1. A radiation-monitoring diagnostic hodoscope system for producing an approximate image of radiation-producing components within and below a pressure vessel of shutdown nuclear plant, said system comprising:
A) at least one gamma-radiation-monitoring hodoscope unit adapted to detect gamma radiation in a limited substantially-straight narrow radiation beam of less than 50 degrees and in at least one specific gamma-energy range, said at least one hodoscope unit comprising:
1) a collimating means adapted to produce said narrow radiation beam and
2) at least one radiation detector adapted to produce electrical signals corresponding to intensities of gamma radiation in said at least one specific gamma energy range;
B) a positioning means for positioning said at least one hodoscope unit so as to accumulate sufficient radiation data representing radiation intensity and gamma energies in a sufficiently large number of narrow radiation beams to create said approximate image of said gamma radiation-producing sources within and below said pressure vessel; and
C) a computer processor programmed with an algorithm adapted to associate said gamma or neutron radiation data so as to produce said approximate image of said radiation-producing components.
2. The system as in claim 1 wherein the at least one specific gamma energy range is at least two specific gamma energy ranges.
3. The system as in claim 1 wherein the processor is programmed to produce an approximate one-dimensional image.
4. The system as in claim 1 wherein the processor is programmed to produce an approximate two-dimensional image.
5. The system as in claim 1 wherein the processor is programmed to produce an approximate three-dimensional reconstructed image.
6. The system as in claim 1 wherein said system also comprises at least one neutron-radiation monitoring hodoscope.
7. The system as in claim 1 wherein said systems comprises at least one neutron- and gamma-radiation-monitoring hodoscope.
8. The system as in claim 1 wherein the nuclear plant is a boiling-water nuclear plant.
9. The system as in claim 1 wherein the nuclear plant is a pressurized-water-cooled nuclear plant.
10. The system as in claim 1 wherein the nuclear plant is a single nuclear plant of a group of nuclear plants consisting of: gas-cooled nuclear plants, liquid-metal-cooled nuclear plants, and heavy-water-cooled nuclear plants.
11. The system as in claim 1 wherein the at least one radiation detector is at least one scintillator detector.
12. The system as in claim 11 wherein the at least one scintillator detector is a sodium-iodide detector comprising a NaI scintillator.
13. The system as in claim 11 wherein each of the at least one scintillator detector includes a photomultiplier tube and a preamplifier.
14. The system as in claim 11 wherein each of the at least one scintillator detector includes a single photomultiplier for detecting light photons.
15. The system as in claim 1 wherein the at least one radiation detector is a bismuth-germanate-oxide (BGO) detector.
16. The system as in claim 1 wherein the at least one radiation-monitoring hodoscope unit is a plurality of such hodoscope units mounted external to the pressure vessel and adapted to function as plant-operation-monitoring instruments, as well as a real-time monitoring function of a shutdown nuclear plant, as well as monitoring such a plant while undergoing damaging or potentially damaging transients.
17. The system as in claim 16, wherein the damaging or potentially damaging transient includes one of a group of transients consisting of an accidental or uncontrolled loss-of-coolant condition, including melting of the reactor fuel, and melt-through of nuclear fuel through the bottom of the pressure vessel.
18. The system as in claim 16 wherein a biological shield surrounds the pressure vessel and at least a portion of the plurality of hodoscope units are mounted in or within the biological shield and pointed toward the pressure vessel so as to monitor gamma radiation produced within the pressure vessel.
19. The system as in claim 18 wherein the at least one hodoscope unit mounted within the biological shield is pointed to a region below the pressure vessel so as to monitor radiation originating in the region below the pressure vessel.
20. The system as in claim 18 wherein the at least one hodoscope unit is pointed to the region below the pressure vessel.
21. The system as in claim 16 wherein data obtained from at least some of the hodoscopes units is stored for later analysis.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A process for recovering phenol comprising the steps of:
(A) contacting a first waste stream from a BPA production process and a second waste stream from a phenolacetone production process with a hydrocarbon stream,
wherein said first waste stream and said second waste stream comprise phenol, and wherein at least a portion of said phenol from said first waste stream andor from said second waste stream is transferred into said hydrocarbon stream; then
(B) separating said hydrocarbon stream after contacting step (A) from said waste streams; and
(C) recovering said phenol from said hydrocarbon stream from step (B).
2. The process of claim 1, wherein said hydrocarbon stream is substantially immiscible with said waste streams.
3. The process of claim 2, wherein said first aqueous waste stream from a BPA process having volatile sulfur compounds and phenol is stripped to remove at least a portion of said volatile sulfur compounds from said aqueous waste stream prior to contacting with said hydrocarbon stream.
4. The process of claim 1, wherein said hydrocarbon comprises cumene, toluene, a mixture of cumene and alpha methyl styrene (AMS), ethers, methyl tert-butyl ether, ethyl tert-amyl ether, diisopropyl ether, ketones, methyl ethyl ketone, methyl isobutyl ketone, acetate esters, propyl acetate, butyl acetate, amyl acetate, hexyl acetate, or any combination thereof.
