ETP Plant / Waste Water Treatment in Chandigarh – Case Study

Ocean Non Wovens supplied 43500 sq mtr of 1.5mm HDPE geomembrane for an effluent treatment plant (ETP) and wastewater treatment project in Chandigarh. In a treatment plant, the liner keeps untreated and partly treated wastewater inside the ponds and basins, out of the soil and groundwater below.

Product – HDPE Geomembrane 1.5mm

Quantity – 43500 sq mtr

Location – Chandigarh

Problem

Wastewater from homes and industry carries pathogens, organic matter and chemicals. Discharged untreated, it pollutes groundwater, drains and rivers downstream, contaminates crops and drinking water, and harms the plants and animals that live in or near the water. Treated properly, the same water can be reused for irrigation, landscaping and industrial purposes, which matters as water demand in Indian cities keeps rising.

Indian sewerage design norms (the CPHEEO manual) assume that about 80% of the water supplied to households returns as wastewater. Much of the sewage generated in India still reaches drains and water bodies with little or no treatment. Chandigarh, like other growing cities, needed treatment capacity to deal with this.

Solution

Treatment plants, whether large central plants or smaller decentralised units close to where the wastewater is produced, rely on ponds, lagoons and basins that must not leak. Decentralised plants are often used for areas not connected to a sewer network or for new developments, because they need less capital and simpler operation. Like any plant, they work only if properly designed, operated and maintained.

HDPE geomembranes are widely used to line containment basins, treatment lagoons, sludge beds and tanks holding process wastewater, chemicals and petroleum products. They suit this duty because:

• Very low permeability: a welded HDPE liner stops wastewater seeping into the ground.
• Chemical resistance: HDPE resists a wide range of acids, alkalis, salts and organic compounds found in sewage and industrial effluent.
• UV resistance: carbon black in the sheet protects exposed side slopes above the water line from sunlight.
• Works submerged: the liner performs continuously under water and does not rot.
• Strength: 1.5mm sheet has the tensile strength and puncture resistance to cope with installation, maintenance traffic and desludging.

For a liner like this, sheets are joined on site by double-track fusion welding, and seams are tested by air pressure (ASTM D5820) and vacuum box (ASTM D5641) before the basins are filled. GRI-GM13 is the usual reference specification for HDPE geomembrane properties.

See more case studies of Ocean HDPE geomembranes in water and wastewater containment, or contact the team about liner thickness and supply for your plant.