1、Designation: F 1524 95 (Reapproved 2001)Standard Guide forUse of Advanced Oxidation Process for the Mitigation ofChemical Spills1This standard is issued under the fixed designation F 1524; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revi
2、sion, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide covers the considerations for advancedoxidation processes (AOPs) in the mitigation of sp
3、illed chemi-cals and hydrocarbons dissolved into ground and surfacewaters.1.2 This guide addresses the application of advanced oxi-dation alone or in conjunction with other technologies.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is th
4、eresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. In addition, it is theresponsibility of the user to ensure that such activity takesplace under the control and direction of a qu
5、alified person withfull knowledge of any potential safety and health protocols.2. Terminology2.1 Definitions of Terms Specific to This Standard:2.1.1 advanced oxidation processes (AOPs)ambient tem-perature processes that involve the generation of highly reac-tive radical species and lead to the oxid
6、ation of waterbornecontaminants (usually organic) in surface and ground waters.2.1.2 inorganic foulantscompounds, such as iron, calciumand manganese, that precipitate throughout a treatment unitand cause reduced efficiency by fouling the quartz sleeve thatprotects the lamp in photolytic oxidation AO
7、P systems or thefibreglass mesh that is coated with TiO2in photocatalytic AOPsystems.2.1.3 mineralizationthe complete oxidation of an organiccompound to carbon dioxide, water, and acid compounds, thatis, hydrochloric acid if the compound is chlorinated.2.1.4 photoreactorthe core of the photoreactor
8、is a UVlamp that emits light in the broad range of 200 to 400 nmwavelength range.2.1.5 radical speciesa powerful oxidizing agent, princi-pally the hydroxyl radical, that reacts rapidly with virtually allorganic compounds to oxidize and eventually lead to theircomplete mineralization.2.1.6 scavengers
9、a term used for substances that reactwith hydroxyl radicals that do not yield species that propagatethe chain reaction for contaminant destruction. Scavengers canbe either organic or inorganic compounds.3. Significance and Use3.1 GeneralThis guide contains information regarding theuse of AOPs to oxi
10、dize and eventually mineralize hazardousmaterials that have entered surface and groundwater as theresult of a spill. Since much of this technology development isstill at the benchscale level, these guidelines will only refer tothose units that are currently applied at a field scale level.3.2 Oxidizi
11、ng Agents:3.2.1 Hydroxyl Radical (OH)The OH radical is the mostcommon oxidizing agent employed by this technology due toits powerful oxidizing ability. When compared to other oxi-dants such as molecular ozone, hydrogen peroxide, or hy-pochlorite, its rate of attack is commonly much faster. In fact,i
12、t is typically one million (106) to one billion (109) times fasterthan the corresponding attack with molecular ozone (1).2Thethree most common methods for generating the hydroxylradical are described in the following equations:H2O21 hv 2OH (1)2O31 H2O2 2OH 1 3O2(2)Fe121 H2O2 OHFe131 OH2Fentons React
13、ion! (3)3.2.1.1 Hydrogen peroxide is the preferred oxidant forphotolytic oxidation systems since ozone will encourage the airstripping of solutions containing volatile organics (2). Capitaland operating costs are also taken into account when a decisionon the choice of oxidant is made.3.2.1.2 Advance
14、d oxidation technology has also been devel-oped based on the anatase form of titanium dioxide. This1This guide is under the jurisdiction of ASTM Committee F20 on HazardousSubstances and Oil Spill Response and is the direct responsibility of SubcommitteeF20.22 on Mitigation Actions.Current edition ap
15、proved May 15, 1995. Published July 1995. Originallypublished as F 1524 94. Last previous edition F 1524 94.2The boldface numbers in parentheses refer to the list of references at the end ofthis standard.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2
16、959, United States.method by which the photocatalytic process generates hy-droxyl radicals is described in the following equations:TiO21 hv 1 H2O OH 1 H11 e2(4)2e21 2O21 2H2O 2OH 1 O21 2OH2(5)3.2.2 PhotolysisDestruction pathways, besides the hy-droxyl radical attack, are very important for the more
17、refrac-tory compounds such as chloroform, carbon tetrachloride,trichloroethane, and other chlorinated methane or ethane com-pounds. A photoreactors ability to destroy these compoundsphotochemically will depend on its output level at specificwavelengths. Since most of these lamps are proprietary,prel
