Name: VITOR LUIZ VIANA POMBAL
Publication date: 08/02/2022
Advisor:
Name |
Role |
|---|---|
| RICARDO FRANCI GONÇALVES | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| LAILA DE OLIVEIRA VAZ OLIVEIRA | External Examiner * |
| RICARDO FRANCI GONÇALVES | Advisor * |
| ROSANE HEIN DE CAMPOS | Internal Examiner * |
Summary: The objective of this project was to evaluate the performance of a pilot wetland
treatment plant for domestical wastewater using the first stage with two modules of a
French model, applying different operational conditions. Each reservoir has
1,80x1,80x1,20 m dimentions, filled with gravel 0,1 and 3 and vegetated with Typha
domingensis. A lift tank with two parallel pumping system to make batch loads assured
the pilot feeding with raw wastewater, applied hydraulic loads of 0,3, 0,4, 0,6 and 0,8
m³/m².d to make the performancy tests. It was necessary to make adaptations such as
shadow screen installation and hydraulic feeding reduction to reduce organic stressing,
making that the system made the permanent regime in about 55 days. After 180 days
of operation, it was made the first pruning of the plants that grew up over 2 m. The
development of the biofilm and rhizosphere have an important matter in wastewater
treatment, it is WHERE part of organic matter and suspended solids are retained. The
sludge is partialy constituted of elements that make contribution in phosphorus
removal, such as calcium and iron, which induced a global efficiency of 28% of P
removal, superior of national average indicated for the first stage of this kind of wetland
filter. During applications of 0,3 m³/m².d, the P removal efficiency were 24%, equally
for 0,4 m³/m².d when it was observed the formation of the sludge deposit in a module.
Flow ratings of 0,6 m³/m².d the average efficiency of total phosphorus removal were
32% when sludge deposit was established in both reservoir, and at 0,8 m³/m².d ratings
the average was 31%. The phosphorus removal efficiency was proportional to the
growth of sludge layer, which developed in a 1,12 cm/year rating, similar to national
averages. For the other evaluated parameters, the system contributed with removals
of 53% NTK, 59% of N-NH4
+
, 21% of P-PO4
3-
, 47% of TSS, 70% of BOD, 53% of COD,
47% of turbidity and 11% of coliforms removal, those agreed with CONAMA patterns
for sewage discharge. The average treated effluent characteristics were: 17 mg NTK/L;
6,64 mg N-NH4
+
/L; 11,95 mg Ptotal/L; 9,46 mg P-PO4
3-
/L; 134,5 mg SST/L; 95,5 NTU of
Turbidity; pH of 7,5; 1,46 mg OD/L; 194,5 mg DQO/L; 99,5 mg DBO /L. These results
were in accordance with averages required by CONAMA 430 resolution of 2011.
