A sustainable solution replacing an active and inefficient Dual Phase Extraction System

Transcription

1 A sustainable solution replacing an active and inefficient Dual Phase Extraction System Joyce Cruz - Project Geologist joyce.cruz@ch2m.com João Marcellino Project Manager joao.marcellino@ch2m.com Olivier Maurer Senior Technologist olivier.maurer@ch2m.com Christian Nogueira Senior Reviewer christian.nogueira@ch2m.com Renata Moura Petrom Contract Manager - renata.moura@petrom.com.br

2 Schedule Introduction NAPL distribution model Conceptual approach Construction Conclusions 2

3 3 A sustainable solution replacing an active and inefficient Dual Phase Extraction System

4 Introduction We will present the main steps of a Permeable Adsorp5ve Barrier system at the a chemical facility near São Paulo Brazil (Petrom, Mogi das Cruzes). : - to design - construct, - and operate Dual- Phase Extrac5on System in opera5on since 2007 to treat LNAPL, not sufficient enough and not sustainable. APer revising the Site Conceptual Model (CSM) a Passive Barrier System was viewed as a more sustainable solu5on to prevent poten5al light non- aqueous phase liquid (LNAPL) (di(2- ethylhexyl)phthalate (DEHP) and di- n- butyl phthalate (DBP)) from entering a channelized water stream crossing the facility, the main environmental receptor. 4

5 Localization The image cannot be displayed. Your computer may not have enough memory to open the image, or the image may have been corrupted. Restart your computer, and then open the file again. If the red x still appears, you may have to delete the image and then insert it again. 5

6 New Conceptual Site Model (CSM) Provided the necessary support for the technical team to propose a modification on the remedial approach to CETESB, with the replacement of the existing MPE system for a permeable reactive barrier (PAB wall). Main receptor of concern, not yet impacted. Lost on MPE System efficiency Significant long term expenditures, without knowing the closure plan Company was looking for a consulting firm with exp. on Sustainable Remediation 6

7 Petrom Study Case 2013 first steps, select a more sustainable solution and gain support from authorities Review and revision of existing conceptual site model (CSM) and Human Health Risk Assessment, Presentation to CETESB of new remedial concept and approval 2014 Barrier Construction 2015 Cetesb presentation 2015 Dual system evaluation Suggested that the free product plume was relatively stable with low mobility Narrow Valley NAPL containing di(2- ethylhexyl)phthalate (DEHP) and di-n-butyl phthalate (DBP) 7

8 MPE System Loss of Efficiency! Product removed from1999 to sept/2006: L! Clear lost on efficiency! Heavy O&M scope, costs and energy consumption Volume of Extract Product Volume (Liters) Acumulated(Liters) 8

9 NAPL Distribution Model 9 Presentation Title

10 Bis[2-ethylhexyl]phtalate Soil Plume Barrier Wall 10 Figure 1 Bis [2-ethylhexyl] phthalate Soil Plume Petrom Mogi Das Cruzes, Brazil

11 0,1 % NAPL Saturation Plume Barrier Wall Culverted Stream 11 Figure 2a 0.1% LNAPL Saturation Plume Petrom Mogi Das Cruzes, Brazil

12 0,5 % NAPL Saturation Plume Barrier Wall 12 Figure 2b 0.5% LNAPL Saturation Plume Petrom Mogi Das Cruzes, Brazil

13 1,0 % NAPL Saturation Plume Barrier Wall 13 Figure 2c 1.0% LNAPL Saturation Plume Petrom Mogi Das Cruzes, Brazil

14 2,0 % NAPL Saturation Plume Barrier Wall 14 Figure 2d 2.0% LNAPL Saturation Plume Petrom Mogi Das Cruzes, Brazil

15 Conceptual Approach 15 Presentation Title

16 New Remedial System (PAB) Passive Adsorptive Barrier, using the natural GW flow to protect the primary receptor as well as collecting the free phase and treating the dissolved phase Added collection trench associated with 2 sumps and skimmers PMs to monitor and control the system performance 16

17 Construction 17 Presentation Title

18 The Barrier System 4 main components: 1. LNAPL interceptor and a recovery trench; 2. Situated immediately upgradient of the PAB; 3. Cement- bentonite (CB) slurry wall sec5ons; 4. Sumps to recover and prevent LNAPL from accumula5ng at the upgradient faces of both wall sec5ons. Design: Based on nature and es5mated quan55es of LNAPL Three key issues : 1. Preven5ng migra5on of the LNAPL through the PAB wall; 2. Clogging of the PAB wall by LNAPL; and, 3. Preven5ng migra5on of dissolved COCs through the PAB wall. 18

19 Layout 19

20 Cement-bentonite Barrier Two cement- bentonite barriers were built in order to drive groundwater flow to the Drainage Barriers to the Adsorp5ve Permeable Sec5on; First barrier: 68 meters in length, depth of 4 meters and average width of 0.70 meters; Second barrier: 25 meters long, depth of 4 meters and 0.70 meters width; Preven5ng that the supernatant free phase contact the Tributary of Oropó Stream. 20

21 Cement-bentonite Barrier 21

22 Gravel Trench Draining Barrier The Draining Barrier was built about 30 meters, average width of 0.80 meters and depth of 2.70 meters; Lined with geotex5le (Bidim) and filled with graded gravel (#2); Two wells to extract product (with skimmers); To focus the groundwater flow (and free phase product), direct it to the collec5on wells. 22

23 Gravel Trench 23

24 Permeable Adsorptive Barrier (PAB) Filtering Barrier or Permeable Adsorp5ve Barrier (PAB) Excavated with dimensions of 4.6x3.50 meters with depth of 4 meters, forming a filter box, "enveloped" by a permeable geosynthe5c. 24

25 Barriers Section 25

26 Conclusions 26 Presentation Title

27 Conclusions The system has collected more than 10,000 liters of product. Less O&M Energy consumption Carbon footprint, Innovation in Brazil Favorizing operation by local resources 27

28 Thanks