N.J. Admin. Code § 12:90-4.7

Current through Register Vol. 56, No. 23, December 2, 2024

Section 12:90-4.7 - Steam boiler blowdown tanks and receivers

(a) This section shall apply to the construction and installation of steam boiler blowdown tanks and receivers.

(b) Pressure or unvented blowdown tanks:

1. A blowdown tank subject to possible maximum steam boiler pressure shall be constructed for the boiler pressure and stamped ASME and registered with the National Board.

2. A blowdown tank shall be used whenever the blowdown from any steam boiler is disposed in a sewerage or other interconnected system, and placed between the boiler and the sewer or such system.

(c) Atmospheric or vented blowdown tanks:

1. The outlet from the blowdown tank shall be not less than twice the area of the boiler blowdown pipe and made to extend internally to within six inches of the bottom of the tank.

2. A vent pipe, at least twice the diameter of the inlet, shall lead to the outside atmosphere. Vents shall be as direct as possible to the outside atmosphere and discharge at a point not less than seven feet above grade. No valve, water pocket, or other obstruction shall be in this line.

(d) Construction of blowdown tanks:

1. The minimum metal thickness of blowdown tanks, whether of the pressure or atmospheric type, shall be not less than 5/16 inch.

2. All blowdown tanks, whether of the closed or vented type, shall have approved openings for cleaning and inspection, and shall be capable of a maximum discharge at 150 degrees Fahrenheit at five psig.

3. The capacity of blowdown systems shall be sufficient to prevent discharges from exceeding 150 degrees Fahrenheit at five psig.

(e) Centrifugal type separators:

1. Centrifugal type separators shall be built and stamped in accordance with the ASME Code and may be used as provided in (e)2 and (e)3.

2. Separators may be used when a safe point of discharge is available and the pressure and temperature conditions at the point of discharge need not be considered.

3. Separators may be used as an auxiliary to a blowdown tank but may not be used in lieu of a conventional blowdown tank in those installations requiring a blowdown tank.

(f) Drawings of acceptable blowdown tanks and equipment:

1. Shown below are acceptable blowdown tanks and equipment as Figures 4.7(f)1 and 4.7(f)2.

(g) Repairs and alterations to blowdown tanks and separators shall be in accordance with N.J.A.C. 12:90-5.1 2.

Data in image

N.J. Admin. Code § 12:90-4.7

Amended by R.1990 d.24, effective 1/16/1990.
See: 21 New Jersey Register 3247(a), 22 New Jersey Register 235(a).
Amended by R.1994 d.599, effective 12/5/1994.
See: 26 New Jersey Register 3810(a), 26 New Jersey Register 4828(a).
Amended by R.1996 d.588, effective 12/16/1996.
See: 28 New Jersey Register 4060(a), 28 New Jersey Register 5224(a).
In (b)1, changed stamping requirement and added registration requirement.