5. A process for recovering phenol comprising the steps of:
(A) contacting a first waste stream comprising water and phenol from a BPA process and a crude product stream comprising phenol and acetone produced by a phenolacetone production process,
(B) separating at least a majority of said phenol and acetone from said first waste stream and said crude product stream to form a phenolacetone product stream and a second waste stream having less than 5 wt % of phenol; and
(C) recovering substantially all the phenol from said second waste stream by extraction, distillation, absorption, or a combination thereof, to produce an aqueous stream substantially free of phenol.
6. The process of claim 5, further comprises recycling at least a portion of said second waste stream to step (A).
7. The process of claim 6, wherein said first waste stream comprises volatile sulfur compounds and said first waste stream is subjected to stripping prior to step (A).
8. The process of claim 7, wherein said first waste stream comprises at least 5 wt % phenol based on the total weight of said first waste stream.
9. A process for producing BPA comprising the steps of:
(a) recovering phenol and acetone from a crude product stream comprising phenol and acetone produced by a phenolacetone production process, which also produces an aqueous waste stream comprising water, unrecovered phenol and other reaction byproducts;
(b) reacting acetone with a stoichiometric excess of phenol in the presence of an acidic catalyst, possibly in the presence of a cocatalyst or promoter either homogeneously fed or heterogeneously bound to an acidic catalyst, to form a reaction product stream comprising crude BPA product, unreacted phenol, possibly unreacted acetone, possibly cocatalyst or promoter, water of condensation, and other reaction byproducts;
(c) distilling in single or multistage the reaction product stream from step (b) to distill off a first stream comprising water, a portion of unreacted phenol, possibly unreacted acetone, possibly cocatalyst or promoter or derivatives thereof if present in step (b), and other reaction byproducts, which constitutes the BPA waste stream, and a second stream having a portion of unreacted phenol; while sending downstream to a BPA purification step, the purification step comprising one or more solid-liquid separation and wash steps, the resulting concentrated BPA phenolic feed stream consisting essentially of phenol in which the BPA and byproducts have been concentrated;
(d) producing purified BPA by crystallization of the concentrated BPA phenolic feed stream of step (c); and
(e) separating the purified BPA crystals of step (d) by solid-liquid separation and washing same in one or multiple stages with a wash stream which may include at least a portion of the second stream, or spent wash or mother liquor from subsequent crystallization, solid-liquid separation, and wash steps, to produce a final washed BPA-phenol adduct, a final spent wash and a final mother liquor;
(f1) recovering phenol and possibly acetone from a BPA waste stream having the first stream by the steps of:
(1) stripping any volatile sulfur compounds from the BPA waste stream;
(2a) contacting the stripped BPA waste stream with an immiscible hydrocarbon stream, wherein the immiscible hydrocarbon stream comprises at least one of cumene, phenol, acetone, and alpha-methylstyrene (AMS); or
(2b) after combining the stripped BPA waste stream with a phenol waste stream having a portion of the aqueous waste stream from step (a), contacting the combined stream with an immiscible hydrocarbon stream to recover a portion of the phenol in the stripped BPA waste stream or the combined stream into the immiscible hydrocarbon stream, wherein said immiscible hydrocarbon stream comprises at least one of cumene, phenol, acetone, and alpha-methylstyrene (AMS); then
(3) separating the phenol depleted stripped BPA waste stream, or the phenol depleted combined stream, as an aqueous stream from the immiscible hydrocarbon stream; and
(4) further recovering substantially all the phenol and acetone from the aqueous stream from step (3) by extraction, distillation, absorption, or a combination thereof, to produce an aqueous stream substantially free of phenol; or
(f2) recovering phenol and possibly acetone from phenolBPA waste stream(s) having the aqueous waste stream from step (a) and the first stream from step (c) by the steps of:
(1) stripping any volatile sulfur compounds from the first stream from step (c);
(2) combining the waste streams from steps (1) and (a) to form a combined waste stream; and
(3) recovering substantially all the phenol and acetone from the combined waste stream from step (2) by extraction, distillation, absorption, or a combination thereof, to produce an aqueous stream substantially free of phenol; and
(g) recovering and recycling the recovered phenol andor acetone product of step
(f1) or (f2) to steps (a) andor (b).
10. The process of claim 9 wherein the phenolacetone production process of step (a) comprises an upstream phenolacetone plant or an upstream hydroperoxide cleavage process step.
11. The process of claim 9 wherein the combined waste stream from step (2) of step (f2) is distilled to recover at least a portion of acetone prior to substantial recovery of phenol in step (3).
