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FORMATE BRINES 
DRILL-IN AND COMPLETION FLUIDS SINCE 1993 
John Downs 
Formate Brine Ltd 
www.formatebrine.com
Formate brines 
Sodium 
formate 
Potassium 
formate 
Cesium 
formate 
Solubility in 
water 
47 %wt 77 %wt 83 %wt 
Density ...
LATEST FORMATE SUCCESS – Unconventional 
shale drilling – Formates cut drilling times in half 
Oil companies in Canada are...
Potassium formate brines excelling in Canada 
as solids-free and polymer-free shale drilling fluid 
118 shale wells drille...
New explanation for shale drilling success with 
potassium formate – Osmosis 
Paper to be presented to the 2015 SPE/IADC D...
The traditional use for formate brines is in 
High-Pressure High-Temperature gas wells 
Low-solids heavy fluids for deep H...
42 deep HPHT gas fields developed using formate 
brines , 1995-2011. Now probably > 50 fields * 
Country Fields Reservoir ...
Almost every HPHT gas field in northern North Sea in 
Norway drilled and/or completed in formate brine 
More than 400 well...
Formate brines as packer fluids in USA (GOM) 
OPERATOR LOCATION 
Packer Fluid 
(ppg) 
BHT 
(°C) 
BHT 
(°F) 
Start 
Date 
E...
BP High Island, Gulf of Mexico – Formate 
brine used as a packer fluid for 6 years 
• 177ºC, 14,000 psi 
• S13Cr tubing fa...
The economic benefits provided by formate 
brines in HPHT gas field developments 
Formate brines improve the economics of ...
Formate brines used by OMV in Pakistan in 
2005-6 for drill-in and completions in HPHT gas wells 
12 John Downs - Formate ...
Formate brines used by OMV in Pakistan in 
2005-6 for drill-in and completion in HPHT gas wells 
13 John Downs - Formate B...
www.formatebrines.com 
Source of all the latest formate information 
14 John Downs - Formate Brine Ltd
Useful reference material 
The Formate Technical Manual 
- 26 chapters 
- > 400 pages 
- Available in English, Spanish and...
Another source of formate information 
The Formate Brines group on LinkedIn – www.linkedin.com 
16 John Downs - Formate Br...
And another source of formate information.... 
The Formate Brines newsletter – Issue #9 out this week 
17 John Downs - For...
Formate brines – Discovery and qualification by 
Shell Research 
Shell patent the use 
of formates as 
polymer stabilisers...
Formate Brines – Properties that make them 
excellent drilling and completion fluids 
• Density up to 2.3 g/cm3 and pH 9-1...
Benefits of formate brines – Compatible with 
polymers, so can be used as drilling fluids 
A traditional low-solids format...
Formate brines launched as low-solids drilling 
fluids in mid-1990’s 
John Downs - Formate Brine Ltd 
Property Typical val...
Benefits of formate brines - they raise the 
thermal stability ceiling of polymers 
Bar graph showing the temperature at w...
Benefits of formate brines - ROP enhancement 
Low-solids formate brines increase drilling ROP by >100% 
compared to OBM (i...
Benefits of formate brines - ROP enhancement 
Zero-solids formate brines can increase drilling ROP by 200-300% vs 
WBM 
Ze...
Benefits of formate brines - ROP enhancement 
Ramsey et al found correlation between Fann 600 reading of drilling 
fluids ...
Benefits of formate brines – Zero/low solids 
gives better hydraulics 
• Lower Surge and Swab Pressures 
- Faster tripping...
Benefits of formate brines – Natural lubricity 
Steel-steel coefficient of friction in potassium formate brine (BP test) 
...
Benefits of formate brines – Low methane 
solubility 
• Low methane solubility and diffusion rates 
- Easier kick detectio...
Finnish Environment Institute recommends the use of 
potassium formate in sensitive groundwater areas 
29 John Downs - For...
Extracts from summary of Finnish Environment 
Institute report on potassium formate 
“Potassium formate is already widely ...
Extracts from abstracts of Finnish Environment 
Institute reports on potassium formate 
Alternative deicing agents and gro...
Formate brines – Production and first field use 
- Milestones 
First field use of 
sodium formate: 
Shell drills and 
comp...
Potassium formate brine has been used to drill 
deep HPHT gas wells since 1995 
First use : ExxonMobil’s Walsrode field, o...
Potassium formate from Addcon used in 15 deep 
HPHT gas well constructions in Germany ,1995-99 
Fluids service provided by...
Summary of potassium formate brine use in 
HPHT gas wells in Germany,1995-99 
35 John Downs - Formate Brine Ltd
Addcon’s potassium formate plant in Norway has 
been supplying the oil industry since 1994 
Production Site 
ADDCON NORDIC...
Potassium formate production by Addcon 
• The first and largest producer of potassium formate 
- Brine production capacity...
Addcon’s new potassium formate plant in 
Bitterfeld, Germany 
Only 7 hours drive from Bitterfeld to Vienna area 
38 John D...
Potassium formate brine – Methods of shipment 
39 John Downs - Formate Brine Ltd
Typical potassium brine grades 
% w/w Density TCT* 
SG oC 
75 1.57 7 
71 1.53 2 
63 1.46 -13 
* Crystals of potassium form...
Formate brines – Some important milestones : 
1999-2004 
First 
production of 
non-caking 
crystalline K 
formate by 
Addc...
Cesium formate produced by Cabot in Canada 
from pollucite ore 
Pollucite ore 
Cs0.7Na0.2Rb0.04Al0.9Si2.1O6·(H20) 
• Mined...
The first sustained use of K/Cs formate brine was in 
the world’s largest HPHT gas field development 
Elgin/Franklin field...
Formate brines – Some published milestones 
2005 -2010 
OMV 
Pakistan 
start using K 
formate to 
drill and 
complete 
(wi...
Saudi Aramco have been drilling HPHT gas wells 
with potassium formate brine since 2003 
45 John Downs - Formate Brine Ltd
Saudi Aramco use of formate brines, 2003-2009 
• 7 deep gas fields 
• 44 HPHT wells drilled 
• 70,000 ft of reservoir 
dri...
Summary from Aramco’s OTC paper 19801 
Aramco consume around 300 m3/month of K formate brine 
47 John Downs - Formate Brin...
Potassium formate brine weighted with Micromax® 
in Kuwait and Saudi Arabia 
Good results in first 9 HPHT wells – 
could b...
