The HydroDoc™ is the most efficient and best operating rotary distributor available anywhere. Trickling Filters can be a reliable part of the efficient operations of wastewater treatment plants. The HydoDoc™ is completely hydraulically driven, just like our Standard Rotary Distributor. The HydroDoc™ has automatically adjusting gates which are pneumatically controlled to open and close the orifices in equal proportion on both sides of the distributor arms. A sensor on the center assembly transmits speed readings to the control box, which automatically adjusts the speed to match the preset operational or flushing program. As flow to the trickling filter varies, the speed is maintained by automatically adjusting the gates over the orifices.
By regulating the dosing through the filter media, the biomass becomes healthy throughout the depth of the trickling filter. A daily flushing cycle cleans the media and flushes dead biomass, leaving an optimally active film on the media. Healthy media results in optimal treatment process.

Over nearly forty years of process engineering experience WesTech’s focus on process optimization has included improvement of trickling filter performance. The Achilles’ heel of traditional rotary distributors has been that the dosing rate of the flow to the  trickling filter has been at the mercy of the hydraulic flow.

Controlling the speed of a rotary distributor and in turn controlling the performance of a trickling filter was first practiced in 1983. WesTech has successfully provided hundreds of distributors that offer these process advantages. The HydroDoc™, makes this process even easier to operate and maintain. Controlling the dosing rate of the trickling filter is the key advantage of the HydroDoc™.  The HydroDoc™ turns the tremendous momentum and torque contained in the rotary arms into a mechanical and operational advantage. No longer is there a need to add energy or speed control using a center drive unit. The HydroDoc™ simply uses the hydraulic energy already present in the trickling filter to control the speed of the distributor.

In new installations, and retrofit projects, HydroDoc is winning over plant owners and operators.  According to Reed Fisher, Plant Manager at Central Valley Water Improvement District in Salt Lake City, Utah; “HydroDoc is a cleaner way to properly run a rotary distributor with a lot less maintenance.  WesTech came up with a better Rotary Distributor, the maintenance is wonderful!”

ADVANTAGES
 No Gears-No Sprockets-No Chains: There are no associated mechanical drive problems or maintenance. No chance of drive damage from ice build up or wind, and no chance of oil spills.  

Hydraulically Driven: No electric drive means energy savings. Only power consumption is by PLC Panel, and air compressor. No electricity is used to turn the distributor. 

Optimal Speed: The HydroDoc™ maintains an optimal distributor speed. A speed sensor monitors the actual speed of the distributor arm and the PLC adjusts the gates to produce the optimal preset speed even when the flow changes.  Proper operation does not depend on establishing or maintaining neutral thrust on the arms.

Never Off Line: If the control system fails, power is lost, or compressed air becomes unavailable, the distributor will continue to rotate at a default preset speed, until the system is back on line. Then, the controller will automatically resume programmed rotational speed.

Less Maintenance TIme: HydroDoc™ is equipped with an E-stop pushbutton that will automatically bring the arms to an immediate stop without turning off the flow to the rotary distributor. This feature benefits the safety and maintenance efforts of the operators. Without the hassle of shutting down and ramping up pumps or shutting off water. Maintenance personnel can get to the center assembly quickly and safely to conduct any normal maintenance tasks.

Spreaders Stay Clean: The spreader ports covered by the gates are not apt to become blocked because the valve gates wipe the ports periodically to clear obstructions that might exist. If orifices do plug, the controls will automatically compensate for the imbalance and keep the arms rotating at programmed optimal speed.

Easy Retrofit: Upgrading existing Distributors to the performance advantages of the HydroDoc is can be done quickly, and with minimal disruption to plant operations. 

PROVEN PROCESS BENEFITS
• Improved oxygenation
• Improved nitrification
• Higher BOD reduction
• Extended media life and service
• Odor reduction/elimination
• Significant snail and filter fly reduction

WesTech  provides continuing process evaluation during and after installation and start up of HyrdroDoc units. This service includes recommendation and evaluation of initial trickling filter setup and proper SK rates to achieve optimal performance. Annual evaluation of the trickling filter performance for up to five years is also provided to assure ongoing process efficiency. 

Manufacturing and operating the HydroDoc™ Rotary Distributor is covered by US Patents 6,231,756 / 5.096,588 and 5,660,435 and United Kingdom No. GB23579861