Spotlight on trashrakes13 February 2012
IWP&DC presents details on some of the latest trash rake systems available on the market
Various types of trash can accumulate in front of hydro power and waste water intakes, swimming on the surface or submerged on the ground in front of the intake. A high quality trash rake cleaning system avoids operation disturbances and even shutting down of a generator unit.
To achieve a maximum water throughput rate for energy production at a facility it’s important to choose the right technology so as not to lose efficiency. Consideration has to be given to the site location, the local types of debris and customer requirements. Each project and situation is unique and requirements are different. The debris can consist of branches, logs, leaves, grass, plastic, sedimentation, rocks or milfoil grass.
Kuenz (www.kuenz.com) has delivered more than 130 high performance trash rake cleaning installations to customers all over the world. The components of the Kuenz trash rake cleaning machines are standardised. The machine is built on a modular concept, allowing the fulfillment of specific site and customer requirements. Flexibility, robustness and multifunctional designs are all key features.
Depending on the customers’ requirements, Kuenz offers hydraulic operated or rope type machines which work in manual, semi-automatic or fully-automatic mode. A unique machine design allows the operator to complete additional tasks such as sediment removal and the lifting and lowering of stop logs and screens.
Hydraulic trash rake cleaning machines are recommended for: Bulky and oversized debris; Trash carpet on the water surface.; cleaning depth of 7-32m; removal of sediment or large rocks from the bottom of the intake; and vertical or inclined trash racks.
Rope trash rake cleaning machines are recommended for: narrow space conditions on the dam; deep intakes up to 100m; circumstances when existing civil structures demand a rope type machine.
Optional equipment, discharge and removal systems include: stop log lifting devices on the upper or under water side; hydraulic jib crane with rotator and gripper; tilting flaps; moveable chute; telescopic chute; attached roll-off container or roll-off container mounted on a separate wagon; channel systems.
Hydro Component Systems (www.hydrocomponentsystems.com) offers patented electro-mechanical (no hydraulics) trash rakers designed to remove captured debris from a wide variety of new or existing water intakes. Tested under full-rated load conditions prior to shipment, HCS trash
rakers have been designed to perform efficiently even under extrem weather conditions – they can operate in hurricane winds of up to 150 mph. According to the company, advantages of the system are: quick cycle time; no hydraulics, therefore no hoses, reservoirs or exposed cables; simple operation; high-load capacity; and they are designed to be easy to maintain
The company offers different rakers for unique needs, including a range of manual or fully-automatic trash rakers that can be customized to meet the specific needs of a facility. All trash
rakers offer two control options: handheld radio-controlled pendant t water intake, or fully-automated system that can be activated locally at the intake or from a remote location.
The Standard Manual Trash Raker travels in a straight line, offering simple operation with high-load capacity, while Dual Rakers collect twice as much debris in half the time at large intakes (over 100ft wide). If one raker is disabled, the second raker will automatically take over the cleaning of the entire rack.
Other options are an Articulating Raker, which navigates on a track to handle curves, allowing for job site customization, and a Pivot Raker, which turns 360 degrees on a turntable bearing and features a cam-actuated boom, making it ideal for tight-space applications.
Ashland Hydro Trash Rakes (www.hydrotrashrakes.com) offer a knuckle-style boom device designed to reach into the depths of the water – up to 50 ft – and engage the bottom of the trash rack bars. An articulating rake (with an opposing thumb attachment) at the end of the boom sweeps the rack bars of any debris on its upward stroke. The Trash Rake system can move the length of the intake, by a 2 or 4wd trolley system that runs on two 80# rails mounted onto your deck. This allows the operator to easily move the machine along the intake to handle debris or perform simple facility maintenance, says the company.
Ashland Hydro Trash Rakes, formerly known as Hawk Trash Rakes, are designed to remove a wide variety of debris from weeds to logs as well as man-made debris. The rake head is equipped with an opposing thumb allowing objects up to 25” in diameter to be handled. Ashland Hydro Trash Rakes features two models: the TR3500 model works up to a depth of 35 feet, and the TR5000 model works between depths of 35 to 50 feet.
Both models are rated to lift 4,000 pounds at the rack and 1,000 pounds with the arm extended 15 feet out from the rack. For purposes of determining debris disposal options, the machine can lift approximately 1,000 pounds to a height of about 26 feet above the deck.