Potassium formate brine weighted with Micromax for 
drilling deep HPHT fractured carbonate wells 
10,000 psi, 140oC, H2S =...
Potassium formate brine weighted with Micromax for 
drilling deep HPHT fractured carbonate wells 
“The results were extrao...
Pakistan - OMV use potassium formate brine for 
HPHT deep gas well drilling and completions 
51 John Downs - Formate Brine...
Extracts from OMV’s SPE papers and SPE 
presentations – note 1,700 psi overbalance, and 350oF 
52 John Downs - Formate Bri...
OMV drills and completes using ESS in 
potassium formate brine – Pakistan, 2006/7 
53 John Downs - Formate Brine Ltd
Norway, 2002 - Perforating in solids-free oil-based 
kill pill weighted with formate brine 
• Visund field 
- BHST: 118o C...
Perforating Visund wells in solids-free oil-based 
kill pill weighted with formate brine 
• Visund – Change to formate kil...
Formate brines used as HPHT cased well 
completion fluids after drilling with OBM 
Formate brines have been used as (perfo...
Managed Pressure Drilling and completion of 
fractured carbonates with formate brine 
SPE 165761 (2012) “ Experience with ...
Kanowit SS-1 : Production profile from start-up - natural clean-up 
– no stimulation . Carbonate reservoir 
• 100 MMscfd g...
Kanowit SS-1 : Multi-rate well test results from carbonate 
Both wells can produce > 150 MMscfd gas and > 6,000 bpd conden...
North Sea - Formate brines used as combined 
HPHT drill-in and completion fluids 
33 development* wells drilled and comple...
Tune field – HP/HT gas condensate reservoir drilled 
and completed with K formate brine, 2002 
4 wells : 350-900 m horizon...
Tune wells - Initial Clean-up – Operator’s view 
(direct copy of slide) June 2003 
• Wells left for 6-12 months before cle...
Tune – Production of recoverable gas and condensate 
reserves since 2003 (NPD data) 
Good early production from the 4 well...
Huldra field – HPHT gas condensate reservoir 
drilled and completed with formate brine, 2001 
• 6 production wells 
• 1-2 ...
Comments from Huldra project manager 
65 
TROND JUSTAD 
Manager-Huldra Project 
Bergen, Norway 
“CESIUM FORMATE HAS PLAYED...
Huldra – Production of recoverable gas and 
condensate reserves since Nov 2001 (NPD data) 
Plateau production from first 3...
Kvitebjørn field – HPHT gas condensate reservoir drilled 
and completed with K/Cs formate brine, 2004-2013 
• 13 wells to ...
A few of the highlights from Kvitebjoern 
Fast completions and high well productivity 
Kvitebjoern 
well 
Completion 
time...
Kvitebjørn– Production of recoverable gas and 
condensate reserves since Oct 2004 (NPD data) 
Good production reported fro...
Economic benefits of using formate brines 
• SPE 130376 (2010): “A Review of the Impact of the Use of Formate Brines 
on t...
Economic benefits from using formate brines 
- Latest paper 
71 John Downs - Formate Brine Ltd
Economic benefits from using formate brines 
- Good well performance and recovery of reserves 
• “High production rates wi...
Economic benefits from using formate brines 
- More efficient and safer drilling 
Better/safer drilling environment saves ...
Formate Brines : Allow fast solids-free drilling 
Solids-free formate brines drill deep horizontal well sections much 
fas...
Economic benefits from using formate brines 
- Improved well control and safety 
• Elimination of barite and its sagging p...
Economic benefits from using formate brines 
- More efficient/faster completions 
- Drill-in and completing with 
formate ...
Economic benefits from using formate brines 
• No differential sticking 
• Pipe and casing running speeds are fast 
• Mud ...
Economic benefits from using formate brines 
- Good reservoir definition if Cs present in fluid 
• High density filtrate a...
Economic benefits from using formate brines 
- Good reservoir imaging 
• Highly conductive fluid 
• Clear resistivity imag...
Formate brines – Summary of economic 
benefits provided to users 
Formate brines improve oil and gas field development 
ec...
Formate brines enable open-hole screen 
completions in high-angle HPHT wells 
Formate brines are low-solids drill-in and c...
Finnish Environment Institute recommends the use of 
potassium formate in sensitive groundwater areas 
Environ Sci Technol...
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Formate Brines - Reservoir drilling and well completion fluids since 1993

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Formate brines as reservoir drilling and well completion fluids since 1993. Presentation made to OMV in Vienna in September 2014.

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  • John - There is a plan to use 17.2ppg Potassium Formate/Micromax as a drilling fluid in Iraq - Are there special recommendation to avoid/minimize the LGS to build up in the Potassium Foramet/Micromax mud? What are the best recommnedation for the shaker screens and the centrifuge. Planned flow rate will be 700-850 gpm.
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  • Tom - Its just a normal NADF to brine displacement procedure, as detailed in the Fluids Management Chapter C1 of the Formate Technical Manual = NADF base oil to WBM with surfactant to water-based mud to formate brine with surfactant to formate brine. Or, if I had my way, you could do it in one step with formate-weighted NMP (n-methyl pyrrolidone)
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  • John - am helping Stratum with a project in Romania and we are going to displace NADF with potassium formate as a drill-in fluid. Is there any special precautions that need to be taken during the displacement other than what is published? Thanks
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  • Hi Bob - I am really pleased that WZ have got you managing their first field trial of the potassium formate Micromax fluid. They have got the best man for the job ! I'm sorry I missed you in Abu Dhabi - i think you were teaching in China at the time. Maybe see you at a wash-up meeting at the end of the job, if Tony/Robin hold it somewhere outside of Iraq ?
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  • Thanks for sharing these with us John. Sorry did not get to AbuDabi with Tony. presently working on this WZ system as you know. Tite hole for the moment.
