Challenge

An east coast mega-city's energy company provides steam as a means of heating and cooling the city's buildings through underground piping. Originally, raw water which is converted to steam was treated by the the company's own deionization (DI) treatment plant. As a result of safety concerns regarding the transportation and handling of acid and caustic chemicals used in the treatment plant, the company decided to converted the cation vessels to zeolite softeners. Shortly after, however, the city began to experience pipe failures caused by condensate corrosion. The low pH condensate is highly aggressive to piping systems, causing increasing costs for maintenance and repair. The energy company decided to conduct a pilot study using DI water to change the quality of the raw water which in turn improved the quality of steam.

Solution

The energy company decided to use mobile DI trailers from Siemens Water Technologies to provide an immediate alternative to softened water. Four mobile DI trailers were installed to make boiler feed water for the site. At the height of steam use, one to two trailers are exchanged per day to meet the demands of the city. An on-site service technician works with the energy company to ensure quality and quantity of water is provided on a daily basis.

Results

Siemens was able to provide this energy provider with a temporary solution to their long term requirement. The original two-year contract has guaranteed the city the quality and quantity of water required to keep steam available on demand. With the additional resin capacity, the system is exceeding the guaranteed 1.75 million gallons per day (mgd) and providing over 2 mgd to the facility.