During the replacement of an aging central steam plant, the operating efficiency and sustainability depended on careful selection and specification of condensing hot water boilers. Fire tubes condensing boilers are used in the new heating plant design.
To select the most appropriate boiler, the engineer must considered the following specifications: local code requirements, cost impact, emission regulations, floor space, fire tube condensing boiler control, boiler heat ex-changer, flue material and location, drain required, hot water return temperature, minimum flow to the boiler, operating weight of the equipment, heating coil requirements, warranty coverage, and service personnel available in the area. The engineer also must consider high turn-down of the boiler, because it might reduce short cycling when demand is low. If the boiler meets the actual system demand, it can reduce fuel cost for the building owner.
For the project, major consideration was given to local codes, space requirements, boiler control, and emission reductions. The only way to install the condensing boilers at the facility was to engage the condensing boiler manufacturer to work together allowing variance approval, before the units could be installed.
Condensing boiler emissions regulations:
The boiler industry faces more stringent NOx emission regulations from the EPA. For boilers greater than 2000 MBh, a third-party test is required and NOx should be below 9 ppm. Annual inspections are required as well.
In 2011, the EPA issued a new regulation for boiler maximum achievable control technology, known as MACT. This rule is known as the National Emission Standard for Hazardous Air Pollutants (NESHAP).
To determine the emission limits for NESHAP, EPA and PA DEP use the MACT approach; the regulation was effective in 2012.
The NESHAP regulations define an area source of air emissions as any stationary source or group of stationary sources that annually emit in aggregate less than 10 tons...