Introduction to Wastewater Treatment Mark O. Liner, P.E. Naturally Wallace Consulting

Wastewater Engineering If I gave you a jar of this and said ….get it clean. What would you do?

How to go from A to B to C? Treatment of Natural Gas Condensate

Reverse Engineering Glass of water and add: Sand Sugar Salt Oil How do you make this water clean?

Design Steps Decision: Wastewater Treatment is Needed Basis of Design Process Selection Preliminary Design Final Design

First Step: Basis of Design Most important step of the project !!! Foundation for all decisions Dictates project $$$s Changing the Basis of Design halfway thru the project is like changing ….

Basis of Design Data Flow Influent Characterization Effluent Requirements Miscellaneous Considerations

Flow – Measurement Weirs Flumes Meters Beware of chunks

Flow - Domestic Usually predictable

Flow - Industrial Usually unpredictable Engineers want predictable

Flow - Equalization Hold and discharge Treat as it comes Treatment Equalization best money spent Gets you to steady state Treatment Equalization Treat as it comes Equalization Treatment

Flow – Design Numbers Minimum and maximum hourly flow For pipe/channel sizing Average daily flow For mass balance, chemical usage, and sludge production

Characterization - Analytes Nitrogen Phosphorus pH Alkalinity Metals Bacteria/Algae Solids Total (TS) Dissolved (TDS) Suspended (TSS) Organics Biodegradable (BOD) Chemically Oxidized (COD) Volatile (VOC) Oils (O&G, TPH)

Characterization - Table Average plus one standard deviattion

Effluent Requirements Typically set by government Depends on disposal method River Groundwater Land Moving target ??? It pays to discuss and negotiate

Miscellaneous Site Constraints Climate Money Time Land Availability Capital Costs Operating Costs Time Start date Project Life

Design Steps Decision: Wastewater Treatment is Needed Basis of Design Process Selection Preliminary Design Final Design

Second Step: Process Selection Given a Basis of Design, what is the best way to go from A to B to C??? Experience is crucial in this step Engineer/Vendor dance

Process Selection

Process Selection Proof of Concept Coffin Butte Landfill, Oregon Pumped flow from leachate barrel, Masterflex peristaltic Standpipe, unglued grease slip fit to elbow Collection header same as underdrain Distribution header same as underdrain Inexpensive poly tank 44-gal, AES BT44 Recirc Inexpensive poly tank 44-gal, AES BT44 bh Masterflex peristaltic Tank 1 bh Tank 2 tu tu Tank 3 To drain tu bh Tank 4 bh tu tu tu tu tu bh bh tu tu bh Blocks tu tu tu tu BOD Removal - passive Nitrification / Anammox – FBA (aerated) Nitrification / Anammox - FBA (aerated) Graduated poly tank 55-gal with lid, AES T55 Denitrification / metals removal

Process Selection – Pilot Plant

Process Selection – Primary Treatment The lowly septic tank – the “greenest” wastewater treatment technology No electricity…

System Selection – Primary Treatment Solids removal Screening Grit Removal Sedimentation Floatation Dissolved Air Floatation Oil/Water Separator Removing sand

System Selection – Biological Treatment Soluble wastewater can not be removed as a solid So, we have bacteria eat it and remove them The trick is to create an environment for them to live and STAY

System Selection – Secondary Treatment

System Selection – Biological Treatment Design Considerations Aerobic and anaerobic bacteria Periodic sludge removal Solids separation to keep bacteria from flowing downstream Nutrient requirements (industrial Limits 30 mg/L Biochemical Oxygen Demand 30 mg/L Total Suspended Solids

System Selection – Tertiary Treatment Filtration Membrane Sand Carbon Chemical Addition pH Adjustment Disinfection Ultraviolet Chemical

Design Steps Decision: Wastewater Treatment is Needed Basis of Design Process Selection Preliminary Design Final Design

Preliminary Design Drawing set to build consensus Process Schematic Site Plan Hydraulics

Process Schematic

Site Plan

Hydraulic Profile

Design Steps Decision: Wastewater Treatment is Needed Basis of Design Process Selection Preliminary Design Final Design

Final Design Selection and sizing of minor equipment Pumps and piping Tanks Instrumentation Aeration Equipment Concrete Electrical

Coordination of All Disciplines

Final Design Communicate what is to be built to contractor Basis of cost estimate for Owner and cost quote from contractor Represents details from all disciplines

Thank You

Mark O. Liner, P.E. Naturally Wallace Consulting Lagoon Technology Mark O. Liner, P.E. Naturally Wallace Consulting

Lagoon ??? More lagoon systems in the USA than any other system Easy to build and maintain Very little is written about them Not much to say!!!

