Precious Metals Recovery LLC RCRA Permit Application Dry Hills ...

30.0 MISCELLANEOUS TREATMENT – 40 CFR 270.23 & 264.600
Subpart X
Two treatment systems will be permitted as miscellaneous treatment unit systems at the proposed
TSF: the retort, along with an associated afterburner (defined as an “oxidation unit” under the
RCRA regulations), as well as the caustic leach treatment filter press. These are not regulated
under other subparts of the RCRA regulations and are described in this section.
Note: the oxidation unit referenced in this section does not refer to the oxidation reactor (tank)
for the SO2 scrubber bleed. There is a separate tank to oxidize the bleed from the SO2 scrubber,
which is not defined as miscellaneous treatment.
30.1 Retort – 40 CFR 270.23(a), 270.23(d), & 264.601
The retort will be the primary treatment unit to reclaim elemental mercury from mercury-bearing
materials accepted for treatment at the proposed TSF, as well as for mercury-bearing wastes
generated by the proposed TSF. The retort does not meet the definition of an incinerator, boiler,
or industrial furnace, because it is an electric thermal treatment unit with no flame. Mercurybearing
materials are heated in the retort and the mercury is recovered as it vaporizes and
separates from the feed, rather than being destroyed.
The retort will be located in the process area (see Section 1.2.3) followed by the afterburner
located in the process area.
Retorting is an effective means to recover mercury. The retort is designed to recover elemental
mercury with a purity content of 99.5% or greater.
30.1.1 Retort Description – 40 CFR 270.23(a) & 264.601
The retort circuit is primarily designed to treat spent activated carbon and filter cake from the
calomel treatment caustic leach circuit described in Section 1.2.2. The retort may also treat other
mercury-bearing materials.
Dimensions of the retort circuit are 13.6 feet long by 8.1 feet wide by 12.4 feet tall. The system
includes the two retort domes, a condenser, an air cooling unit, and a controller. The retort circuit
is described in detail and illustrated in Section 1.2.3.
30.1.2 Retort Design – 40 CFR 270.23(a)(1)
The retort will be designed, fabricated, and supplied as a commercially available item by a
qualified vendor with experience in such applications (e.g., MRT Systems). The vendor will
provide a certification for the unit. The retort for this permit application has been designed by
MRT Systems. Drawings for the retort and associated equipment included in Appendix 30-A.
The retort circuit is described in detail and illustrated in Section 1.2.3.
PMR RCRA Permit Application, Dry Hills Facility Page 136
JBR Environmental Consultants, Inc. | HATCH March 2013