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Formate Brines - Reservoir drilling and well completion fluids since 1993

  1. 1. FORMATE BRINES DRILL-IN AND COMPLETION FLUIDS SINCE 1993 John Downs Formate Brine Ltd www.formatebrine.com
  2. 2. Formate brines Sodium formate Potassium formate Cesium formate Solubility in water 47 %wt 77 %wt 83 %wt Density 1.33 g/cm3 11.1 lb/gal 1.59 g/cm3 13.2 lb/gal 2.30 g/cm3 19.2 lb/gal Formates are also soluble in some non-aqueous solvents 2 John Downs - Formate Brine Ltd
  3. 3. LATEST FORMATE SUCCESS – Unconventional shale drilling – Formates cut drilling times in half Oil companies in Canada are exploiting a discovery from 1996 – formates are VERY fast in shale vs weighted muds 3 John Downs - Formate Brine Ltd
  4. 4. Potassium formate brines excelling in Canada as solids-free and polymer-free shale drilling fluid 118 shale wells drilled with DMK’s potassium formate drilling fluid since mid-2013 Quote from Encana : “ The fluid is inhibitive, after drilling caliper logs displayed the same response as invert (oil) drilled caliper logs. The ROP improvement has allowed us to cut our lateral drilling time in half! “ 4 John Downs - Formate Brine Ltd
  5. 5. New explanation for shale drilling success with potassium formate – Osmosis Paper to be presented to the 2015 SPE/IADC Drilling conference : ROP Enhancement in Shales through Osmotic Processes Eric van Oort, SPE, and Muneeb Ahmad, The University of Texas at Austin, and Reed Spencer, SPE, Baker Hughes “It will be shown that the mechanism responsible for the Deeptrek ROP results with formate mud is chemical osmosis …..” Potassium formate brine use in unconventional shale drilling may become widespread 5 John Downs - Formate Brine Ltd
  6. 6. The traditional use for formate brines is in High-Pressure High-Temperature gas wells Low-solids heavy fluids for deep HPHT gas well constructions • Reservoir drill-in • Completion • Workover • Packer fluids • Well suspension • Fracking Used in hundreds of HPHT wells since 1995, including some of Europe’s deepest, hottest and highly-pressured gas reservoirs 6 John Downs - Formate Brine Ltd
  7. 7. 42 deep HPHT gas fields developed using formate brines , 1995-2011. Now probably > 50 fields * Country Fields Reservoir Description Matrix type Depth, TVD (metres) Permeability (mD) Temperature (oC) Germany Walsrode,Sohlingen Voelkersen, Idsingen, Kalle, Weissenmoor, Simonswolde Sandstone 4,450-6,500 0.1-150 150-165 Hungary Mako , Vetyem Sandstone 5,692 - 235 Kazakhstan Kashagan Carbonate 4,595-5,088 - 100 Norway Huldra ,Njord Kristin,Kvitebjoern Tune, Valemon Victoria, Morvin, Vega, Asgard Sandstone 4,090-7,380 50-1,000 121-200 Pakistan Miano, Sawan Sandstone 3,400 10-5,000 175 Saudi Arabia Andar,Shedgum Uthmaniyah Hawiyah,Haradh Tinat, Midrikah Sandstone and carbonate 3,963-4,572 0.1-40 132-154 UK Braemar,Devenick Dunbar,Elgin Franklin,Glenelg Judy, Jura, Kessog Rhum, Shearwater West Franklin Sandstone 4,500-7,353 0.01-1,000 123-207 USA High Island Sandstone 4,833 - 177 * More HPHT fields developed in Kuwait, India and Malaysia during 2012-2013 7 John Downs - Formate Brine Ltd
  8. 8. Almost every HPHT gas field in northern North Sea in Norway drilled and/or completed in formate brine More than 400 well construction jobs in Europe with high density formate brines since 1995 8 John Downs - Formate Brine Ltd
  9. 9. Formate brines as packer fluids in USA (GOM) OPERATOR LOCATION Packer Fluid (ppg) BHT (°C) BHT (°F) Start Date End Date Comments Devon WC 165 A-7 8.6 KFo 149 300 1/2005 Devon WC 165 A-8 8.6 KFo 149 300 1/2006 Devon WC 575 A-3 ST2 9.5 KFo 132 270 5/2005 WOG/Devon MO 862 #1 12.0 NaKFo 215 420 4/2005 5/2006 Well P&A – H2O production – G-3 in excellent condition BP/Apache HI A-5 #1 11.5 NaKFo 164 350 2/2002 4/2008 Well P&A - Natural depletion – S13Cr in excellent condition ExxonMobil MO 822 #7 12.0 NaKFo 215 420 2001 EPL ST 42 #1 11.5 NaKFo 133 272 2006 EPL ST 41 #F1 13.0 NaKFo 105 222 2006 EPL EC 109 A-5 11.5 NaKFo 121 250 2006 EPL ST 42 #2 12.8 NaKFo 132 270 2006 Dominion WC 72 #3 BP1 10.0 NaFo 121 250 2006 EPL WC 98 A-3 ST1 12.7 NaKFo 153 307 2006 EPL WC 98 A-3 10.8 NaKFo 154 310 2007 9 John Downs - Formate Brine Ltd
  10. 10. BP High Island, Gulf of Mexico – Formate brine used as a packer fluid for 6 years • 177ºC, 14,000 psi • S13Cr tubing failed from CaCl2 packer fluid • Well worked over and re-completed with Cs formate • 1.4 g/cm3 Na/K formate used as packer fluid • Tubing retrieved 6 years later • Tubing was in excellent condition. 10 John Downs - Formate Brine Ltd
  11. 11. The economic benefits provided by formate brines in HPHT gas field developments Formate brines improve the economics of HPHT gas field developments by :  Reducing well delivery time and costs  Improving operational safety and reducing risk  Delivering production rates that exceed expectations  Providing more precise reservoir definition Detailed explanation and evidence later in this presentation 11 John Downs - Formate Brine Ltd
  12. 12. Formate brines used by OMV in Pakistan in 2005-6 for drill-in and completions in HPHT gas wells 12 John Downs - Formate Brine Ltd
  13. 13. Formate brines used by OMV in Pakistan in 2005-6 for drill-in and completion in HPHT gas wells 13 John Downs - Formate Brine Ltd
  14. 14. www.formatebrines.com Source of all the latest formate information 14 John Downs - Formate Brine Ltd
  15. 15. Useful reference material The Formate Technical Manual - 26 chapters - > 400 pages - Available in English, Spanish and Chinese - Updated and expanded every month Recent SPE papers SPE 130376 (2010): “A Review of the Impact of the Use of Formate Brines on the Economics of Deep Gas Field Development Projects” SPE 145562 (2011): “Life Without Barite: Ten Years of Drilling Deep HPHT Gas Wells With Cesium Formate Brine” 15 John Downs - Formate Brine Ltd
  16. 16. Another source of formate information The Formate Brines group on LinkedIn – www.linkedin.com 16 John Downs - Formate Brine Ltd