12. A process for producing BPA comprising:
(1) contacting benzene and a C3 alkylating agent under alkylation conditions with an alkylation catalyst in a reaction zone to produce an alkylation effluent comprising cumene;
(2) oxidizing the cumene from step (1) to produce the cumene hydroperoxide;
(3) cleaving the cumene hydroperoxide from step (2) to produce a crude product stream comprising phenol, acetone, water, unreacted cumene and other reaction byproducts,
(4) processing the crude product stream from step (3) to recover phenol and acetone, and to produce a waste stream comprising water, unrecovered phenol, unrecovered acetone and other reaction byproducts;
(5) reacting acetone with a stoichiometric excess of phenol in the presence of an acidic catalyst, possibly in the presence of a cocatalyst or promoter either homogeneously fed or heterogeneously bound to an acidic catalyst, to form a reaction product stream comprising crude BPA product, unreacted phenol, possibly unreacted acetone, possibly cocatalyst or promoter, water of condensation, and other reaction byproducts;
(6) distilling in single or multistage the reaction product stream from step (5) to distill off a first stream comprising water, a portion of unreacted phenol, possibly unreacted acetone, possibly cocatalyst or promoter or derivatives thereof if present in step (5), and other reaction byproducts, which comprises at least a portion of the BPA waste stream, and a second stream having a portion of unreacted phenol; while sending downstream to a BPA purification step, the purification step comprising one or more solid-liquid separation and wash steps, the resulting concentrated BPA phenolic feed stream consisting essentially of phenol in which the BPA and byproducts have been concentrated;
(7) producing purified BPA by crystallization of the concentrated BPA phenolic feed stream of step (6); and
(8) separating the purified BPA crystals of step (7) by solid-liquid separation and washing same in one or multiple stages with a wash stream which may include at least a portion of the second stream, or spent wash or mother liquor from subsequent crystallization, solid-liquid separation, and wash steps, to produce a final washed BPA-phenol adduct, a final spent wash and a final mother liquor;
(9a) recovering phenol and possibly acetone from a BPA waste stream having the first stream of step (6) by the steps of:
(i) stripping any volatile sulfur compounds from the BPA waste stream,
(ii) contacting the stripped BPA waste stream with an immiscible hydrocarbon stream, or after combining the stripped BPA waste stream with a phenol waste stream having a portion of the aqueous waste stream from step (4), contacting the combined stream with an immiscible hydrocarbon stream to recover a portion of the phenol in the stripped BPA waste stream or the combined stream from (i) into the immiscible hydrocarbon stream, wherein the immiscible hydrocarbon stream comprises at least one of cumene, phenol, acetone, and alpha-methylstyrene (AMS); then
(iii) separating the phenol depleted stripped BPA waste stream, or the phenol depleted combined stream, as an aqueous stream from the immiscible hydrocarbon stream; and
(iv) further recovering substantially all the phenol and acetone from the aqueous stream from step (iii) by extraction, distillation, absorption, or a combination thereof, to produce an aqueous stream substantially free of phenol; or
(9b) recovering phenol and possibly acetone from phenolBPA waste stream(s) having the waste stream from step (4) and the first stream from step (6) by the steps of:
(i) stripping any volatile sulfur compounds from the first stream from step (6);
(ii) combining the stripped first streams from steps (i) and waste stream from (4) to form a combined waste stream;
(iii) recovering substantially all the phenol and acetone from the combined waste stream from step (ii) by extraction, distillation, absorption, or a combination thereof, to produce an aqueous stream substantially free of phenol; and
(10) recovering and feeding the recovered phenol and acetone product of step (9a) or (9b) to steps (4) andor (5).
13. The process of claim 12 wherein said C3 alkylating agent comprises an aliphatic or aromatic organic compound having one of more available alkylating aliphatic groups of 3 carbon atoms, or mixtures thereof.
14. The process of claim 12 wherein the alkylation catalyst in step (1) comprises a molecular sieve selected from the group consisting of zeolite Beta, faujasite, mordenite, MCM-22, PSH-3, SSZ-25, ERB-1, ITQ-1, ITQ-2, ITQ-30, MCM-36, MCM-49, MCM-56 and mixtures thereof.
15. The process of claim 12 wherein said alkylation effluent produced in step (1) comprises polyisopropylbenzenes and the process further comprises contacting said polyisopropylbenzenes with benzene in the presence of a transalkylation catalyst to produce cumene.
16. The process of claim 12 wherein said oxidizing step (2) is conducted in the presence of an oxidation catalyst.
17. The process of claim 12 wherein the cleaving step (3) is conducted in the presence of a catalyst.
18. The process of claim 12 wherein step (5) is conducted in the presence of added promoter selected from the group consisting of methyl mercaptan, ethyl mercaptan, 2,2-bis(methylthio)propane, mercaptocarboxylic acid, and promoter-bound resins.
19. The process of claim 12 wherein at least one of the steps (1), (2) or (3) is effected by catalytic distillation.
20. The process of claim 12 wherein the combined waste stream from step (ii) in step (9b) is distilled to recover at least a portion of acetone prior to substantial recovery of phenol in step (iii).
21. A process for producing BPA comprising a BPA production process step of reacting acetone with a stoichiometric excess of phenol under acidic conditions, possibly in the presence of a cocatalyst or promoter, to form a reaction product stream comprising crude BPA product wherein a portion of the phenol, and possibly acetone, comprises recycle recovered from waste water streams generated by an upstream phenolacetone production process and the BPA production process step.
22. The process of claim 21 wherein the upstream phenolacetone production process comprises an upstream cumene hydroperoxide cleavage process step.