The Texas A&M Wastewater Treatment Plant uses conventional activated sludge treatment processes to treat wastewater from campus buildings. It is designed to treat up to 11,700 pounds of biochemical oxygen demand per day from a population equivalent of 69,900 people. The plant utilizes primary and secondary clarification, aeration, ultraviolet disinfection, and land application of biosolids to treat wastewater and remove contaminants before water is recycled or biosolids are used as fertilizer. Laboratory testing ensures the plant meets regulatory requirements for effluent water quality.
2. Texas A&M Wastewater Treatment Plant
Providing a Cleaner Environment Through Water and Bio-solids Recycling
2
3. Texas A&M Wastewater Treatment Plant
Providing 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
3
4. Texas A&M Wastewater Treatment Plant
Providing a Cleaner Environment Through Water and Bio-solids Recycling
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
4
5. Texas A&M Wastewater Treatment Plant
Providing a Cleaner Environment Through Water and Bio-solids Recycling
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
5
6. Vortex Grit Removal System
Grit
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
7
7. 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
8
8. 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
9
9. Secondary Clarifier
The 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.
WWTP houses two 70’ x 16’ tanks
11
10. 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
12
11. 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
13
12. 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
15
13. Land Application of Biosolids
UTILIZE 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.
16
14. Wastewater Laboratory
ENSURES REGULATORY
COMPLIANCE GOVERNED BY TCEQ
Testing Includes:
BOD5 & TSS-
Daily Avg. 20 mg/l
7 Day Avg. 30 mg/l
Daily Max 45 mg/l
E-Coli
Daily Avg. 126
Daily Max 394
Ammonia Nitrogen
Daily Avg. 12 mg/l
Ph – not less than 6.0 nor greater than 9.0
Minimum D.O. 2.0 mg/l
Flow- 4.0 MGP; 2 hr. peak flow 9.0 MGD
17