Current through March 20, 2024
Authority: IC
15-16-1-6;
IC
15-16-1-7
Affected: IC
15-16-1-10;
IC
15-16-1-11
Sec. 9.
(a) The
total refrigeration load shall be computed as the sum of the following:
(1) Load imposed by heat flow into the tank
caused by the temperature differential between design ambient temperature and
storage temperature.
(2) Load
imposed by heat flow into the tank caused by maximum sun radiation.
(3) Maximum load imposed by filling the tank
with ammonia warmer than the design storage temperature unless facilities are
provided to safely dispose of vented vapors.
(b) More than one (1) storage tank may be
handled by the same refrigeration system.
(c) Requirements for compressors shall be as
follows:
(1) A minimum of two (2) compressors
shall be provided, either of which is of sufficient size to handle the loads
listed in subsection (a)(1) and (a)(2). Where more than two (2) compressors are
provided, minimum standby equipment equal to the largest normally operating
equipment shall be installed. Filling compressors may be used as standby
equipment for holding compressors.
(2) Compressors shall be sized to operate
with a suction pressure at least ten percent (10%) below the minimum setting of
the safety valve on the storage tank and shall withstand a suction pressure at
least equal to one hundred twenty percent (120%) of the design pressure of the
tank. Discharge pressure is governed by condensing conditions.
(d) Requirements for compressor
drives shall be as follows:
(1) Each
compressor shall have its individual driving unit.
(2) Any standard drive consistent with good
design may be used.
(3) An
emergency source of power of sufficient capacity to handle the loads listed in
subsection (a)(1) and (a)(2) shall be provided unless facilities are provided
to safely dispose of vented vapors while the refrigeration system is not
operating.
(e)
Requirements for automatic control equipment shall be as follows:
(1) The refrigeration system shall be
arranged with suitable controls to govern the compressor operation in
accordance with the load as evidenced by the pressure in the tank or
tanks.
(2) An emergency alarm
system shall be installed to function in the event the pressure in the tank or
tanks rises to the maximum allowable operating pressure.
(3) An emergency alarm and shutoff shall be
located in the condenser system to respond to excess discharge pressure caused
by failure of the cooling medium.
(4) All automatic controls shall be installed
in a manner to preclude operation of alternate compressors unless the controls
will function with the alternate compressors.
(f) Requirements for separators shall be as
follows:
(1) An entrainment separator of
suitable size and design pressure shall be installed in the compressor suction
line. The separator shall be equipped with a drain and gauging
device.
(2) An oil separator of
suitable size shall be installed in the compressor discharge line. The oil
separator shall be designed for at least two hundred fifty (250) psig and shall
be equipped with a gauging device and drain valve.
(g) The condenser system may be cooled by air
or water, or both. The condenser shall be designed for at least two hundred
fifty (250) psig. Provision shall be made for purging noncondensibles either
manually or automatically.
(h) A
receiver shall be provided that is equipped with an automatic float valve to
discharge the liquid ammonia to storage or with a high pressure liquid drain
trap of suitable capacity. The receiver shall be designed for at least two
hundred fifty (250) psig operating pressure and be equipped with the necessary
connections, safety valves, and gauging device.
(i) Requirements for insulation shall be as
follows:
(1) Where insulation is required, the
insulation thickness shall be determined by good economical design.
(2) Insulation on refrigerated tanks and pipe
lines shall be suitably waterproofed. The insulating material shall be fire
retardant; the weatherproofing shall be fire resistant.
(j) All piping shall be well supported and
provision shall be made for expansion and contraction. All refrigeration system
piping shall conform to the Refrigeration Piping Code, including current
amendments and latest edition of the same (ANSI/ASME B31.5), a section of the
American Standard Code for Pressure Piping, as it applies to ammonia.