  17. 17. And another source of formate information.... The Formate Brines newsletter – Issue #9 out this week 17 John Downs - Formate Brine Ltd
  18. 18. Formate brines – Discovery and qualification by Shell Research Shell patent the use of formates as polymer stabilisers Shell discover cesium formate brine Shell publish first SPE papers on formate brines 1987 1988 1989 1990 1991 1992 Shell R&D in UK study the effect of sodium and potassium formates on the thermal stability of drilling polymers Shell R&D in The Netherlands carry out qualification work on formate brines as deep slim-hole (HPHT) drilling fluids Start of Shell’s deep slim-hole drilling R&D programme 18 John Downs - Formate Brine Ltd
  19. 19. Formate Brines – Properties that make them excellent drilling and completion fluids • Density up to 2.3 g/cm3 and pH 9-10 • Only monovalent ions (Na+, K+, Cs+, HCOO-) • Stabilise shales (K, Cs and low water activity) • Protect polymers at high temperature • Less corrosive than other brines • Good lubricity • Non-toxic and readily biodegradable 19 John Downs - Formate Brine Ltd
  20. 20. Benefits of formate brines – Compatible with polymers, so can be used as drilling fluids A traditional low-solids formate drilling fluid formulation Component Function Concentration Formate brine Density Lubricity Polymer protection Biocide 1 bbl Xanthan Viscosity Fluid loss control 0.75 – 1 ppb Lo- Vis PAC and modified starch Fluid loss control 4 ppb each Sized calcium carbonate Filter cake agent 10 – 15 ppb K2CO3/KHCO3 Buffer Acid gas corrosion control 2 – 8 ppb This simple formulation has been in field use since 1993 – good to 160o C 20 John Downs - Formate Brine Ltd
  21. 21. Formate brines launched as low-solids drilling fluids in mid-1990’s John Downs - Formate Brine Ltd Property Typical values pH 9 – 10.5 PV [cP] 15 - 20 YP [lb/100ft2] 8 - 15 10” gel 2 - 5 10’ gel 3 - 6 HPHT fluid loss [mL] < 10 API fluid loss < 3 Service company brand names: Baker Hughes : CLEAR-DRILL (1994) M-I : FLOPRO (1995) Baroid : BRINEDRIL Filter cake on aloxite disc 21
  22. 22. Benefits of formate brines - they raise the thermal stability ceiling of polymers Bar graph showing the temperature at which polymers lose 50% of their viscosity after 16 hours hot rolling Temperature [deg C] 66 116 166 150 200 250 300 350 400 Temperature [deg F] Starch PAC Xanthan Potassium formate (1.59 sg 13.25 ppg) Sodium formate (1.32 sg 11.05 ppg) Potassium chloride (1.16 sg 9.66 ppg) Sodium chloride (1.19 sg 9.91 ppg) Sodium bromide (1.53 sg 12.75 ppg) Calcium chloride (1.39 sg 11.58 ppg) Freshwater 22 John Downs - Formate Brine Ltd
  23. 23. Benefits of formate brines - ROP enhancement Low-solids formate brines increase drilling ROP by >100% compared to OBM (in carbonates and shale) Effect of Mud on Rate of Penetration Carthage Marble with 7 Blade PDC Bit 50 40 30 20 10 0 Water 16ppg OBM 16ppg CsFm 16ppg OBM + Mn 0 5,000 10,000 15,000 20,000 25,000 30,000 Weight on Bit (lbf) Rate of Penetration (ft/hr) Data from DOE Deep Trek project , see SPE paper 112731 23 John Downs - Formate Brine Ltd
  24. 24. Benefits of formate brines - ROP enhancement Zero-solids formate brines can increase drilling ROP by 200-300% vs WBM Zero-solids potassium formate brines are now breaking records as drilling fluids in the Montney and Duvernay shales in Canada Data from SPE paper 36425 (1996) 24 John Downs - Formate Brine Ltd
  25. 25. Benefits of formate brines - ROP enhancement Ramsey et al found correlation between Fann 600 reading of drilling fluids and ROP in sandstone Note the effect of the calcium carbonate (solids) concentration on Fann 600 reading and ROP with formate brine Data from SPE paper 36396 (1996) 25 John Downs - Formate Brine Ltd
  26. 26. Benefits of formate brines – Zero/low solids gives better hydraulics • Lower Surge and Swab Pressures - Faster tripping times - Reduced risk of hole instability or well control incidents • Lower System Pressure Losses - More power to motor • Lower ECD - Drill in narrower window between pore and fracture pressure gradients - Less chance of fracturing well and causing lost circulation • Higher Annular Flow Rates - Better hole cleaning John 26 Downs - Formate Brine Ltd
  27. 27. Benefits of formate brines – Natural lubricity Steel-steel coefficient of friction in potassium formate brine (BP test) 27 John Downs - Formate Brine Ltd
  28. 28. Benefits of formate brines – Low methane solubility • Low methane solubility and diffusion rates - Easier kick detection - Low rate of static influx • Mud properties not degraded by gas influx Fluid Solubility (kg/m3) Diffusion coefficient (m2/sec x 108) Diffusion flux (kg/m2s x 106) OBM 164 1.15 53.30 WBM 5 2.92 3.98 Formate brine 1 0.80 0.25 Solubility of methane in drilling fluids: T = 300°F (149°C), P = 10,000 psi (690 bar) 28 John Downs - Formate Brine Ltd
  29. 29. Finnish Environment Institute recommends the use of potassium formate in sensitive groundwater areas 29 John Downs - Formate Brine Ltd
  30. 30. Extracts from summary of Finnish Environment Institute report on potassium formate “Potassium formate is already widely used in Finnish airports. According to a recently completed follow-up study conducted over several years, formate biodegrades rapidly in the ground, even at low temperatures. This prevents its infiltration into groundwater” “In Finland, potassium formate is currently the sole de-icing agent used on nine roads crossing valuable groundwater areas…. For the follow-up study, data on groundwater quality was collected from three of the groundwater areas. No negative impacts were observed on groundwater quality, due to the use of potassium formate, at any of the three areas in question” 30 John Downs - Formate Brine Ltd
