Biodegradation of chlorinated compounds

1
Biodegradation of chlorinated compounds

• ?first-order decay(Cornuet et al.,2000)

rfirst order rate coefficient?yyield? kfirst
order decay coefficient?Cconcentration in
groundwate? y10.79?y20.74?y30.64?y40.45
2
Transport of VOCs in groundwater

• ?governing equations with considering advection,
  dispersion, adsorption and biodegradation(Cornuet
  et al.,2000)

Rretardation factor?Dx?Dy?DzDispersion
coefficient on x,y,z direction vsgroundwater
velocity
3
Site summary and Injection wells
4
Calculating injection amount

• ?Design soft of Regenesis
• Historical highest VOC concentrations of well
  GW6 were used
• Other items were analyzed from GW6 samples
  before designing

Requested minimum HRC amount 218kg(reduction of
sulfate 110mg/l) 116kg(reduction of sulfate
50mg/l)
5
HRC Injection
?
?
?
After warmed with 60? water, injected with
a pump(Injected amount 272kg) ?warmed
?stiring ?injection process ??after injection
?
?
6
VOCs concentrations after HRC injection

• ?concentrations of PCE?TCE decreased(decreasing
  ratios 97.5?89.2)
• ?concentrations of DCE?VC increased firstly and
  then turned to desreasing

Bioremediation process is accelerated by injected
HRC
7
Monitored water quality (sulfate etc.)

• ?6776mg/l H from HRC was used to decrease
  sulfate
• ?By HRC injection
• pH?ORP are decreased
• EC?TOC are increased
• ?DO should be decreased,
• however the result of 107 day
• shows increasing trend.
• Reason is not clear at the moment

8
Monitored water quality (organic acids)

• ? Pyruvic acid and acetic acid in well GW6
  showed increasing trend

H was released by breakdown of Lactic acid
GW6
9
Enhanced bioremediation estimation with BIOCHLOR

• Before HRC Injection (natural condition)
• ?upon monitoring well data(MW6U?GW6)

After HRC injection (107 days) ?MW6U?GW6
10
Estimated half life with BIOCHLOR

• HRC??????107????????????
• ?????????????PCE367??TCE119??
• cis-1,2-DCE4.5??????????????
• ?GW6?VOCs?????????
• ????????????????????????
• ????DCE?????????????????