.
Always ensure that current laws, regulations, legislation and directives for disposal are adhered to.
When dismantling the machine for disposal, take care to identify the materials correctly.
Table 3.a provides a guide to the key components materials of a standard machine.

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.0-6
March 30, 2020
Table 3.a: Hydro-Sludge™ Screen Materials
Material Parts
Stainless Steel
Screening Zone and Pressing Zone Screens
Pressing Zone Screw, except for keyed stub shaft
Inspection lid hinges on the screenings discharge cover
Adjusters and lock nuts for the wheels on the Pressing Zone body
Pressure Transducer adapters
Clutch Rod
Turning piece
Discharge chute
Intermediate ring
Gearbox Collar
All nuts, bolts and washers
Mild steel
Screening Zone and Pressing Zone bodies and supports
Screening Zone Screw flights and main shaft
Pressing Zone Screw keyed stub shaft
Screening discharge cover
Inlet box access opening covers
Inlet box access plate
Screw shaft covers, either end of the machine
Intermediate Flange
Cast iron
Inlet and Discharge boxes
Nozzle inside Discharge box
Bearing Housing and cover
Gearbox housing
Aluminium
Pneumatic cylinder casings
Pneumatic cylinder adaptors
Motor body
Cladding for the trace heating & lagging
Bronze / Brass
Stuffing box follower
Thrust shim
Cutting Ring
Lubrication ring
Lock Nuts on Pressing Zone Screw
Plastics / Rubbers
Screening discharge inspection cover handle
Retention cone
Roller wheels
Pneumatic air lines and coils
O-Rings and gaskets
Oil Gearbox, Cyclo and Helical sections
Other grease / lubricants Grease pipes to retention cone and gland packing seal.

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.1-1
March 30, 2020
Section 1
Installation / Removal of the Hydro-Sludge™ Screen
Installation
Following delivery, after careful removal of any packaging materials, the machine should be checked for damage
and prior to installation, Hydro International must be notified immediately if any damage is found.
To install a machine for the first time or following repair, the following instructions must be followed:
•Lift the machine into position using appropriate and certified lifting equipment, such as a crane, ensuring
that the machine is lifted using its lifting lugs. See Figure 4.a.
Lifting from any other position, or the use of straps around the body, could result in damage being
caused to the machine and / or risk of injury to personnel. If the machine is heat traced and lagged,
care should be taken not to dent or damage it.
•Once in position, ensure that the machine is upright and level. Bolt the screening zone section of the
machine to its supporting medium, i.e. steel platform or concrete slab, via the two fabricated supporting
brackets.
•Adjust the four wheeled support legs to align the longitudinal axis of the screening and pressing zones
using the nuts on the spindles.
•Connect a drain hose, if required, to the 2” hose tail located on the underside of the inlet casting.
•Connect feed and discharge pipework to inlet and outlet flanged connections on the machine.
•If applicable, install any screenings discharge chute, ensuring that a gap is left between the machine chute
fixed to the underside of the discharge box and the main discharge chute, to allow the machine to be easily
split for maintenance.
•Position the screenings collection system below the discharge chute.
•Carryout the required electrical cabling and connections to the machine device (i.e. motor, pressure
transducer, moisture sensor, discharge cover switch and trace heating) where fitted.
•Connect the pneumatic air supply pipes to the ports of the coils from the pneumatic cylinders.
•Once the installation is complete and prior to the commissioning, ensure that the Hydro-Sludge™ Screen is
protected from freezing conditions.
Removal
If a machine must be removed for repair, the following instructions must be followed:
•Isolate and lock off all feeds and power supplies.
•Disconnect all cables, pipework and pneumatics.
•Unbolt the screening zone section of the machine from its supporting medium (i.e. steel platform or
concrete slab) at the two fabricated supporting brackets.
•Lift the machine from its position using appropriate and certified lifting equipment, ensuring that the
machine is lifted using its lifting lugs. See Figure 4.a.
Lifting from any other position, or the use of straps around the body, could result in damage being
caused to the machine and / or risk of injury to personnel. If the machine is heat traced and lagged,
care should be taken not to dent or damage it.

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.1-2
March 30, 2020
ALWAYS USE THE MACHINE LIFTING LUGS TO LIFT THE MACHINE.
Figure 4.c: Lifting Arrangement
ALWAYS ENSURE THAT THE HYDRO-SLUDGE™ SCREEN IS BALANCED WHEN LIFTING.
30° - 90°
Note! The angle between the lifting chains
/ straps should be between 30° & 90°.
It is important that when larger angles are
used that the chains / straps have been
correctly tested before use.

