EVALUATION OF REED CANARY GRASS AS AN ENHANCER FOR LANDFARMS TREATING REFINERY SLUDGES: GREENHOUSE AND FIELD TEST RESULTS.

Transcription

1 EVALUATION OF REED CANARY GRASS AS AN ENHANCER FOR LANDFARMS TREATING REFINERY SLUDGES: GREENHOUSE AND FIELD TEST RESULTS. Les Stehmeier, Frank van Delft (NOVA Chemicals, Canada) Jan Slaski (Alberta Research Council, Canada)

2 Outline History of NOVA Chemicals involvement in phytoremediation Greenhouse studies Field studies Future work

3 The Beginning Control 2 18 Response (mv) Treated Tim e - M inutes

4 Field A Field B Best Fit The Beginning % C i Sampling Points (Days)

5 Summary Initial work in the lab saw 5% reduction of used motor oil with alfalfa. Field trial on two fields reduced oil and grease by >3% in 9 days and allowed additional spreading before the end of the season. Sites were happy with the results!

6 Greenhouse Studies - Past

7 Greenhouse Studies - Past 4 35 Biomass (g/pail) Above Ground Biomass Roots 5 alfalfa reed canary sweet clover 25 % Loss from Weathered Landfarm Soil Alfalfa Reed Canary Grass Sweet Clover Control

8 C32 - C36 C36 - C4 C4 - C42 C28 - C32 C24 - C28 Greenhouse Studies - Past Control Alfalfa Sweet Clover Reed Canary Grass % Off C6 - C7 C7 - C8 C8 - C9 C9 - C1 C1 - C11 C11 - C12 C12 - C14 C14 - C15 C15 - C16 C16 - C17 C17 - C18 C18 - C2 C2 - C24 9 Carbon Number Range Rhizoplane Rhizosphere Loose Bulk Substrate Utilization (%) 55 5 Alfalfa Sweet clover Reed Canary Grass Control

9 Greenhouse Studies - Past Summary Reed Canary Grass is more robust than alfalfa or sweet clover. RCG enhances the performance of the active landfarm soil. The increased root surface area appears to provide the edge

10 16 Oil and Grease (%) Cont SWG RCG HM Greenhouse Studies - Present weeks 9 weeks 13 weeks 19 weeks Oil and Grease (%) Cont 1X SWG 1X RCG 1X HM 1X Oil and Grease (%) Cont 2X SWG 2X RCG 2X HM 2X weeks 9 weeks 13 weeks 19 weeks 4 2 weeks 9 weeks 13 weeks 19 weeks

11 Greenhouse Studies - Present Change in Total Extractable Hydrocarbon (%) Sludge addition Weeks 2 SWG 1X HM 1X RCG 1X SWG 2X HM 2X RCG 2X Final Biomass (g) SWG SWG 1X SWG 2X RCG RCG 1X RCG 2X HM HM 1X HM 2X

12 Greenhouse Studies - Present 3% HM Metal Uptake (% of initial) 25% 2% 15% 1% 5% 1X Sludge Addition 2X Sludge Addition % Ag Al As B Ba Be Bi Ca Cd Cl Co Cr Cu Fe Li Mn Mo Ni Pb Sb Se Sn Sr Th Ti Tl U V Zn

13 Greenhouse Studies - Present 4% SWG Metal Uptake (% of initial) 35% 3% 25% 2% 15% 1% 5% 1X Sludge Addition 2X Sludge Addition % Ag Al As B Ba Be Bi Ca Cd Cl Co Cr Cu Fe Li Mn Mo Ni Pb Sb Se Sn Sr Th Ti Tl U V Zn

14 Greenhouse Studies - Present 4% RCG Metal Uptake (% of initial) 35% 3% 25% 2% 15% 1% 5% 1X Sludge Addition 2X Sludge Addition % Ag Al As B Ba Be Bi Ca Cd Cl Co Cr Cu Fe Li Mn Mo Ni Pb Sb Se Sn Sr Th Ti Tl U V Zn

15 Greenhouse Studies - Present Greenhouse studies provided data showing rhizodegradation significantly reduced hydrocarbon content when compared to unplanted controls. Growth of all three crops appeared to establish a biodegrading community (rhizodegradation) that metabolised sludge at normal and twice normal application rates and was independent of sustainable plant growth. The superiority of RCG was shown by its ability to germinate and grow in soil that received twice the normal sludge application. The growth of plants increased microbial diversity significantly when compared against fallow soil that received sludge. There was also a significant increase in microbial diversity when sludge was applied at twice normal rates compared to normal rates.

16 Greenhouse Studies - Present Phytoextraction occurred in all crops with RCG extracting the most elements at all sludge application rates. SWG extracted 66% of the analysed metals at normal sludge application rates compared to RCG extraction of 48%. At twice the sludge application rate, RCG was able to extract 59% of the elements while SWG and HM failed to extract more than 3% and 4% of the metals, respectively. RCG is a candidate for enhancing the sustainability of refinery sludge treatment by landfarms.

17 Greenhouse Studies - Present

18 Field Studies - Present

19 Field Studies - Present

20 Oil Found the in Topsoil (3cm depth) During 24 Season (kg) Field Studies - Present Start Final #5 #6 #7 #8 Landfarm Field Location #5 #6 #7 #8 Landfarm Field Location Oil Degraded in the Topsoil (3cm depth) During the 24 Season (kg)

21 Field Studies - Present 4 µg INTF/.5 g soil/15 min April June August September November 5 5A Topsoil 5A Subsoil 5B Topsoil 5B Subsoil 5C Topsoil 5C Subsoil

22 25 25 Field Studies - Present Metal Concentration (ppm) Cu Cr Ni V Pb Al Al Concentration (ppm) 4-Mar-4 23-Apr-4 12-Jun-4 1-Aug-4 2-Sep-4 9-Nov-4 29-Dec Metal Concentration (ppm) 15 1 Cu Cr Ni V Pb Al 15 1 Al Concentration (ppm) Metal Concentration (ppm) 15 1 Cu Cr Ni V Pb Al 15 1 Al Concentration (ppm) Mar-4 23-Apr-4 12-Jun-4 1-Aug-4 2-Sep-4 9-Nov-4 29-Dec-4 4-Mar-4 23-Apr-4 12-Jun-4 1-Aug-4 2-Sep-4 9-Nov-4 29-Dec-4

23 Field Studies - Summary

24 Field Studies - Summary The quantity and quality of RCG growth was compromised by the wet conditions experienced in the landfarm soil in 24. Sequestering of metals did not occur in the landfarm and this may be due to the immature crop and minimal growth experienced during 24. The greatest oil and grease loss of mass for four comparable fields was in Field 5, indicating even weak growth of RCG will enhance the rhizodegradation of the sludge applied to the landfarm. Growth of RCG stimulates microbial activity in the landfarm in the topsoil and subsoil. RCG enhances rhizodegradation even when environmental conditions are causing a decrease in biodegradation of non-planted fields.

25 Future Work Four fields will be tested in 25 RCG Proprietary amendment Control Another Crop Full field should allow more reliable results Working with contractor to enable spreading while crop is growing, allowing a full growing season. Hopefully the weather will cooperate.