A "Green" Company Since 1990

Batch pH Neutralization Systems

The HydroFlo Batch pH neutralization systems are designed to neutralize the pH of highly acidic and highly alkaline process or waste streams to a specific set point. They are designed to process anywhere from 50 to 10,000 gallons per batch.

HydroFlo systems are completely automated, requiring no operator attention other than periodic system maintenance. Remote monitoring via SCADA, building management, or dial-up link available.

Every HydroFlo system is robust in design and construction and is built to work continuously, problem free, day in and day out. Everything needed is included: pumps, mixers, controls, etc. Sophisticated controls continuously monitor pH levels and seamlessly adjust pump outputs, assuring that your effluent meets the desired levels.

Application

Batch treatment systems are typically simple in concept and yet, (depending on application), complex in execution.

HydroFlo's pH neutralization systems are very versatile in that they can process large batches quickly, when the influent chemistry is close to the treatment set point, and can also handle highly acidic (Acid Neutralization) and highly alkaline (Caustic Neutralization) process or waste (Waste Neutralization) streams and accidental spills. This system is normally used in applications that see widely varying flows and widely varying influent chemistries.

Standard Features:

  • Skid mounted

  • Stand alone operation
  • Compact design for small footprint
  • Epoxy coated ASTM A-36 carbon steel skid
  • Factory tested
  • Pre-piped
  • Pre-wired
  • Seamlessly integrates with other HydroFlo offered wastewater products
  • State of the art NEMA-4X, UL 508 electrical enclosure
  • Standard units can be manufactured to treat batches from 50 to 10,000 gallons
  • TEFC motors

Available Options:

  • Access platforms with ladder or stairs

  • Available in epoxy coated carbon steel, stainless steel, polypropylene, FRP, exotic alloys and all thermoplastics for long life and superior corrosion resistance
  • Duplex systems for redundancy
  • Effluent monitoring
  • Effluent sampling
  • Explosion-proof design
  • Influent equalization
  • Influent / effluent lift stations
  • On board reagent storage (day tanks)
  • Potable water design
  • SCADA system monitoring
Equipment Design Data & Sizing Calculations

Chemical Pump Dosing
  Rates

Chemical Compatibility
  Charts

Application Questionnaire

Drawings
 

General Arrangement
  Drawing

Standard Process and
  Instrumentation Diagram

Specifications
 

Batch pH Neutralization
  System
  Engineering
 
Specification

"Common" Engineering
  Specification
  Applicable to all HydroFlo
  Manufactured Equipment

Installation, Operation & Maintenance Manuals

Standard IO&M Manual

General IO&M
  Considerations
  Applicable to all HydroFlo
  Manufactured Equipment

Process Description

HydroFlo batch pH neutralization systems are designed to accept batches ranging in volume from 50 to 10,000 gallons. In order to allow for fluctuating flow rates and system surges, a primary equalization tank (or main collection sump) is required. A level control (typically an ultrasonic or continuous output bubbler level sensor) is used in the equalization tank and the treatment tank. A Programmable Logic Controller (PLC) within the Main Control Panel (MCP) monitors the tank levels. When the level rises above the 10% full mark, a recirculation / transfer pump is started. If the treatment tank is empty, the equalization system automatically transfers a batch (if it is available) to the treatment tank. Once the treatment tank fills to the high level, the transfer from the equalization tank stops and the equalization tank reverts back to the recirculation mode. The treatment tank then treats the tank contents using "Continuously Variable Batch Treatment" technology, developed by HydroFlo. Once the reaction tank contents reach the pH set point, the contents can be transferred to the process stream or directly to sanitary sewer. When the treatment tank descends to the 10% full level, transfer from the first stage equalization resumes and the process repeats.

NOTE:
A pretreatment option is available for the equalization tank. This option allows for coarse treatment of the equalization tank contents.

The Equipment:

The basic system is comprised of a skid, reaction tank, reagent storage tanks, valves, plumbing, a mixer, chemical metering pumps, and a control panel.

Skid:

A steel skid is provided for supporting the entire system. The skid  features a welded 4" steel "C" channel frame, and a 1/4" steel deck plate. The entire skid is blasted to an SSPC-SP6, and coated with a 2 part self priming epoxy finish for corrosion resistance. The skid color is OSHA Safety Blue, unless otherwise specified.