18、iminary benchscale testing becomes crucial when dealingwith these compounds.3.3 AOP Treatment Techniques:3.3.1 Advanced oxidation processes (AOPs) may be appliedalone or in conjunction with other treatment techniques asfollows:3.3.1.1 Following a pretreatment step. The pretreatmentprocess can be eit
19、her a physical or chemical process for theremoval of inorganic or organic scavengers from the contami-nated stream prior to AOP destruction.3.3.1.2 Following a preconcentration step. Due to the in-crease in likelihood of radical or molecule contact, very dilutesolutions can be treated cost effective
20、ly using AOPs after beingconcentrated.3.4 AOP Treatment ApplicationsAdvanced oxidation pro-cesses (AOPs) are most cost effective for those waste streamscontaining organic compounds at concentrations below 1 %(10 000 ppm). This figure will vary depending upon the natureof the compounds and whether th
21、ere is competition for theoxidizing agent.4. Constraints on Usage4.1 GeneralAlthough AOPs are destruction processes, inorder for compound mineralization to take place, the oxidationreactions must be taken to completion. In most cases, effluentanalysis is the only method available to ensure this stat
22、e. Somecompounds are selective in their reactivity. For these reasons,preliminary bench-scale testing and literature searches on thepredicted reaction mechanisms are essential prior to full scaletreatment.4.2 Presence of ScavengersScavengers, such as bicarbon-ate and carbonate, will adversely affect
23、 the ability of theoxidizing agent to react with the target compounds if thesecompounds are left as ions within the solution. Adjusting thepH of the solution will reduce this problem, however, theadditional cost requirements must be balanced against thebenefit received.4.3 Contaminant Identification
24、The types of contaminantsand their corresponding destruction rate constants will affectthe overall system performance. In general, chlorinated aliphat-ics with carbon-to-carbon double bonds (unsaturated), degrademore quickly than chlorinated compounds with single bonds(saturated). In addition, refra
25、ctory compounds such as carbontetrachloride, chloroform, and other chlorinated methane com-pounds are quite resistant to degradation in the presence of thehydroxyl radical and should be destroyed photochemically(that is, UV alone).4.4 pH AdjustmentAdjusting the pH of the solution priorto treatment m
26、ay significantly affect the performance of thetreatment. A feed solution at a pH of 9 will tend to causeprecipitation of most inorganics, while a pH of 5 will causethem to remain in solution throughout the treatment process. Insituations where the inorganics are in a relatively low concen-tration (l
27、ow parts per million), one would tend to lower the pH,while a higher pH would be preferable at the higher concen-trations where the inorganics could be separated and removed.4.5 System FoulingGenerally, inorganic foulants, such asiron, manganese, and calcium, in the ppm range, cause reducedflow, inc
28、reased pressure and low performance of a treatmentsystem. This phenomenon is common in most organic treat-ment units regardless of the mechanism employed. Pretreat-ment systems usually involve chemical addition (that is, pHadjustment) or membrane technology, or both, as they aregenerally the most ec
29、onomical and effective for inorganicremoval. Preliminary benchscale testing is commonly used todetermine the applicability and the cost-effectiveness of thedifferent pretreatment systems.4.6 Off-Gas AnalysisOrganic analysis of the exiting gas-eous stream will assist the operator in modifying systemp
30、arameters to maximize system performance and efficiency.This technique is also beneficial during preliminary testing asit provides an indication of the AOP technologys ability todestroy the compounds as compared to simply stripping themfrom the water phase into the air.4.7 Destruction Rate Constants
31、The reaction of the OHradical with organic compounds is largely dependent upon therate constant. A list (3) of reaction rates for common contami-nants is shown in Table 1.5. Practical Applications5.1 Emergency SituationsAdvanced oxidation process(AOP) applications would normally follow containment a
32、ndrecovery of the waste stream in question. The time required forthis primary stage should be sufficient for the AOP user to atleast obtain the necessary background information on thecontaminants in question. Benchscale confirmation testing isdesirable, if time permits. Under no circumstances should