  31. 31. Extracts from abstracts of Finnish Environment Institute reports on potassium formate Alternative deicing agents and ground water protection. Final report of MIDAS2- project (published 2010) This report summarizes….. novel data from a 7-year follow-up study on the ground water quality at three areas (Kauriansalmi, Taavetti, and Jaamankangas aquifers) where potassium formate has been used as a sole de-icing chemical. On highway 13, running along Kauriansalmi aquifer (Suomenniemi municipality), potassium formate was used as a sole de-icer from 2002 until the end of 2009. During that period, no formate was found in the ground water at the area. The average chloride concentration in the formation has decreased on average by 3,3 % a year since sodium chloride application came to an end in 2002. At Taavetti municipal water intake, chloride concentration decreased sharply after 2004 when potassium formate was introduced in de-icing at the area. This study shows that potassium formate can be applied in winter road maintenance in particular at sensitive ground water areas, and at airports to minimize the adverse impacts on ground and surface water resulting from de-icing. 31 John Downs - Formate Brine Ltd
  32. 32. Formate brines – Production and first field use - Milestones First field use of sodium formate: Shell drills and completes first Draugen oil wells Start of deep HPHT gas well drilling with formates in Germany (Mobil, RWE, Shell) Potassium formate brines used in USA, Canada, Mexico, Venezuela, First field use of potassium formate (with Micromax) : Statoil drills and completes Gullfaks oil well First use of formate brine as packer fluid: Shell Dunlin A-14 1993 1994 1995 1996 1997 1998 Brazil, Ecuador Sodium formate powder available. Draugen wells each produce 48,000 bbl oil /day 1994 - Potassium formate brine becomes available from Norsk Hydro (now Addcon) 1997 - Cesium formate brine becomes available from Cabot 32 John Downs - Formate Brine Ltd
  33. 33. Potassium formate brine has been used to drill deep HPHT gas wells since 1995 First use : ExxonMobil’s Walsrode field, onshore northern Germany - high-angle deep HPHT slim hole low perm gas wells TVD : 4,450-5,547 metres Reservoir: Sandstone 0.1-125 mD BHST : 157o C Section length: 345-650 m Drilling fluid: SG 1.45-1.55 K formate brine 33 John Downs - Formate Brine Ltd
  34. 34. Potassium formate from Addcon used in 15 deep HPHT gas well constructions in Germany ,1995-99 Fluids service provided by M-I and Baroid Well Name Application Fluid Type Density s.g. (ppg) Horizontal Length(m) Angle (°) BHST (°F) BHCT (°F) TVD (metres) MD (metres) Permeability (mD) Walsrode Z5 W/C K Formate 1.55 (12.93) 345 26 315 na 4450 - 4632 4815 - 5151 0.1 - 125 mD Wasrode Z6 W/C K Formate 1.55 (12.93) 420 40 315 na 4450 - 4632 4815 - 5151 0.1 - 125 mD Walsrode Z7 Drill-In K Formate 1.53 (12.77) 690 59 315 295 4541 - 4777 5136 - 5547 0.1 - 125 mD Söhlingen Z3A Drill-In Formix 1.38 (11.52) 855 89 300 270 4908 5600 na Söhlingen Z3a Drill-In Na Formate 1.30 (10.85) 855 89 300 270 4908 5600 na Volkersen Z3 W/C Formix 1.40 (11.68) 512 52 320 na na na na Kalle S108 Drill-In Formix 1.45 (12.10) 431 60 220 na 6000-6500 6200-6600 na Weißenmoor Z1 W/C Formix 1.35 (11.27) 634 31 300 na na na na Idsingen Z1a Drill-In K Formate 1.55 (12.93) 645 61 321 290 4632 - 4800 5257 - 5821 0.1 - 125 mD Söhlingen Z12 Drill-In Na Formate/Formix 1.35 (11.27) 452 28 313 285 4736 - 4937 4846 - 5166 1.0 - 75 mD Simonswolde Z1 Drill-In K Formate/Formix 1.52 (12.68) 567 35 293 275 4267 - 4572 4236 - 4648 0.1 - 25 mD Walsrode NZ1 Drill-In Formix 1.51 (12.60) 460 34 290 265 4632 - 4815 4541 - 4693 0.1 - 125 mD Idzingen Z2 W/C Formix 1.40 (11.68) na na 320 na 4632 - 4800 5257 - 5821 0.1 - 125 mD Voelkersen NZ2 W/C Formix 1.40 (11.680 na na 320 na na na na Söhlingen Z13 Drill-In/Frac K Formate/Formix 1.30 (-1.56)(10.85) 1200 90 300 285 4724 5486 - 6400 0,1 - 150 mD 34 John Downs - Formate Brine Ltd
  35. 35. Summary of potassium formate brine use in HPHT gas wells in Germany,1995-99 35 John Downs - Formate Brine Ltd
  36. 36. Addcon’s potassium formate plant in Norway has been supplying the oil industry since 1994 Production Site ADDCON NORDIC AS Storage tanks for raw materials 36 John Downs - Formate Brine Ltd
  37. 37. Potassium formate production by Addcon • The first and largest producer of potassium formate - Brine production capacity : 800,000 bbl/year - Non-caking powder capacity: 8,400 MT/year • Direct production from HCOOH and KOH • High purity product • Large stocks on quayside location • Fast service – by truck, rail and sea • Supplier to the oil industry since 1994 50 % KOH 4,500 m3 6,300 MT 94 % Formic acid 5,000 m3 Feedstock storage tanks in Norway 37 John Downs - Formate Brine Ltd
  38. 38. Addcon’s new potassium formate plant in Bitterfeld, Germany Only 7 hours drive from Bitterfeld to Vienna area 38 John Downs - Formate Brine Ltd
  39. 39. Potassium formate brine – Methods of shipment 39 John Downs - Formate Brine Ltd
  40. 40. Typical potassium brine grades % w/w Density TCT* SG oC 75 1.57 7 71 1.53 2 63 1.46 -13 * Crystals of potassium formate added to encourage crystallisation 40 John Downs - Formate Brine Ltd
  41. 41. Formate brines – Some important milestones : 1999-2004 First production of non-caking crystalline K formate by Addcon First drilling jobs with K/Cs formate brine: Huldra and Devenick HPHT First use of Cs-weighted LSOBM as perforating completion fluid (Visund) 1999 2000 2001 2002 2003 2004 First of 14 Kvitebjørn HPHT wells drilled and completed with K/Cs formate brines Formate brines used as packer fluids for HPHT wells in GOM. First well : ExxonMobil’s MO 822#7 (215oC BHST) in 2001 Use of Cs-weighted oil-based completion fluids for oil reservoirs : Visund, Statfjord, Njord, Gullfaks, Snorre , Oseberg, Rimfaks 2001 – present First use of K/Cs formate brine : Completion job in Shearwater well (Shell UK) Cs-weighted LSOBM used as OH screen completion fluid (Statfjord) First use of K/Cs formate brine as HPHT well suspension fluid (Elgin) Individual Draugen oil wells (1993) and Visund oil wells (2003) have similar flow rates of around 50,000 bbl oil/day 41 John Downs - Formate Brine Ltd
  42. 42. Cesium formate produced by Cabot in Canada from pollucite ore Pollucite ore Cs0.7Na0.2Rb0.04Al0.9Si2.1O6·(H20) • Mined at Bernic Lake, Manitoba • Processed on site to Cs formate brine • Cs formate brine production 700 bbl/month • Cs formate stock built up to 30,000 bbl 42 John Downs - Formate Brine Ltd
