Wastewater Treatment Plant Tour

DIVISION OF ADMINISTRATIONUTILITIES & ENERGY SERVICES

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Texas A&M Wastewater Treatment PlantProviding a Cleaner Environment Through Water and Bio-solids Recycling

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Texas A&M Wastewater Treatment PlantProviding a Cleaner Environment Through Water and Bio-solids Recycling

Plant Overview

Texas A&M Wastewater Treatment Plant (WWTP) is a conventional activated sludge treatment facility.

Treatment of wastewater can be divided into four major groups:

Preliminary treatment Primary treatment Secondary treatment Sludge treatment and disposal

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Design Criteria Designed to treat 11,700 lb. BOD/day on a maximum monthly avg basis.

(This is a population equivalent of 69,900 persons) Load to the plant varies in proportion to the number of people on

campus

Texas A&M Wastewater Treatment PlantProviding a Cleaner Environment Through Water and Bio-solids Recycling

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Texas A&M Wastewater Treatment Plant

Unit Operations and Processes Bar Screen/Flow Metering/Influent Lift Station Grit Removal Facility Aeration Blower Building Aeration Basins Primary and Secondary Clarifiers, Sludge Pump Stations, Sludge

Thickeners, Anaerobic Digesters, Holding Tanks, and Pumping Stations

Providing a Cleaner Environment Through Water and Bio-solids Recycling

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Vortex Grit Removal SystemGrit

Heavy mineral matter found in wastewater

Will not decompose in the treatment process

Includes sand, gravel, cinder, or other solid materials that are heavier than the organic biodegradable solids in the wastewater.

Removal of grit prevents

unnecessary abrasion and wear of mechanical equipment

deposition in pipelines and channels accumulation of grit in anaerobic

digesters and aeration basins

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Primary Clarifier

Primary clarifiers are designed to provide a quiescent volume where solids are allowed to settle by gravity over a relatively long period of time (usually 2 to 4 hours).

Gravity provides a natural separation of solids and liquid in the clarifier tank.

The “clarified” liquid then flows from the primary clarifier to further treatment called secondary or biological treatment

WWTP houses 2 60’ x 10’ tanks

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Primary Pump Station

3 primary pumps transfer sludge to thickeners

2 thickener pumps transfer sludge to primary anaerobic digester

Vogelsang Rotary Lobe Pumps rated at 120 GPM

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WWTP houses two 70’ x 16’ tanks

Secondary ClarifierThe basic purpose of the secondary clarifiers is to separate solids from liquids through the process of gravity sedimentation.

The mixed liquid from the solids contact basins flows into the center of the secondary clarifier tanks through a vertical inlet pipe.

The well serves two main purposes.

It directs flow downward in a vertical flow pattern to minimize short circuiting.

Serves as a stilling basin that promotes flocculation and settling of solids.

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Secondary Pump Station

Transfer settled sludge from secondary clarifiers to aeration basin to prevent sludge accumulation and to reseed micro-organisms in aeration basin.

3 Return Activated Sludge Pumps rated at 1200 GPM

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Ultraviolet Disinfection

An ultraviolet (UV) disinfection system transfers electromagnetic energy from a mercury arclamp to an organisms genetic material, destroying the cells ability to reproduce.

Each of these systems provides dosage of 250 Mw-s/cm2

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Aeration Blowers

Introduces air into a liquid, providing an aerobic environment for microbial degradation of organic matter.

THE PURPOSE OF AERATION IS TWO-FOLD:

To Supply the required oxygen to the metabolizing microorganisms

To provide mixing so that the microorganisms come into contact with the dissolved and suspended organic matter

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Land Application of BiosolidsUTILIZE 60 ACRES LOCATED ADJACENT

TO THE WASTEWATER TREATMENT PLANT

TO INJECT BIOSOLIDS

Terragator Model 2204 Capacity 2200 gallon tank

RECYCLING BIOSOLIDS THROUGH LAND APPLICATION SERVES SEVERAL PURPOSES.

Improves soil properties such as texture and water holding capacity.

Supplies nutrients essential for plant growth, including nitrogen and phosphorous, as well as some essential micro-nutrients such as nickel, zinc and copper.

Serves as an alternative or substitute for expensive chemical fertilizers.

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Wastewater Laboratory

BOD5 & TSS-Daily Avg. 20 mg/l7 Day Avg. 30 mg/lDaily Max 45 mg/l

E-ColiDaily Avg. 126Daily Max 394

Ammonia NitrogenDaily Avg. 12 mg/l

Ph – not less than 6.0 nor greater than 9.0Minimum D.O. 2.0 mg/lFlow- 4.0 MGP; 2 hr. peak flow 9.0 MGD

ENSURES REGULATORY COMPLIANCE GOVERNED BY TCEQ

Testing Includes:

Wastewater Treatment Plant Tour

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