AUTOMATIC REMOTE CONTROL DREDGING
Settled solids are excavated from the lagoon bottom by the LWT dredging unit which may be operated either remotely on shore and/or manually on board. The units forward and reverse travel, as well as its side to side lateral movements, are totally automated by a steel rail system located on the ends of the lagoon.

DISPLAY AND CONTROLS
With a lap top computer or desk top computer, the owner can observe a visual graphical image of the system's entire operations while working, and record operating data. 

Controlled by the PLC, the electronic control system directs the dredge to make "sweeps" covering the entire lagoon, automatically without an operator. The dredge is programmed to travel forward at a controlled speed, taking eight foot wide passes through the solids bed. When the dredge comes to the end of the run it automatically goes into high speed reverse, slows the pumping rate, and travels until it reaches the initial starting point for that pass. The dredge then raises the auger head, shifts laterally to the starting point of the next pass, lowers the auger head, restores the slurry pump speed and moves forward to continue dredging. Incorporation of LWT's BOTTOM SENSE™ will "float" the auger head and allow it to follow the bottom contour or stay a set depth off the bottom.

AUTOMATIC SOLIDS AND FLOW CONTROL
The solids/flow control system is also controlled by the PLC. The dredge travel function is electronically linked to the density meter providing an electronic signal proportional to the density of the slurry, to the PLC. The PLC control look compares the incoming signal to the adjustable solids set point and continuously regulates the solids delivered by the dredge. The same principle is used to regulate the flow volume. An electronic magnetic induction flow meter provides feedback to the PLC control look which, in turn, regulates the flow delivered from the dredge slurry pump.

The NEMA rated control panel for the Automated Rail Lateral Move System has displays and input controls for the speed and direction of the slurry pump, auger and the traverse system. An alpha-numeric readout displays slurry density, slurry flow rate, and shutdown fault messages. The display may optionally show the location of dredge in the pond, depth of operations, slurry pump pressure or other required functional feedback data. This system is compatible for a continuous process system or supplying material to a tank for batch feeding a dewatering system. For a batching application, level monitors may signal the dredge to run until the tank is full, then turn off until the low level sensor signal turns the dredge back on again.