  43. 43. The first sustained use of K/Cs formate brine was in the world’s largest HPHT gas field development Elgin/Franklin field – UK North Sea Cesium formate brine used by TOTAL in 34 well construction operations in 8 deep gas fields in period 1999-2010 43 John Downs - Formate Brine Ltd
  44. 44. Formate brines – Some published milestones 2005 -2010 OMV Pakistan start using K formate to drill and complete (with ESS) in HPHT gas wells Saudi Aramco start using K formate to drill and complete (with ESS) in HPHT gas wells Gravel pack with K formate brine in Statfjord B First MPD operation in Kvitebjørn with K/Cs formate “designer fluid” First of 12 completions in the Kashagan field with K/Cs formate Petrobras use K formate brine for open hole gravel packs in Manati field 2005 2006 2007 2008 2009 2010 Total’s West Franklin F9 well (204oC) perforated in K/Cs formate brine K/Cs formate brines used as well perforating fluids in 11 HPHT gas fields in UK North Sea : Dunbar, Shearwater, Elgin, Devenick , Braemar , Rhum, Judy , Glenelg , Kessog , Jura and West Franklin 1999-2011 44 John Downs - Formate Brine Ltd
  45. 45. Saudi Aramco have been drilling HPHT gas wells with potassium formate brine since 2003 45 John Downs - Formate Brine Ltd
  46. 46. Saudi Aramco use of formate brines, 2003-2009 • 7 deep gas fields • 44 HPHT wells drilled • 70,000 ft of reservoir drilled at high angle • 90,000 bbl of brine recovered and re-used • Good synergy with ESS, also OHMS fracturing 46 John Downs - Formate Brine Ltd
  47. 47. Summary from Aramco’s OTC paper 19801 Aramco consume around 300 m3/month of K formate brine 47 John Downs - Formate Brine Ltd
  48. 48. Potassium formate brine weighted with Micromax® in Kuwait and Saudi Arabia Good results in first 9 HPHT wells – could become the standard HPHT fluid for KOC SPE 132151 (2010) “Successful HPHT Application of Potassium Formate/Manganese Tetra-Oxide Fluid Helps Improve Drilling Characteristics and Imaging Log Quality” SPE/IADC 147983 (2011) “Utilization of Non-damaging Drilling Fluid Composed of Potassium Formate Brine and Manganese Tetra Oxide to Drill Sandstone Formation in Tight Gas Reservoir SPE 163301 (2012) “Paradigm Shift in Reducing Formation Damage: Application of Potassium Formate Water Based Mud in Deep HPHT Exploratory Well” 48 John Downs - Formate Brine Ltd
  49. 49. Potassium formate brine weighted with Micromax for drilling deep HPHT fractured carbonate wells 10,000 psi, 140oC, H2S = 4-12%, CO2 = 1-6% 49 John Downs - Formate Brine Ltd
  50. 50. Potassium formate brine weighted with Micromax for drilling deep HPHT fractured carbonate wells “The results were extraordinary when compared to wells drilled with ..OBM” – Production rates x 3 higher 50 John Downs - Formate Brine Ltd
  51. 51. Pakistan - OMV use potassium formate brine for HPHT deep gas well drilling and completions 51 John Downs - Formate Brine Ltd
  52. 52. Extracts from OMV’s SPE papers and SPE presentations – note 1,700 psi overbalance, and 350oF 52 John Downs - Formate Brine Ltd
  53. 53. OMV drills and completes using ESS in potassium formate brine – Pakistan, 2006/7 53 John Downs - Formate Brine Ltd
  54. 54. Norway, 2002 - Perforating in solids-free oil-based kill pill weighted with formate brine • Visund field - BHST: 118o C - Fluid density: SG 1.65 - 13 wells – 1000- 2000 metre horizontal sections - Drilled with OBM ,completed with perforated liners • Justification for use: - First 3 wells badly damaged by CaBr2 kill pill - PI only 60-90 m3/bar/day 54 John Downs - Formate Brine Ltd
  55. 55. Perforating Visund wells in solids-free oil-based kill pill weighted with formate brine • Visund – Change to formate kill pill (see SPE 73709, 58758 and 84910) - Next 3 wells perforated in formate fluid -Also used new perforating guns, in dynamic underbalance • Results : - Eliminated formation damage problem - PI increased up to 900 m3/bar/day - 300-600% PI improvement - Best well : 53,000 bbl/day Visund well productivity 60 70 50 220 620 900 1000 900 800 700 600 500 400 300 200 100 0 Well m3 oil/bar/day Formate brine Bromide brine 55 John Downs - Formate Brine Ltd
  56. 56. Formate brines used as HPHT cased well completion fluids after drilling with OBM Formate brines have been used as (perforating) completion fluids for cased wells in 9 HPHT gas fields in the North Sea • Shearwater • Elgin/Franklin • Braemar • Rhum • Judy • Glenelg • Kessog • Jura • West Franklin 56 John Downs - Formate Brine Ltd
  57. 57. Managed Pressure Drilling and completion of fractured carbonates with formate brine SPE 165761 (2012) “ Experience with Formate Fluids for Managed Pressure Drilling and Completion of Sub-Sea Carbonate Gas Development Wells” • Petronas - Kanowit field – 2 sub-sea gas wells • Managed Pressure Drilling in fractured carbonate with K formate brine improved economics by: - Minimising fluid losses - Reducing fluid cost (by using K formate) - Improving production by 50% - Eliminating need for stimulation (no acidising) 57 John Downs - Formate Brine Ltd
  58. 58. Kanowit SS-1 : Production profile from start-up - natural clean-up – no stimulation . Carbonate reservoir • 100 MMscfd gas and 4,000 bpd condensate after 5 hours • >150 MMscfd gas and > 6,000 bpd condensate after 9 hours
  59. 59. Kanowit SS-1 : Multi-rate well test results from carbonate Both wells can produce > 150 MMscfd gas and > 6,000 bpd condensate MRT measurements on well SS-1 before acidizing (Mahadi et al, 2013) MRT Test Choke size (/64) Well Head Pressure (psi) Gas Flow rate Choke correlation (MMscfd) Gas Flow rate Sonar (MMscfd) PDG Pressure (psi) PDG Temp (oF) 1 112 2874.4 159.16 147.61 3857.0 252 2 88 3273.0 111.85 108.76 3932.2 252 3 64 3476.8 63.46 64.51 3978.5 251.7 4 40 3560.5 25.84 28.01 3998.8 250.1 The maximum potential flow rate figures are 50% higher than the technical potential predicted in the original field development plan.