Types of Lagoons Anaerobic Facultative Polishing Partial Mix Complete Mix High Performance Batch Reactor Equalization/Storage Evaporation/Cooling

Lagoon Applications Covered Agricultural Contaminated Stormwater Lagoons are everywhere. Small towns, pig farms, paper mills, airports. Seems like everyone has one. Call it a pit, a pond, Contaminated Stormwater Mine Water Treatment Advanced Domestic Wastewater

What is it??? Constructed basin Lined Water level control Sludge Lagoon in Slovenia

What are they good for? What are lagoons good for? Solids Management Removal and Storage Oxidation of Organics (BOD) Naturally Mechanically Hydraulic Equalization Smooth out the peaks

How do you design??? Function related to design Water depth Surface area Detention time Anaerobic Lagoon (6.0 meter deep) Facultative Lagoon (1.5 meter deep)

Solids Removal What are solids? Sedimentation rate Organics (bacteria) Inorganics (silt and sand) Algae Sedimentation rate Wind/Turbulence Type of solids Concentration of solids

Settling Time

Sludge Accumulation Settled solids undergo digestion and compaction over time Rule of Thumb: 0.5 m3/m3/d sludge accumulation for domestic wastewater

Sludge Accumulation Plot

Algae Employed in facultative lagoons Diurnal cycle cause fluctuations in Dissolved oxygen pH Solids Measured by Chlorophyll Alpha test

Organics Removal Simplified model assumes steady state complete-mix reactor Equation:

Government Design

Advanced Design Linvil Rich Current Advanced Design Methods L. Rich Grady and Daigger Metcalf & Eddy Performance Modeling by Biomass Growth not BOD removal Same Modeling Techniques That Are Used For Designing Conventional Sewage Plants Linvil Rich

Theoretical Relationship

Anaerobic Lagoons Deep > 3 meter deep Covered Loading Grease cap Floating cover Loading 0.04 – 0.30 kg-BOD/m3/d Detention Time 1-50 Days

Aerobic Lagoons Taking oxygen in gas phase to water in liquid phase Passive = ambient transfer Active = mechanical Floating Aerators Blower and Diffusers

Aeration by Diffusers

How much oxygen? Calculate mass of oxygen required for bacterial degradation AND digestion Correct for field conditions

Mixing Lagoons have low solids Low energy/volume Large volumes!!! 1-2 W/m3 = rule of thumb

Short Circuiting

Short Circuiting

Civil Design Site Soils and Water Seal

Soils Testing for Lagoons Minimum Requirements Four borings per 0.5 acres Depth to 10’ below design floor One boring to 25’ Borings located at deepest excavation Borings at borrow pits for nature and consistency Vertical Separation 4’ between pond seal and maximum groundwater level 2’ separation permitted for synthetic liners

Lagoon Seals Percolation less than 1/16” per day at 6’ water depth Soil seals shall be clay or include bentonite Minimum thickness of 4” Synthetic Seals Greater than 30 mil thickness Anchored at berm and vented Empirical testing required to document compliance

Liner Systems Clay and Bentonite Soil Synthetic Clay Geomembrane Asphalt/Concrete

Installation of Synthetic Liner

Boot Installation

Seam Testing

Water Balance Testing Seepage rate must be less than 500 gallons per acre per day

Lagoon Equipment Aeration Covers Baffles Proprietary

Aeration Equipment Floating Mechanical Submerged Diffusers

Covers Covers Conserve heat Control odors Prevent algae

Baffles

Proprietary Systems Parkson – BioLac EDI – ATLAS Lemna – BTP Nelson Environmental EDI’s ATLAS Internal Clarifier

Berm Failure

Berm Failure

Berm Inspection

Floating Liner

Liner vent

Whale of a Liner

Thank You