33、 AOPbe used in a clean-up unless the manufacturer can supply dataconcerning testing on the same or similar chemical solutions.TABLE 1 Rate Constants for the Hydroxyl RadicalCompound, m kM, OH, (10+9m1s1)Benzene 7.8Hydroperoxide Ion 7.5Vinyl Chloride 7.1Chlorobenzene 4.51-Butanol 4.2Trichloroethane 4
34、.0Nitrobenzene 3.9Pyridine 3.8Toluene 3.0Tetrachloroethane 2.3Carbonate Ion 0.39Dichloromethane 0.058Bicarbonate 0.0085Chloroform ;0.005Carbon Tetrachloride NRF 1524 95 (2001)25.1.1 Emergency Clean-Up OperationFor a spill, underemergency clean-up situations, the AOP technology user mustdo the follow
35、ing:5.1.1.1 Monitor the feed, effluent, and off-gas stream analy-sis closely,5.1.1.2 Monitor the feed flowrate and adjust accordingly,5.1.1.3 Use holding tanks prior to discharge in order tobuffer changes in discharge concentrations, and5.1.1.4 Modify system parameters as necessary, based onthe abov
36、e conditions.5.2 Non-Emergency OperationOnce the leachate orchemicals reach the groundwater, the critical period is over andrapid response is less effective. Preliminary testing and prepa-ration can be performed by the mitigator prior to treatment.Pretesting and manufacturers information will determ
37、ine themost appropriate operating conditions and the pretreatmentrequired. This will not, however, reduce the importance ofclosely monitoring all aspects of the data. Sudden changes infeed concentrations could severely reduce the destruction rates.5.3 Field Scale Results Using AOP TechnologyTable 2p
38、rovides a summary of typical destruction capabilitiesachieved during photolytic AOP field trials conducted between19881993.6. Keywords6.1 advanced oxidation; AOP; destruction; enhanced oxida-tion; hydrogen peroxide; hydroxyl radical; ozone; photolysis;titanium dioxide; ultravioletTABLE 2 Typical Fie
39、ld Scale Results of AOP Field TrialsNOTE 1MF microfiltrationRO reverse osmosisSpecific Compound FlowrateConcentrationNotes ReferenceInitial Final1,4 dioxane 19114 L/min 100 ppm 10 ppb system able to reduce dioxane in raw or deionized waterconsistently(1)methylene chloride 19 L/min 130730 ppb 3.1 ppb
40、 high iron conc, prevented (1)trichloroethylene 9.719.9 ppm 0.4 ppb precipitation by maintaining pH at 31,2 trans-dichloroethylene 612.5 ppm 0.1 ppbvinyl chloride 101010 ppb 0.5 ppbchloroethane 10 ppb 0.3 ppbnitrate esters, explosives 15 L/min 10005000 ppm 1 ppm systems tested with UV/H202, UV alone
41、, and proprietarypretreatment for carbonate removal(1)trichloroethylene, 30 L/min 1.55 ppm 5 ppb pH adjustment, (4)benzene, 0.23 ppm 0.8 ppb MF/UV/H202 systemchloroform, 0.08 ppm 0.04 ppmchlorobenzene, 0.05 ppm 1 ppb1,2 dichloroethane 0.01 ppm 2 ppbbenzene, 23 L/min 1.22 ppm 0.05 ppm UV/H202(5)tolue
42、ne, 0.47 ppm 0.05 ppmxylene 9.29 ppm 0.10 ppmethylbenzene 0.59 ppm 0.05 ppmn-nitrosodimethylamine 95 L/min 80 ppt 5 ppt UV (6)cyanide not available 6 ppm 2 ppm sulphide and fluoride (7)precipitated prior to treatmentdichloroethylene, batch, 5 minutes 0.5 ppm ND phenolics pretreated with proprietary
43、reagent (7)dichloroethane 5 ppm NDbenzene 3 ppm 0.009 ppmtrichloroethylene, 26 L/min 30 000 ppb 0.4 ppb adjusted pH 3 to prevent fouling of UV quartz (7)dichloroethylene, 20 000 ppb 0.1 ppbvinyl chloride 500 ppb 0.5 ppbmethylene chloride batch 470 ppb 1 ppb UV/03/H202 at pH 10 (8)benzene 353 ppb 1 p
44、pbtoluene 2740 ppb 4 ppbF 1524 95 (2001)3REFERENCES(1) Keller, L., Reed, D., “Recent Applications of Environment CanadasMobile Enhanced Oxidation Unit,” Air and Waste ManagementAssociation 85th Annual Meeting and Exhibition, 1991.(2) Nyer, E. K., Groundwater Treatment Technology, 2nd Ed., VanNostran
45、d Reinhold, New York, 1992, p. 119.(3) Glaze, W. H., Kang, J., “Chemical Models of Advanced OxidationProcesses,” ProceedingsA Symposium on Advanced Oxidation Pro-cesses for the Treatment of Contaminated Water and Air, 1990.(4) Jacquemot, S., Keller, L., Punt, M., “Comparison of Mobile TreatmentTechn
46、ologies at the Gloucester Landfill,” Internal Report, EmergenciesEngineering Division, Environment Canada, 1991.(5) Ladanowski, C., “Field Scale Demonstration of Technologies forTreating Groundwater at the Gulf Strachan Gas Plant,” CanadianAssociation of Petroleum Producers Publication, April 1993.(
47、6) Cooper, D., and Keller, L., “Advanced Oxidation Technology Dem-onstration at Ohsweken Six Nations Indian Reserve, Proceedings ofthe Tenth Technical Seminar on Chemical Spills,” 1993.(7) Correspondence from Doug Reed, Solarchem Environmental Systems,Nov. 6, 1991.(8) Solarchem Enterprises,“ Leachat
48、e Remediation at the Oswego Super-fund Site Using RayoxA Second Generation Enhanced OxidationProcess,” Final Report to Emergencies Engineering Division, Envi-ronment Canada, 1989.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item me
49、ntionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Head