  60. 60. North Sea - Formate brines used as combined HPHT drill-in and completion fluids 33 development* wells drilled and completed in 7 HPHT offshore gas fields • Huldra (6 ) • Tune (4) • Devenick (2) • Kvitebjoern (8 O/B and 5 MPD) • Valemon (1) • Kristin (2) – Drilled only • Vega (5) * Except Valemon (appraisal well) Mostly open hole stand-alone sand screen completions 60 John Downs - Formate Brine Ltd
  61. 61. Tune field – HP/HT gas condensate reservoir drilled and completed with K formate brine, 2002 4 wells : 350-900 m horizontal reservoir sections. Open hole screen completions. Suspended for 6-12 months in formate brine after completion 61 John Downs - Formate Brine Ltd
  62. 62. Tune wells - Initial Clean-up – Operator’s view (direct copy of slide) June 2003 • Wells left for 6-12 months before clean-up • Clean-up : 10 - 24 hours per well • Well performance • Qgas 1.2 – 3.6 MSm3/d • PI 35 – 200 kSm3/d/bar • Well length sensitive • No indication of formation damage Well length [m MD] • Match to ideal well flow simulations (Prosper) - no skin • Indications of successful clean-up • Shut-in pressures • Water samples during clean-up • Formate and CaCO3 particles • Registered high-density liquid in separator • Tracer results Before After • A-12 T2H non detectable • A-13 H tracer indicating flow from lower reservoir first detected 5 sd after initial clean-up <-> doubled well productivity compared to initial flow data • No processing problems Oseberg Field Center SIWHP SIDHP SIWHP SIDHP bara bara bara bara A-11 AH 169 - 388 - A-12 T2H 175 487 414 510 A-13 H 395 514 412 512 A-14 H 192 492 406 509 3350 3400 3450 3500 3550 3600 0 100 200 300 400 500 600 700 800 900 1000 Depth [m TVD MSL] A-11AH A-12HT2 A-13H A-14H A-11 AH plugged back 62 John Downs - Formate Brine Ltd
  63. 63. Tune – Production of recoverable gas and condensate reserves since 2003 (NPD data) Good early production from the 4 wells - No skin (no damage) - 12.4 million m3 gas /day - 23,000 bbl/day condensate Good sustained production - 90% of recoverable hydrocarbon reserves produced by end of Year 7 NPD current estimate of RR: - 18.3 billion m3 gas - 3.3 million bbl condensate Rapid and efficient drainage of the reservoir 63 John Downs - Formate Brine Ltd
  64. 64. Huldra field – HPHT gas condensate reservoir drilled and completed with formate brine, 2001 • 6 production wells • 1-2 Darcy sandstone • BHST: 147oC • TVD : 3,900 m • Hole angle : 45-55o • Fluid density: SG1.89-1.96 • 230-343 m x 81/2” reservoir sections • Open hole completions, 65/8” wire wrapped screens • Lower completion in formate drilling fluid and upper completions in clear brine John 64 Downs - Formate Brine Ltd
  65. 65. Comments from Huldra project manager 65 TROND JUSTAD Manager-Huldra Project Bergen, Norway “CESIUM FORMATE HAS PLAYED A KEY ROLE in the development of the Huldra field (a high-temperature, high-pressure gas field being developed by Statoil in the North Sea). Without it Statoil could not have developed the field without major consequences on our plans, including the very expensive redesign of all wells. The need to use a cesium formate-based drilling fluid became clear after we experienced severe operational limitations when we drilled the first reservoir section with a different product. Also, quite early in the process, we found that good synergies could be achieved when using the same fluid for the drilling and completion phases. “Cesium formate has significantly improved the safety and well control aspects of the project. It has demonstrated good drillability with good hole cleaning, faster tripping speeds and absolutely no sag. During flow checks, the fluid is completely stable after only 20 minutes, compared to 45 to 60 minutes when using another product. This results in significant savings on every trip, as several flow checks must be done each time the drill string is run in and out of a high-temperature, high-pressure well. “For the specific conditions of the Huldra field, there is no realistic fluid alternative for successfully drilling and completing the wells” - TROND JUSTAD John Downs - Formate Brine Ltd
  66. 66. Huldra – Production of recoverable gas and condensate reserves since Nov 2001 (NPD data) Plateau production from first 3 wells - 10 million m3 gas /day - 30,000 bbl/day condensate Good sustained production - 78% of recoverable gas and 89% of condensate produced by end of Year 7 - Despite rapid pressure decline..... NPD current estimate of RR: - 17.5 billion m3 gas - 5.1 million bbl condensate Rapid and efficient drainage of the reservoir 66 John Downs - Formate Brine Ltd
  67. 67. Kvitebjørn field – HPHT gas condensate reservoir drilled and completed with K/Cs formate brine, 2004-2013 • 13 wells to date – 8 O/B, 5 in MPD mode • 100 mD sandstone • BHST: 155oC • TVD : 4,000 m • Hole angle : 20-40o • Fluid density: SG 2.02 for O/B • 279-583 m x 81/2” reservoir sections • 6 wells completed in open hole : 300-micron single wire-wrapped screens. • Remainder of wells cased and perforated John 67 Downs - Formate Brine Ltd
  68. 68. A few of the highlights from Kvitebjoern Fast completions and high well productivity Kvitebjoern well Completion time (days) A-4 17.5 A-5 17.8 A-15 14.8 A-10 15.9 A-6 12.7 * Operator comments after well testing (Q3 2004 ) * Fastest HPHT well completion in the North Sea “The target well PI was 51,000 Sm3/day/bar This target would have had a skin of 7” “A skin of 0 would have given a PI of 100,000” “THE WELL A-04 GAVE A PI OF 90,000 Sm3/day/bar (ANOTHER FANTASTIC PI)” The Well PI was almost double the target 68 John Downs - Formate Brine Ltd
  69. 69. Kvitebjørn– Production of recoverable gas and condensate reserves since Oct 2004 (NPD data) Good production reported from first 7 wells in 2006 - 20 million m3 gas /day - 48,000 bbl/day condensate Good sustained production (end Y8) - 37 billion m3 gas - 17 million m3 of condensate - Produced 70% of original est. RR by end of 8th year NPD : Est. RR have been upgraded - 89 billion m3 gas (from 55) - 27 million m3 condensate (from 22) Note : Shut down 15 months, Y3-5 - To slow reservoir pressure depletion - Repairs to export pipeline 69 John Downs - Formate Brine Ltd
