Section 1200-03-16-.16 - PHOSPHATE FERTILIZER INDUSTRY: WET-PROCESS PHOSPHORIC ACID PLANTS(1) Applicability The provisions of this rule shall apply to each wet process phosphoric acid plant having a design capacity of more than 15 tons of equivalent P2O5 feed per calendar day. For the purpose of this rule, the affected facility includes any combination of reactors, filters, evaporators, and hotwells commenced on or after February 9, 1977.
(2) Definitions. (a) "Wet-process phosphoric acid plant" means any facility manufacturing phosphoric acid by reacting phosphate rock and acid.(b) "Total fluorides" means elemental fluorine and all fluoride compounds as measured by reference methods specified in subparagraph .01(5)(g) or equivalent or alternative methods.(c) "Equivalent P2O5 feed" means the quantity of phosphorous, expressed as phosphorous pentoxide, fed to the process.(3) Standard for Fluorides. On and after the date on which the performance test required to be conducted by paragraph .01(5) of this chapter is completed, no owner or operator subject to the provisions of this rule shall cause to be discharged into the atmosphere from any affected facility any gases which contain total fluorides in excess of 10.0 g/metric ton equivalent P2O5 feed (0.020 lb/ton).(4) Monitoring of Operations. The owner or operator of any wet-process phosphoric acid plant, subject to the provisions of this rule shall: (a) Install, calibrate, maintain, and operate a monitoring device which can be used to determine the mass flow of phosphorus-bearing feed material to the process. The monitoring device shall have an accuracy of ± percent over its operating range.(b) Maintain a daily record of equivalent P2O5 feed by first determining the total mass rate in metric ton/hr of phosphorus-bearing feed using a monitoring device for measuring mass flow rate which meets the requirements of subparagraph (a) of this paragraph and then by proceeding according to part (5)(c)2. of this rule.(c) Install, calibrate, maintain, and operate a monitoring device which continuously measures and permanently records the total pressure drop across the process scrubbing system. The monitoring device shall have an accuracy of ±5 percent over its operating range.(5) Test Methods and Procedures (a) For determining the concentration of total fluorides and the associated moisture content, the sampling for each run shall be at least 60 minutes and the minimum sampling volume shall be 0.85 dscm (30 dscf) except that shorter sampling times or smaller volumes, when necessitated by process variables or other factors, may be approved by the Technical Secretary.(b) The air pollution control system for the affected facility shall be constructed so that volumetric flow rates and total fluoride emissions can be accurately determined by applicable test methods and procedures.(c) Equivalent P2O5 feed shall be determined as follows:1. Determine the total mass rate in metric ton/hr of phosphorus-bearing feed during each run using a flow monitoring device meeting the requirements of subparagraph (4)(a) of this rule.2. Calculate the equivalent P2O5 feed by multiplying the percentage P2O5 content, as measured by the spectrophotometric molybdovanadophosphate method (AOAC Method 9), times the total mass rate of phosphorus-bearing feed. AOAC Method 9 is published in the Official Methods of Analysis of the Association of Official Analytical Chemists, 11th edition, 1970, pp. 11-12. Other methods may be approved by the Technical Secretary.(d) For each run, emissions expressed in g/metric ton of equivalent P2O5 feed shall be determined using the following equation: Click to view Image
where:
E = Emissions of total fluorides in g/metric ton of equivalent P2O5 feed.
Cs = Concentration of total fluorides in mg/dscm.
Qs = Volumetric flow rate of the effluent gas stream in dscm/hr.
10-3 = Conversion factor for mg to g.
M P2O5 = Equivalent P2O5 feed in metric ton/hr.
Tenn. Comp. R. & Regs. 1200-03-16-.16
Original rule effective February 9, 1977. Amended effective November 6, 1988Authority: T.C.A. §§ 68-25-105 and 4-5-202.