Dilution Systems provide accurate automatic chemical blending or mixing of two or more liquids continuously from storage tanks or shipping containers such as railcars or tank trucks. Powell Dilution Systems usually refer to skid mounted systems with all required piping, instrumentation, and controls supplied with the package.
Depending on the liquid being mixed or blended, stainless steel, PTFE lined piping, polyethylene, and other piping products will be utilized. The systems can be constructed to handle different liquids, and this may require higher-level piping to meet the more difficult products.
If required, cooling of the final product is typically done with plate and frame heat exchangers. Many different alloys, including 316 SS, Hastelloy C2000, Titanium, and others are available depending on compatibility. In some cases, shell and tube heat exchangers may be required, of which the materials are varied. Typically, a cooling water is used, and the towers and pumps can be supplied by Powell. Depending on the application, air-cooled, or water-cooled packages can be supplied by Powell.
Most dilution systems will have pressure, temperature, level transmitters, flow measurements, and flow control devices. Depending on the client’s preference, typical choices of instruments are Rosemount, Yokogawa, Endress Hauser, ABB and many more. Flow measurements are typically mass meters or magnetic flow meters and flow control valves are usually Manoneilan or Atomac. In many cases, the choice of instrumentation is driven by the location of the installation.
Most control systems for Powell Dilution Systems are standalone PLC driven with the occasional blending system being directly connected to the customer’s DCS without local control. The choice of PLC hardware is customer driven. These control systems can provide data logging and an Ethernet connection to any customer DCS. These PLC control systems also typically provide VPM options for the customer to allow the manufacturer to troubleshoot the system anywhere in the world.
Usual choices for pumps are magnetic drive pumps with no seals. These can be 316 SS, Tefzel Lined and other choices. Some high viscosity applications require a positive displacement pump in lieu of a standard centrifugal pump.
Some customers will provide their own motor starter/disconnects in a central motor control room. However, if desired, remote mounted motor starter disconnects on the package can be installed. Often, a motor control section(s) can be furnished for customer installation. If required, soft start and variable speed drives can be included in the installation. When motor controls are used either by the customer or by Powell, Ethernet can be used for the communication from the PLC to the motor starter assembly.