  70. 70. Economic benefits of using formate brines • SPE 130376 (2010): “A Review of the Impact of the Use of Formate Brines on the Economics of Deep Gas Field Development Projects” • SPE 145562 (2011): “Life Without Barite: Ten Years of Drilling Deep HPHT Gas Wells With Cesium Formate Brine” 70 John Downs - Formate Brine Ltd
  71. 71. Economic benefits from using formate brines - Latest paper 71 John Downs - Formate Brine Ltd
  72. 72. Economic benefits from using formate brines - Good well performance and recovery of reserves • “High production rates with low skin” * • “ We selected formate brine to minimise well control problems and maximise well productivity”* * Quotes by Statoil relating to Kvitebjoern wells (SPE 105733) 72 John Downs - Formate Brine Ltd
  73. 73. Economic benefits from using formate brines - More efficient and safer drilling Better/safer drilling environment saves rig-time costs • Stable hole: see LWD vs. WL calipers in shale • Elimination of well control* and stuck pipe incidents • Good hydraulics, low ECD • Good ROP in hard abrasive rocks * See next slide for details “ a remarkable record of zero well control incidents in all 15 HPHT drilling operations and 20 HPHT completion operations” 73 John Downs - Formate Brine Ltd
  74. 74. Formate Brines : Allow fast solids-free drilling Solids-free formate brines drill deep horizontal well sections much faster than muds like OBM – and cause less formation damage 74 John Downs - Formate Brine Ltd
  75. 75. Economic benefits from using formate brines - Improved well control and safety • Elimination of barite and its sagging problems • Elimination of oil-based fluids and their gas solubility problem • Low solids brine  Low ECD (SG 0.04-0.06) and swab pressures • Inhibition of hydrates • Ready/rapid surface detection of well influx • Elimination of hazardous zinc bromide brine 75 John Downs - Formate Brine Ltd
  76. 76. Economic benefits from using formate brines - More efficient/faster completions - Drill-in and completing with formate brine allows open hole completion with screens - Clean well bores mean no tool/seal failures or blocked screens - Completion time 50% lower than wells drilled with OBM “ fastest HPHT completion operation ever performed in North Sea (12.7 days)” 76 John Downs - Formate Brine Ltd
  77. 77. Economic benefits from using formate brines • No differential sticking • Pipe and casing running speeds are fast • Mud conditioning and flow-check times are short • Displacements simplified, sometimes eliminated Flow check fingerprint for a Huldra well Duration of flow back (minutes) Fluid Gain (bbl) 30 0.8 15 0.56 20 0.44 30 0.56 - Operational efficiencies 77 John Downs - Formate Brine Ltd
  78. 78. Economic benefits from using formate brines - Good reservoir definition if Cs present in fluid • High density filtrate and no barite • Filtrate Pe up to 259 barns/electron • Unique Cs feature - makes filtrate invasion highly visible against formation Pe of 2-3 b/e • LWD can “see” the filtrate moving (e.g. see the resistivity log on far right – drill vs ream • Good for defining permeable sands (see SAND-Flag on log right ) • Consistent and reliable net reservoir definition from LWD and wireline 78 John Downs - Formate Brine Ltd
  79. 79. Economic benefits from using formate brines - Good reservoir imaging • Highly conductive fluid • Clear resistivity images • Information provided: - structural dip - depositional environment - geological correlations 79 John Downs - Formate Brine Ltd
  80. 80. Formate brines – Summary of economic benefits provided to users Formate brines improve oil and gas field development economics by :  Reducing well delivery time and costs  Improving well/operational safety and reducing risk  Maximising well performance  Providing more precise reservoir definition 80 John Downs - Formate Brine Ltd
  81. 81. Formate brines enable open-hole screen completions in high-angle HPHT wells Formate brines are low-solids drill-in and completion fluid systems that provide massive benefits in open-hole screen completions in HPHT wells • Generally non-damaging to reservoir and screens • Clean-up naturally during start-up (10-20 hours) • Low skins • No well stimulation required • Good with expandable screens (Saudi, Pakistan) Formates are perhaps the only high-density fluids that routinely deliver unimpaired open hole screen completions in HPHT wells John Downs - Formate Brine Ltd
  82. 82. Finnish Environment Institute recommends the use of potassium formate in sensitive groundwater areas Environ Sci Technol. 2005 Jul 1;39(13):5095-100. Use of potassium formate in road winter deicing can reduce groundwater deterioration. Hellstén PP1, Salminen JM, Jørgensen KS, Nystén TH. “Potassium formate was used to de-ice a stretch of a highway in Finland. The fate of the formate was examined by monitoring the groundwater chemistry in the underlying aquifer of which a conceptual model was constructed. In addition, we determined aerobic and anaerobic biodegradation rates of formate at low temperatures (-2 to +6 degrees C) in soil microcosms. Our results show that the formate did not enter the saturated zone through the thin vadose zone; thus, no undesirable changes in the groundwater chemistry were observed. We recorded mineralization potential up to 97% and up to 17% within 24 h under aerobic and anaerobic conditions, respectively, in the soil and subsurface samples obtained from the site. This demonstrates that biodegradation in the topsoil layers was responsible for the removal of the formate. We conclude that the use of potassium formate can potentially help diminish the negative impacts of road winter deicing on groundwater without jeopardizing traffic safety.” 82 John Downs - Formate Brine Ltd

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