68
N. M. Jais et al.
the top and centre of the tank which is known as ‘gas cap’. Indirectly, the gas caps
prevent remaining particles to enter the next tank. This tank can reduce 50–70 %
BOD, COD and TSS (PEN 2008; CAP 2011).
The sequencing batch reactor is the chamber that treats fresh market wastewater in
batches and not continuously with activated sludge process which consists of openair tank. The aeration from air injection pipes at the bottom tank with specific rate
increases aerobic bacteria growth rate. These bacteria consume organic compound
and nutrients present in wastewater, were clumped together and suspended in the
tank. The process reduced the amount of BOD and COD (PEN 2008; CAP 2011).
The stages for sequencing batch reactor are
i. Filling—filled with pre-treated from up-flow anaerobic sludge blanket,
ii. Reaction—bacteria react with the aerated wastewater, then flocs,
iii. Settling—when aeration stopped, the flocs are allowed to settle and give clear
effluent,
iv. Decanting—effluent pumped out of the tank from the top of wastewater (it does
not disturb the sludge blanket at the bottom),
v. Idling—the sequencing batch reactor idles until for the next cycle and,
vi. Sludge wasting—the excess sludge is periodically removed from the tank.
The cocopeat filter was used for this site for about one year as demonstration. The
treated wastewater is dripped through the cocopeat, to ensure the wastewater is clean
for reusing or for discharging the effluent. The effluent was reused for toilet flushing
for about a year and now currently used for cleaning the streets.
San Fernando Public Market in San Fernando City at La Union, Philippines runs
a small-scale wastewater treatment system. The main city market with 700 stalls
(sometimes up to 900 stalls on the market days of Wednesday, Saturday and Sunday).
The wastewater from septic tank then flows to the drainage canal which pose a
significant threat to the coastline city. Thus, the wastewater polluted the nearby
beaches and threatened human health in the surrounding area. The newly constructed
sewage treatment system was used to clean up the coastline at San Fernando City with
technical assistance from the United States Agency for International Development
(USAID) funded Environmental Cooperation-Asia project (PEN 2008; CAP 2011).
The flow process of wastewater treatment system at San Fernando Public Market
is illustrated in Fig. 4.5. The chlorination tank consists of a tank and supplied chlorine
to kill the remaining pathogens or bacteria in the wastewater. After dissipation, the
effluent can be recycled for toilet flushing or discharged.
Sta. Ana Public Market in Manila City, Metro Manila, Philippines which is alongside the Pasig River has 220 stalls. This public market discharges the partially treated
wastewater to the river, thereby increasing the pollution in Pasig River which is known
as the most polluted river in the world. The river is considered as ‘biologically dead’
due to the combination of this public market wastewater and domestic wastewater.
Thus, PSA, Rotary and government worked together to clean the river by constructing a sewage treatment system for this public market wastewater. This wastewater
treatment system also can be used as a model that can be replicated in other public
markets along the river (PEN 2008; CAP 2011).
N. M. Jais et al.
the top and centre of the tank which is known as ‘gas cap’. Indirectly, the gas caps
prevent remaining particles to enter the next tank. This tank can reduce 50–70 %
BOD, COD and TSS (PEN 2008; CAP 2011).
The sequencing batch reactor is the chamber that treats fresh market wastewater in
batches and not continuously with activated sludge process which consists of openair tank. The aeration from air injection pipes at the bottom tank with specific rate
increases aerobic bacteria growth rate. These bacteria consume organic compound
and nutrients present in wastewater, were clumped together and suspended in the
tank. The process reduced the amount of BOD and COD (PEN 2008; CAP 2011).
The stages for sequencing batch reactor are
i. Filling—filled with pre-treated from up-flow anaerobic sludge blanket,
ii. Reaction—bacteria react with the aerated wastewater, then flocs,
iii. Settling—when aeration stopped, the flocs are allowed to settle and give clear
effluent,
iv. Decanting—effluent pumped out of the tank from the top of wastewater (it does
not disturb the sludge blanket at the bottom),
v. Idling—the sequencing batch reactor idles until for the next cycle and,
vi. Sludge wasting—the excess sludge is periodically removed from the tank.
The cocopeat filter was used for this site for about one year as demonstration. The
treated wastewater is dripped through the cocopeat, to ensure the wastewater is clean
for reusing or for discharging the effluent. The effluent was reused for toilet flushing
for about a year and now currently used for cleaning the streets.
San Fernando Public Market in San Fernando City at La Union, Philippines runs
a small-scale wastewater treatment system. The main city market with 700 stalls
(sometimes up to 900 stalls on the market days of Wednesday, Saturday and Sunday).
The wastewater from septic tank then flows to the drainage canal which pose a
significant threat to the coastline city. Thus, the wastewater polluted the nearby
beaches and threatened human health in the surrounding area. The newly constructed
sewage treatment system was used to clean up the coastline at San Fernando City with
technical assistance from the United States Agency for International Development
(USAID) funded Environmental Cooperation-Asia project (PEN 2008; CAP 2011).
The flow process of wastewater treatment system at San Fernando Public Market
is illustrated in Fig. 4.5. The chlorination tank consists of a tank and supplied chlorine
to kill the remaining pathogens or bacteria in the wastewater. After dissipation, the
effluent can be recycled for toilet flushing or discharged.
Sta. Ana Public Market in Manila City, Metro Manila, Philippines which is alongside the Pasig River has 220 stalls. This public market discharges the partially treated
wastewater to the river, thereby increasing the pollution in Pasig River which is known
as the most polluted river in the world. The river is considered as ‘biologically dead’
due to the combination of this public market wastewater and domestic wastewater.
Thus, PSA, Rotary and government worked together to clean the river by constructing a sewage treatment system for this public market wastewater. This wastewater
treatment system also can be used as a model that can be replicated in other public
markets along the river (PEN 2008; CAP 2011).