Optional Containment Pan: As an option, a containment / drip pan can be provided for protecting the steel skid from leaking or spilled corrosive fluids. A drain connection is provided for plumbing the containment pan to a suitable location. The pan can be fabricated from polypropylene, stainless steel, etc. and features 8" high walls.

Reaction Tank:

There are many items to consider when choosing the reaction tank.  What are your batch sizes expected to be?  How much do you generate daily?  What is your peak flow?  What chemical processes are going to be applied?  Will the reaction be exothermic (create heat)?   If so, how much heat will be generated?

HydroFlo addresses all of these items, as well as others, in order to properly size the system and choose the correct materials of construction for the application.

Typical Poly Reaction Tank: The reaction tank is manufactured of HDPE polypropylene.  The tank is designed for fluids with a s.g. of up to 1.9 with a safety factor of 2:1. Destructive burst testing has shown that tanks of this construction often have an ultimate load safety factor exceeding 3:1. If positive ventilation is used the tank is rated to +/- 20" w.c. The top will support all mounted equipment and the weight of one 200 lb. man without significant deflection.

NOTE: The system detailed here is fabricated from polypropylene.  Polypropylene is typically used for long service life and superior corrosion resistance.  As an option, we can fabricate the system from any commercially available material including epoxy coated carbon steel, stainless steel, FRP, exotic alloys and all thermoplastics.

Reagent Storage Tanks:

Chemicals for treatment are pumped directly from 55 gallon DOT drums.  An alternate to pumping directly from DOT drums is utilization of day tanks, which can be automatically refilled from the customer's bulk chemical delivery system within the plant. Redundant level sensors and redundant fill valves provide protection against overfilling.

Valves:

All ball valves are true union, field serviceable valves. All diaphragm valves are flange mounted. Elastomers are EPDM and Teflon, except on concentrated acid lines where the elastomers are Viton and / or Teflon.

Plumbing:

All recirculation, transfer and discharge lines are fabricated from solvent welded, PVC SCH 80 pipe. All reagent delivery lines are flexible PFA tube, double contained within a clear  flexible PVC hose, clamped at each end to seal leaks.

Mixer:

The mixer is one of the key elements of the system.  The system will not generate consistent results without a properly sized mixer.  Typically, mixers are sized to turn over the tank contents at a rate not less than 2 times per minute.

Chemical Metering Pumps:

Properly sizing the chemical metering pumps is important in order to achieve the correct chemical reactions.  Also, metering pump sizing has an impact on total chemical consumption.  Properly sized pumps will help you reduce overall chemical costs.

Control Package:

All HydroFlo batch treatment systems are fully automated.  Control packages (depending on your specific requirements) are available in either basic relay logic controls or a full state of the art PLC with touch screen HMI and our sophisticated treatment algorithms. The relay logic controls package allows basic reconfiguration of the original system settings, while the PLC based package allows maximum flexibility to change the process parameters, as well as tight control that minimizes chemical usage. We can include a variety of options including digital data logging of critical process parameters, Ethernet access to process data, communication with Building Management Systems, and even remote system access using cellular wireless technology.

All enclosures are NEMA 4X. Where metallic enclosures are used, they are provided with epoxy or polyester finishes for corrosion resistance. All conduit is plastic coated, where possible. Low voltage 24VDC is used throughout to minimize service personnel exposure to high voltage. All panels are OSHA LOTO and NFPA 79 compliant.  UL-508 listing is available.

Effluent Monitoring: As mandated by the local controlling authority, the effluent quality must be continuously monitored. A two pen recorder is to be used to monitor effluent flow rate and pH. The recorder is to be equipped with a flow totalizer. Any effluent pH deviations will trigger an alarm and system discharge will be halted.

System Packaging:

The system is supplied as a completely fabricated "turnkey" package. All devices are pre-wired and plumbed.

You need to make the plumbing connections to and from the system and a single electrical connection point for incoming power.  The disconnect on the MCP provides OSHA Lock Out / Tag Out and NFPA 79 compliance. Systems requiring compressed air, also require only one connection  and the valve is supplied for OSHA LOTO.

Additional Information

For specific equipment information, contact us directly. We can provide the specifying engineer with a formatted specification package that thoroughly describes any of our systems for bidding purposes. This includes detailed drawings, and detailed equipment specifications.