© 2018 Hydro International O&M Manual Hydro-Sludge™ Screen •Page 2.2-1
March 30, 2020
Section 2
Hydro-Sludge™ Screen Start-Up
Where commissioning is not part of the scope of supply for the machine or where the equipment has been re-
installed, the following instructions must be followed:
Before starting any commissioning, check that the machine and panel have been correctly installed
and securely fixed into place.
The site commissioning should be broken down into dry and wet commissioning.
Dry Commissioning
Checks to be carried out before electrical power is applied
•Check all the Hydro-Sludge™ Screen and control panel wiring and air line connections are made.
•Check the Hydro-Sludge™ Screen rollers are set and tight, adjust as necessary.
•If the inlet box has a gland packing seal, check that a drain is connected to the hose tail on the underside of
the inlet box.
•Ensure that the inlet and outlet pipework is securely connected.
•Check that there is some sort of container below the discharge chute to collect screenings.
•Open the breather on the outlet pressure gauge.
•Check the power feed certificate for the supply.
Checks to be carried out following electrical power switch on to control panel
Do not allow the machine to run for longer than 5 minutes during dry testing.
•Check the power supply into the control panel.
•Switch on the panel isolator, check for successful boot up and select manual mode.
•Check that the compressor starts and charges the reservoir for to a cylinder pressure of about 3.5 bar (50
psi).
•Start machine in manual using the start button and check rotation of the motor in relation to directional
arrow on shaft cover. (Clockwise at the gearbox end)
•Check drive load is approx. 20-25%.
•Ensure that the machine stops in manual mode via the stop button and then restarts again.
•Operate the emergency stop switch on the panel. Check that the machine stops. Release the emergency
stop, reset the panel and start the machine.
•Operate the emergency stop switch adjacent to the machine (if applicable). Check that the machine stops.
Release the emergency stop, reset the panel, and start the machine.
•Open the screenings discharge hatch. Check that the machine stops. Close the screenings discharge
hatch, reset the panel, and start the machine.
•Switch the moisture probe override on. Using a wet cloth, wipe the moisture probe. The machine should
continue to run. Dry the moisture probe, reset the panel and start the machine.
•Switch the moisture probe override off. Using a wet cloth, wipe the moisture probe. Check to ensure that
the machine stops. Dry the moisture probe, reset the panel, and start the machine.
•Check the span of control air to ensure that the control and cylinder pressures are equal at maximum drive
load (default 80%).

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Wet Commissioning
•Set the machine to auto and start the sludge feed. Note - It is advantageous to have reasonably thick
sludge for commissioning as this helps produce a plug quickly.
•Check that the panel is monitoring pressure and the machine starts at set point (default 0.1 bar or 1.5 psi).
•Once the machine is full of sludge, stop the feed, recheck the drive load (approx. 20-25%) in manual and
adjust as necessary. Record drive load and amperage.
•Measure and record the position of the screw, dimensions Ls& Lp. Dimension sum should be same as
result for Factory Test.
•Restart the system. It is likely that some sludge will spray into the discharge box, as the plug is forming,
which may trip the machine. If this happens, the moisture detector should be switched to override during
the start-up operation and the panel reset. Once returned to normal operational mode, the moisture
detector override can be switched off.
•Make a record of the pressure values at both the inlet transducer and outlet gauge. The pressure
differential should be between 0-0.4 Bar (0-5.8 psi).
•Make a record of the drive load and amperage with sludge.
Note -Once the plug is formed, screenings will start to discharge. Initially they may be wet but will dry
with time, which could be up to several hours depending upon the type and condition of the sludge.
•
•If Gland Packing: Tighten stuffing box follower, until there is only a slight drip from the seal.
•If Mechanical Seal: Check that the mechanical seal has a good seal with no leaks.
•Stop the sludge feed and check that the inlet pressure drops below the set point and that the machine runs
on for the preset time (default 2 mins). If the pressure does not drop below the set point, check the outlet
pipework for static head and adjust to compensate. If the start pressure is adjusted, record the new setting.
•Start the sludge feed again and check that the machine starts, particularly if the set point was adjusted.
•If possible, induce an inlet pressure of over 1.5 bar and check that the machine trips. Then reset the panel.
Note - If there is no interlock between the machine and sludge feed, there is a risk of blowing out the plug.
•Continue running sludge through the machine to check the general operation.
•Carry out and record any necessary fine adjustments of the pneumatic panel (i.e. cylinder pressure, control
pressure span etc.).
Data Collection
The following is important data that should be recorded and entered onto the record data sheet, which can be
found in the appendix, section 11.2.2:
•Position of screw. (Ls/ Lp)
•Drive load and Amperage at idle. (No load, feed or plug)
•Pressure values and differential during processing
•Drive load and Amperage during processing. (Under Load, with feed and plug)
•Approximate sludge throughput in yd3/hr
This data will be the datum settings, which will eventually change during the machine’s working life.
It is therefore important to take further readings, recording them on the record data sheet, as this will indicate the
performance and condition of the machine, and whether any maintenance is required.
It would also be useful to record the following data to indicate performance of the machine.
•% dry solids of the sludge. (This will have to be laboratory measured from samples taken.)
•% dry solids of the screenings. (This will have to be laboratory measured from samples taken.)