The Modulair wastewater treatment plant is one of the most reliable, maintenance- free methods of wastewater treatment available for residential, commercial or small municipal applications. With system capacities ranging from 5000 to 500,000 gallons per day, Modulair plants are pre-engineered to accommodate current, as well as, future treatment needs. Modulair plants employ the extended aeration process to quickly and efficiently oxidize organic compounds in the most cost-effective manner.
Some Features
 | The Modulair is a low profile installation and aesthetically pleasing |
| The plant design is flexible and trains can be added as needed - perfect for subdivisions built out over a few years |
| The plant design capacity can be engineered by SES |
| The concrete trains are easy to install |
| It is easy to operate |
| A small building houses a laboratory for effluent testing |
| The system has no detectable odor |
| Rapid sand filters can be added if required by permitting agency |
| The Modulair is constructed of 5,000 psi reinforced concrete. |
The tanks are constructed in segments and delivered to the project site ready for installation.
Process Description
The Modulair utilizes the extended aeration method of wastewater treatment to achieve the level of treatment required for each specific installation. The system is designed to meet or exceed the requirements of TEN STATE STANDARDS which govern plant design in the ten major states in the northeast United States.
Basic Design Criteria:
| AERATION |
| Criteria | 10 State Standard | Modulair |
| Organic Loading | 15 lbs. BOD/day/1,000 cf | 12.5 lbs. BOD/day/1,000 cf |
| F/M ratio lb BOD/day per lb ML VSS | 0.05-.1 | 0.0572 |
| MLSS (mg.l) | 3,000-5,000 | 3,000-5,000 |
| Liquid depth | >10' and <30' | 7.6' - 13' |
| Tank volume | 2 or more tanks | Min 3 tanks/train |
| Min DO level | >2.0mg/l 1.8 lb. 0 lb. peak BOD | >2.0mg/l 13.2 lb. 0 lb. peak BOD |
| Oxygen transfer | 2,000 cf/lb. BOD | 2,000 cf/lb. BOD |
| Blower units | Stand-by required | 100% stand-by |
| Diffusers | 200% design average. Removable with 4 tanks or less | 200% design average. All removable |
| Piping head loss | <0.5 psi at diffuser inlet | <0.5 |
Details on How the Modulair System Works
Aerated Flow EqualizationFlow equalization in the range of 50% of the average daily flow is provided to allow for the normal fluctuation of wastewater flow during the daily 24-hour period. Sewage discharging into the equalization tank(s) are aerated to start the biological process and to minimize the possibility of odors developing. Under normal circumstances the wastewater is conditioned by a comminutor and metered prior to the equalization tank(s).
The stored and aerated wastewater is conveyed at a steady rate to the aeration tank(s) using duplex submersible pumps which are activated and controlled by floating switches. The pumps deliver the wastewater into a weir box near the top of the last equalization tank and two adjustable weirs are used to meter the flow (at the rate of the hydraulic or biological capacity of the given system) into the treatment process. The duplex pumps alternate or are manually switchable, depending on design requirements and are driven by motors generally under one horse power therefore power consumption is low.
Aerated Wastewater Treatment (Aeration)
The volume of the aeration tank(s) is determined by setting the residence time, usually 24 hours. Wastewater is introduced into the first aeration tank by the transfer pumps from the last equalization tank and then flows through the aeration tank(s) in a serpentine manner to eliminate short-cutting or dead zones.
Aeration is achieved through the use of diffusers which are located at the ends of the tanks, approximately one foot from the bottom. Coarse air bubbles roll and mix the sewage to maintain the desired dissolved oxygen levels (1.5 to 3.0 mg/l) and the air delivery system is adjustable for quantity and pressure. The diffusers are easily removable for inspection and cleaning. There are no mechanical components in the aeration tank(s).
Settling or Clarification
Settling tank(s) also utilize the standard tank configuration but hoppers are installed to facilitate the settling of solids and their removal or recirculation. Each tank is equipped with two airlift systems: one for the removal or recirculation of the settled sludge and the other for the removal of solids floating on the surface.
The clarified liquid is discharged from the tank(s) through the effluent weir and discharge system where a submerged pump sprays liquid in the aeration tank to control foam when/if required.
| CLARIFICATION |
| Criteria | 10 State Standard | Modulair |
| Hydraulic Loading | 200-400 gpd/lf per flow | varies <400 gpd/lf per flow |
| Solids loading | 1-23 lbs/sf avg | <50 lbs/day/sf |
| Inlet design | Baffles | Baffles |
| Weirs | 1,451 gpd/lf | <1,451 gpd/lf |
Modulair treatment plants provide a minimum of 85% reduction in BOD and SS but can be configured to provide a higher level of treatment if required, including denitrification.
Aerated Sludge Holding
Usually located between the equalization and aeration tanks, the sludge holding tank(s) are also aerated to prolong the biological process and to prevent septic conditions from developing. When ready for sludge removal the air supply is shut off and the sludge settles. An airlift system removes the sludge from the bottom using fixed suction piping. In general, the settled sludge will contain 3% - 4% solids and the sludge holding tank volumes are selected to extended period of time between sludge removals.
Air Delivery System
The air delivery system comprises compressors, including stand-by unit(s), galvanized steel piping of various diameter, valves, pressure controls and diffusers. Compressed air is used for aeration and sludge transfer.
Capacities
The Modulair wastewater treatment system can be configured to virtually any capacity or effluent requirement. For projects below 10,000 gallons/day the use of large capacity Singulairs can be more cost effective. The Modulair system can be designed to handle up to 500,000 gallons/day.
Siegmund Environmental designs and installs the Modulair both locally and in overseas markets. For project examples, see the photographs.
Contact us to learn about our design, build and operate program and to find out how we can provide a clear solution for all your wastewater needs.
