Housing & Urban Development Achieves Improved ROI with Upgraded Humidification System

Requirements

The project required high quality water with low energy usage. Space and installation access were limited requiring a compact footprint design. Since the project investment is based on energy savings wasted energy was not acceptable. Humidification systems are typically used during the winter months and thus the water supply is typically cold requiring a system that produces the required capacity at lower design temperatures than are standard for most RO systems. Chlorine is removed prior to the RO system and thus the treated water is free of chlorine which does not get added back in because it would cause corrosion in the air handling units. Thus the stored RO water must be sterilized by some other method to ensure the water is free of biological contaminants.

Strategy

Mee Industries provided a packaged Reverse Osmosis system with integrated storage, distribution & UV circulation. All components where handled by a single control enclosure with a PLC capable of communicating with the Meefog control system as well as the building automation system (BAS). RO system performance is based on many factors including temperature. A typical system is designed to provide the rated capacity at a water temperature of 77 °F (25°C) which is not realistic for humidification systems because they are used in the winter when the water temperature is colder.

The Mee Water system is designed to provide the rated capacity at a temperature as low as 50 °F (10°C). Since the required operating pressure varies for the system based on factors such as temperature, the RO system could be considered energy in-efficient. However variable frequency drives were included on the motor to ensure no energy was wasted when producing the required capacity for the system. The integrated distribution pump also includes a variable speed drive to reduce energy consumption based on the humidification demand.

The UV circulation system allows the non-chlorinated water to be sterilized in the circulation loop to prevent the proliferation of biological material in the stored water. The fully integrated system ensures that the water level is monitored and circulation is carried out especially during humidification system downtimes when the water would otherwise. become stagnant in the storage tank.

With all equipment coming from a single supplier the installation and commissiong was extremely simple. The water capacity and quality was exactly in line with the humidifcation system needs.