Case study of solid waste management using different locations

This study shows delhi waste management

1. CASE STUDY FOR GROUP 1

2. Scenario A town with a population of about 75,000 has been operating a Faecal Sludge Treatment Plant (FSTP) for the last five years. The plant, with a capacity of 30 KLD , uses a combination of stabilization ponds and constructed wetlands for faecal sludge (FS) treatment. Recently, the local environmental agency has raised concerns regarding the FSTP's performance, citing complaints from nearby communities about odour and inadequate treatment of effluent, particularly during the monsoon season . The plant management has collected data to investigate the issues. 2

3. Scenario (Faecal Sludge (FS) Analysis) pH : 6.2 Total Solids (TS) : 15,000 mg/L Chemical Oxygen Demand (COD) : 28,000 mg/L. Biochemical Oxygen Demand (BOD) : 9,500 mg/L Total Nitrogen (TN) : 850 mg/L Pathogens Helminth Eggs: 10 eggs/g TS Faecal Coliforms: 2,500 MPN/100 mL 3

4. Scenario (Treated Water Analysis) pH : 7.1 COD : 120 mg/L BOD : 60 mg/L Total Suspended Solids (TSS): 90 mg/L Ammonia : 45 mg/L. E. coli. : 2,000 MPN/100 ml 4

5. Scenario (Biosolids Analysis) Moisture Content: 75% Organic Matter: 45% Pathogens: Helminth Eggs: 15 eggs/g TS E. coli: 1500 MPN/100 mL 5

6. Data Interpretation Missing Data: Rainfall data, area of constructed wetland. Hydraulic retention time (HRT), sludge accumulation data. DO, temperature, QA/QC details of sampling. E. Coli information is missing in FS, Faecal Coliform is missing in treated water. Without these, true plant loading and efficiency cannot be fully assessed. 6

7. Data Interpretation Trends: Identified as it is a very high-strength FS 7 Parameter FS Treated water Bio Soild COD 28,000 mg/L 120 mg/L --- BOD 9,500 mg/L 60 mg/L (limit < 30) --- pH 6.2 7.1 --- TSS --- 90 mg/L (above ~30 mg/L discharge norm) --- Ammonia --- 45 mg/L (indicates poor nitrification) --- E. Coli --- 2000 MPN/100 mL (above permissible ≤1000) 1500 MPN/100 mL (above permissible ≤1000) Helminth eggs 10 eggs/g TS (unsafe; standard <1 egg/4g) --- 15 eggs/g TS (unsafe; standard <1 egg/4g)

8. Data Interpretation Non-compliance: Effluent fails on BOD, TSS, ammonia, and pathogens. Biosolids fail on helminth eggs, E. coli and Moisture content (poor drying), unsafe for reuse 8

9. Root Cause Analysis Undersized Capacity: Plant only 30 KLD for ~75,000 population → severe overloading, reduced retention, sludge build-up. Monsoon surges worsen performance and cause odour. 9

10. Root Cause Analysis Technology Limitations: Ponds/wetlands handle organics but are poor for pathogen removal. No disinfection step → explains high effluent E. coli. Wetlands stressed by high-strength FS (not just greywater). 10

11. Root Cause Analysis Sludge Handling Issues: Helminth eggs increased in biosolids → poor drying/composting and possible recontamination. Lack of temperature/pH control prevents pathogen kill. 11

12. Solution Development Short-term (Immediate fixes): Add chlorination/UV disinfection for effluent. Increase desludging of ponds/wetlands. Stop biosolid reuse until pathogen safety is achieved. Developing a Hybrid Constructed Wetland (horizontal and vertical) with plants having high removal efficiency such as Phragfites australis, Typha latifolia, Canna indica. Quick, low-cost measures reduce immediate health risk. 12

13. Solution Development Medium-term (1–6 months): Install TSS polishing units (sand/lamella filters). Add aeration (mechanical/facultative upgrade) to improve BOD & ammonia removal. Upgrade sludge drying/composting with lime co-composting for helminth kill. Improves compliance with BOD, TSS, pathogen standards. 13

14. Solution Development Long-term (Structural upgrades): Expand plant capacity or co-treat with nearby STPs. Consider hybrid/mechanical systems (MBBR, SBR) for reliable year-round performance. Establish real-time monitoring + seasonal contingency plans. Covering the constructed wetland area with solar panels, using that power for aeration. 14

15. Summary 15 Problem Cause Solution BOD = 60 mg/L (>30) Overloading, short HRT, low aeration Add aeration, expand capacity TSS = 90 mg/L (>30) Solids washout, poor settling Sand/lamella filters, better desludging Ammonia = 45 mg/L (high) No nitrification stage Introduce aeration/biological polishing E. coli = 2000 MPN/100 mL (>1000) No disinfection step Chlorination/UV Biosolids helminth eggs = 15/g TS (>0.25/g) Inadequate drying/composting Lime stabilization, thermophilic composting Odour complaints Anaerobic sludge build-up Frequent desludging, aeration

16. Thanks! Any questions? You can find me at @username [email protected] 16