The DDA is the model of choice for complex and demanding applications requiring maximum process reliability.
A multinational food manufacturer was experiencing problems with the sodium hypochlorite feed, commonly known as bleach or liquid chlorine, used for disinfection in its Nebraska factory. The manufacturer needed to meet state regulations, which required 0.1 to 3.1 parts per million of free chlorine, but this presented a number of challenges. The metering pumps were located outside the facility in a structure vulnerable to the harsh weather conditions of Nebraska. During the hot summer, the bleach tended to degas, causing priming issues for engineering and maintenance staff.
Indeed, the staff had to check on the pumps at the start of every shift in order to record over- and under-dosage caused by fluctuating levels of pressure. They also had to re-prime the metering pumps after every weekend in order to compensate for the degassing nature of bleach.
The manufacturer had tried a number of pump products but always suffered the same challenges. That is until Jeff Burch of Hutcheson Engineering introduced the staff to the Grundfos DDA digital dosing pump, the model of choice for complex and demanding applications requiring maximum process reliability. The DDA pump, which featured patented sensor technology for measuring flow and monitoring pressure, was able to overcome the problems of the previous pumps.
With a turndown ratio of 3000:1, the stepper motor technology allows the pump to run a nearly continuous feed of bleach to the plant’s injection line – a vast improvement compared to the pulsation that caused leakages along the system’s piping. The DDA’s built-in pressure sensors automatically adjust performance to meet actual desired output regardless of pressure fluctuation, eliminating the manufacturer’s concerns of underfeeding the chemical when pressure was high and overfeeding when pressures were low. The auto deaeration feature continuously discharges gas that accumulates, thereby reducing their weekly maintenance need of having to reprime the pump. The top and bottom scaling of the analog signal further improves accuracy on the actual feed, improving cost savings and reducing chemical waste.
As a result, the DDA pump has been error- and maintenance-free for the past 18 months. To learn more about the Grundfos DDA digital dosing pump, visit the product page.