The textile industry in India uses 1,608 MLD (million liters per day) every day for several of its water intensive processes. The used water from these industries if not filtered and let out or reused, tends to pollute the surrounding water and add to the water woes of the country.
As per the recent regulation and a positive measure, many textile companies have begun embracing global best practices such as Zero Liquid Discharge (ZLD) to reuse water. This process ensures that all the water used in the textile processing is recovered optimally for reuse and thereby enabling these companies to reduce their water footprint. However, some of the challenges associated with ZLD is the high OPEX cost owing to a process called ‘Mechanical Vapor Recompression Evaporation’ (MVRE). This process is critical to increase the water concentrate before the final salt recovery after the fourth stage of the Reverse Osmosis (RO) in ZLD. However, MVRE is an expensive process as it requires high kW motor and steam. This makes the MVRE process of ZLD financially unviable for many.
Therefore the common effluent treatment plants (CETPs), end users and key OEM’s are looking at fifth stage RO as an alternate to MVRE – as it can help reduce the OPEX cost from Rs. 4,00,000 per liters to Rs. 50,000-60,000 per liters. The fifth stage RO requires high pressure pumps and membranes in the range of 60bar min-120bar to perform its functions.
Leading textile company in Erode had decided to use the fifth stage RO for the capacity of 30m3/h at 80bar pressure in its ZLD Process to reduce the energy costs in 2019. However, it had faced frequent failures and service issues in plunger pumps which were used in such high-pressure applications. This company then began looking for more efficient alternates.
They had approached Grundfos with their challenges of frequent failures and service issues in plunger pumps used earlier in such high-pressure applications. Grundfos, a global leader in advanced pump solutions and a trendsetter in water technology supplies a broad range of pump systems and solutions to maintain industrial processes, especially in water and wastewater treatments.
Grundfos provided a solution with to this textile company – a BMS HS (High Speed) pump and BM pumps to cater to this need for high pressure application. After the successful commissioning and handover of the project in November 2019, these Grundfos pumps helped to significantly cut down their running costs and in smooth delivering of the required performance.
Product specifications
Grundfos used its BMS 17-22 HS85kw MMG and BM 17-40R22kw pumps and with MPC controllers to augment the Fifth Stage RO process of the ZLD process.
The BM range of boosters are ideal for Reverse Osmosis and filtration applications with the capacity to perform optimally under high pressure conditions.
The BMS HS solution can manage pressure up to 82.7bar efficiently and the motor has a speed range of 4000 to 5500 rpm. Coupled with an asynchronous motor, these solutions prove to be extremely efficient for the given application, bringing the energy savings to a larger extent for the customer. The high-speed motor ensures that BMS HS is compact and light-weight making its deployment hassle-free. Their flexible nature ensures that it could be integrated with any water treatment system.
Additionally, these solutions are equipped with a variable frequency drive with a communication module to be able to adapt to changing needs.
Outcome
- BM and BMS pumps have increased reliability by bringing about uninterrupted operations in the fifth stage of the RO for ZLD
- It has brought about a significant cost reduction as these pumps are highly energy efficient
- The variable frequency drive with a communication module helps ensure that the pressure, flow, and speed are optimally managed for its varying requirements
- MPC controller enables automatic operations and ensures that safety precautions for pumps are in place without the need for any manual intervention