Effective treatment processes are instrumental in improving the quality of the treated water. Pumping solutions are used across various phases of wastewater treatment processes such as segregation, filtration and among the other steps that are involved.
Dosing pumps are particularly used for chemical treatment in the primary, secondary and tertiary levels for processes such as disinfection, coagulation, flocculation, substrate dosing and alkalinity correction. They have extended applications in the pharmaceutical, chemical, and the food and beverage industry among others.
It is important to understand the corrosive nature, viscosity and temperature of the involved chemicals to optimize the performance of the pump.
Traditional dosing regulates the dosed quantity by adjusting the stroke length and/or frequency. However, a reduction in stroke length could have an inadvertent effect on the dosing accuracy. Over the years, the utility of chemical dosing pumps has evolved with the potential to address such challenges. Equipped with adaptive controls and state-of-the-art technology, digital dosing solutions can provide any alterations in stroke speed and ensure optimum accuracy.
Grundfos: Driving intelligent dosing solutions
As a global leader for advanced pump solutions and a trendsetter for water technology, Grundfos’ chemical dosing pumps have a significant market presence. Coupled with iSOLUTIONS offering, the digital dosing pumps are used to deliver accurate chemical metering with proven reliability, easy installation, priming and calibrating.
The Grundfos range of dosing pumps can cover a large range of performance capabilities. Their several advantages include smooth continuous dosing and universal connections to existing control systems.
SMART Digital (DDA, DDC and DDE)
SMART Digital dosing solutions have heralded a new era of intelligent chemical dosing from Grundfos. Their cutting-edge drive technology, new dimensions of end-user comfort and intelligent flow control help in improving cost efficiencies while continuing to support high precision processes.
SMART DDA, DDC and DDE solutions offer powerful motors with variable speed, a universal power supply and a full PTFE diaphragm that can meet dynamic customer requirements for chemical resistance and durability.
DDA is primarily used for complex applications that need reliable processes. It provides FlowControl, FlowADAPT, integrated flow measurement and pressure monitoring. SMART Digital DDA-FCM solution has been tested by the University of Applied Sciences Weihenstephan-Triesdorf. DDA was compared with an older Grundfos dosing pump and the precision and accuracy of both these pumps were tested using water and chlorine bleach. The test results successfully declared that the accuracy of DDA is significantly superior to traditional dosing technology.
DDC offers optimal price-performance ratio with a graphic LC display in more than 28 languages. The solution’s SlowMode (anti-cavitation) capability and calibration mode allows it to operate highly viscous chemicals efficiently.
DDE is a cost-effective model of SMART Digital solutions with a maximum turn-down ratio of 1:1000 and 1:800. The solution is integrated with functions such as pulse control, external stop function and an empty level signal. They are ideal for dosing applications in OEMs.
SMART Digital range of solutions are available in two sizes. SMART Digital S can manage a dosing flow up to 120 l/h, pressure up to 16 bar and a turn down ratio of up to 1:3000. SMART Digital XL on the other hand can manage a dosing flow of up to 200 l/h, pressure up to 10 bar and a turn down ratio up to 1:800.
For example, A municipal wastewater treatment facility near Frankfurt, Germany were facing challenges associated with chemical reduction and need to save on operating costs. In order to address this, they installed a dosing station with two Grundfos SMART Digital XL DDA-FCM dosing pumps to reduce the phosphate levels in the wastewater by accurately dosing precise levels of iron and chloride. The user-friendly solution was also successful in enabling easy operations and monitoring the wastewater operations.
DME Digital Dosing
This dosing solution effectively combines precision with user- friendly operations and covers large dosing quantities from 60 l/h to 940 l/h with a few variations.
Their powerful stepper motor improves the overall accuracy of the solution as it optimizes the control over the stroke speed. They are easy to install, and the pump can be set to dose the precise quantity required for a specific application. With a turndown ratio that is 10 times better than that of conventional dosing pumps, DME also provides flexibility and optimal priming and displacement of liquids. They have applications in industries for pulp and paper, textiles, food and beverages, drinking water treatment and industrial process water and wastewater treatment.
The capabilities of the DME digital dosing solution can be explained by understanding its function in a desalination plant near Chennai, Tamil Nadu. The seawater desalination plant was a source of drinking water for a large population and could draw up to 230 million liters of seawater each day in order to produce 100 million liters of potable water every day. Chemical adjustment was an integral part of desalination and required customized dosing solutions. 28 Grundfos DME pumps were installed in the facility and have been successfully operating ever since. The solution has been able to dose chemicals accurately and remove salts from the seawater. According to plant officials, it has also contributed to the longevity of the desalination plant.
Role of iSOLUTIONS in chemical dosing
iSOLUTIONS can typically augment the utility of a chemical dosing pump. In critical applications, it is important to ensure safe dosing of chemicals for continuous operations.
The digital solution can fulfill the required safety parameters while creating an optimal combination of pumps, drives and other components to cater to specific applications with a keen understanding of the customer requirement.
Digital solutions are expected to have an increasing role in dosing and is expected redefine its utility and applications. The increasing range of dosing requirements and current challenges could enable gradual adoption of these intelligent solutions in order to bypass challenges and surpass customer expectations.
Authored by: Girish Laxmeshwar, Associate Vice President, Business Development, Grundfos India.