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C. Bacotiu et al.
• replacement of the microstrainer’s drive system with a system capable of supporting the weight of the stainless steel fabric, which includes:
– replacement of the backwashing system, including the pumps;
– installing a flow meter on the discharge pipe of the microstrainer’s washing
station;
– provision of electrical sluice gates to the microstrainers.
• installing an automatic control system for the microstrainers (for automatically
controlling the rotational speed of the drum drive depending on the turbidity of
raw water);
• installing four turbidity sensors on the microstrainer’s supply pipes;
• replacing the valves at the entrance of the microstrainers with electric valves,
which can be controlled according to the water level in the distribution chamber
located before the microstraining station;
• installing an automatic dehumidification system and restoration of the microstraining station’s building.
Rehabilitation of the existing clarifiers
The clarifiers have the role of retaining the suspensions in the raw water, after the
coagulation-flocculation process, and concentrating and discharging the resulting
sludge. The station is composed of:
– 3 clarifiers with mechanical recirculation of the sludge, each having a 30 m diameter and a nominal capacity of 800 l/s, equipped with variable speed mixers and
lamellar modules.
– 1 solids contact clarifier with mechanical recirculation, having a 48 m diameter
and a nominal capacity of 1000 l/s, equipped with a rotating scraper bridge. From
all the three clarifiers, water is gravitationally transported to the filtration lines.
The proposed improvement works for this stage of treatment are:
– the rehabilitation of the structure for the four clarifiers;
– the rehabilitation or replacement of the scraper bridge;
– the rehabilitation of the electrical and automation system for the radial clarifiers,
replacing the ordinary electrical control panel with an electrical and automation
panel for the control of the scraper bridge;
– replacing the vertical mixers in the reaction chambers (one pair in each reaction
chamber) of the three solids contact clarifiers. It is also necessary to replace the
electrical panels for the supply and control of the mixers;
– replacing the lamellar modules, as well as their fastening and support structure;
– replacing the valves on the sludge discharge pipes, with electric gate valves, which
can be programmed to open at a certain time or depending on the turbidity measured
in the sludge pockets;
– replacing the existing flow control valves on the inlet pipe with electrically operated
control valves.
– installing turbidity sensors in the clarifier’s sludge pockets;
C. Bacotiu et al.
• replacement of the microstrainer’s drive system with a system capable of supporting the weight of the stainless steel fabric, which includes:
– replacement of the backwashing system, including the pumps;
– installing a flow meter on the discharge pipe of the microstrainer’s washing
station;
– provision of electrical sluice gates to the microstrainers.
• installing an automatic control system for the microstrainers (for automatically
controlling the rotational speed of the drum drive depending on the turbidity of
raw water);
• installing four turbidity sensors on the microstrainer’s supply pipes;
• replacing the valves at the entrance of the microstrainers with electric valves,
which can be controlled according to the water level in the distribution chamber
located before the microstraining station;
• installing an automatic dehumidification system and restoration of the microstraining station’s building.
Rehabilitation of the existing clarifiers
The clarifiers have the role of retaining the suspensions in the raw water, after the
coagulation-flocculation process, and concentrating and discharging the resulting
sludge. The station is composed of:
– 3 clarifiers with mechanical recirculation of the sludge, each having a 30 m diameter and a nominal capacity of 800 l/s, equipped with variable speed mixers and
lamellar modules.
– 1 solids contact clarifier with mechanical recirculation, having a 48 m diameter
and a nominal capacity of 1000 l/s, equipped with a rotating scraper bridge. From
all the three clarifiers, water is gravitationally transported to the filtration lines.
The proposed improvement works for this stage of treatment are:
– the rehabilitation of the structure for the four clarifiers;
– the rehabilitation or replacement of the scraper bridge;
– the rehabilitation of the electrical and automation system for the radial clarifiers,
replacing the ordinary electrical control panel with an electrical and automation
panel for the control of the scraper bridge;
– replacing the vertical mixers in the reaction chambers (one pair in each reaction
chamber) of the three solids contact clarifiers. It is also necessary to replace the
electrical panels for the supply and control of the mixers;
– replacing the lamellar modules, as well as their fastening and support structure;
– replacing the valves on the sludge discharge pipes, with electric gate valves, which
can be programmed to open at a certain time or depending on the turbidity measured
in the sludge pockets;
– replacing the existing flow control valves on the inlet pipe with electrically operated
control valves.
– installing turbidity sensors in the clarifier’s sludge pockets;