Introduction to COAL2GAS Project. Final Workshop 27 th of June 2017, Craiova Romania C. Vasile, M. Dobrin

Transcription

1 Introduction to COAL2GAS Project Final Workshop 27 th of June 2017, Craiova Romania C. Vasile, M. Dobrin

2 Contents Rationale and scope of COAL2GAS project COAL2GAS activities: Data Analysis and Site Selection Testing and Drilling Panel and Well Design & Engineering for Integrity and Safety Risk Analysis Proposals for syngas utilisation Conclusions

3 Rationale / starting point for COAL2GAS It is widely accepted that UCG has a great potential to provide cleaner energy than direct combustion of coal in power plants. UCG is capable of replacing traditional mining methods, particularly access and exploit resources that cannot be mined economically with other technologies. UCG pilot projects have recently been carried or commenced in several countries focusing besides developing the technology on safe and environmentally friendly operations and particularly on the problem of groundwater contamination. These problems are of paramount importance in cases where UCG is performed in abandoned mining areas and at shallow depths. Tests of gasifying lignite at relatively shallow depths are quite rare even though many underground lignite mines have been abandoned with vast resources remaining. The general feasibility of gasifying these resources has been proven but it has to be confirmed if the technology could be implemented under EU standards. While the general technical feasibility is widely confirmed, remaining underground workings and the effectivity of mine closure procedures, as well as the influence of UCG on the shallow subsurface and the surface itself are to be investigated.

4 COAL2GAS: Project Overview Project data: Funding Programme: Research Fund for Coal and Steel (RFCS) Grant Agreement No: RFCR CT Duration: July 2014 June 2017 Budget: 2,210,343 COMPLEXUL ENERGETIC OLTENIA

5 COAL2GAS: Objectives Main objective: Evaluation of the UCG feasibility in shallow lignite seams, geologically, technically and environmentally and to illustrate this for a selected deposit in Romania Methods / Tools / Approaches: Data Analysis and Site Selection Testing and Drilling Panel & Well Design and Engineering for Integrity and Safety Geomechanical modeling (2D, 3D) to analyze the stability of the UCG cavity Risk Analysis Design of plans for monitoring the process and the environmental factors

6 Data Analysis and Site Selection Detailed comparison of the 4 proposed sites in the Oltenia region: 1) Plostina 2) Lupoaia Prigoroiu 3) Tehomir 4) Urdari Valeacu Apa

7 Data Analysis and Site Selection Site selection on the basis of choosing a location with the presence of coal seams 5 to 8 with thicknesses above 2 m and at a suitable depth below surface selected site: Urdari 5 exploration borehole locations have been proposed. Overview of Urdari exploration site with proposed drill holes (green dots)

8 Setup of 3D model Following site selection a 3D geological model using Petrel has been set up. The model represents the currently best representation of the geological situation at the Urdari site. Cross sections of Urdari mine perimeter in 3D view with drill holes including stratigraphic logs and markers. View from SE, Z scale 2:1

9 Setup of 3D model The proposed drill hole locations included into the modeling platform for visualization purposes in conjunction with the model EU DEM topography layer with superimposed satellite imagery and proposed drill holes as well as modeled horizons for seam bases VIII and V, view from SW, Z scale 2:1

10 Geological and coal parameters of other deposits Based on established criteria and the available information the characteristics of selected deposits was performed. This study will help in identifying suitable sites and prioritized them according their suitability for UCG process. Poland Gostyń Kamieńsk Krzywiń Ścinawa Głogów Torzym Węglewice Greece Kozani Florina Prosilio Almyros Western Deposit Almyros Eastern Deposit Slovenia Velenje Šoštanj Lendava Globoko Ilirska Bistrica Krmelj Kanižarica Romania Lupoaia Ploştina Nord Tehomir Urdari Valea cu apă Germany Rhineland area Lusatian area Central German area Helmstedt area

11 Characterization of coal bulk samples Slovenian lignite (Velenje) Romanian lignite (Oltenia) 14 t 12 t Coal characterization GIG 5 kg samples Slovenian lignite lab tests CERTH Atmospheric pressure UCG tests Romanian lignite lab tests High pressure UCG tests

12 Large scale gasification experiments Two atmospheric pressure UCG tests (Romanian and Slovenian coals) Two high-pressure UCG tests (Romanian and Slovenian coals) Investigations during experiments: the role of gasification mixture and coal properties on coal gasification rates, composition of products and process efficiency, the influence of natural coal moisture, the role of selected parameters on the formation, release and migration of UCGrelated contaminants Investigations during experiments: the changes in the UCG process efficiency under a high pressure gasification regime, the role of gasification mixture and coal properties on coal gasification rates under high pressure regime, the influence of elevated pressure on the formation, release and migration of UCGrelated environmental contaminants

13 Atmospheric pressure gasification tests

14 High pressure gasification tests Ex situ simulation of high pressure UCG Technical parameters: coal type: lignite, hard coal coal seam length: 3.5 m gasification pressure: max 50 bar gasification temperature: max C coal seam inclination: 0, 15, 30, 45 0

15 Assessment of UCG related contaminants Gasification stage Contaminants in post processing waters Post gasification stage Contaminants in solid UCG by products (char, ash, slag)

16 Assessment of UCG related contaminants High pressure (10 bar) UCG simulation: Wastewaters Raw UCG-gas T, p Condensate removal valve Condensate sampling valve

17 Assessment of UCG related contaminants Post gasification studies Tests on post gasification solid residues: Chemical composition, Physical changes (porosity, fractures, etc.) Mechanical properties

18 Test drilling Name Length [m] Inner Pipe Diameter [mm] Wall Thickness [mm] Filter Sections [m] CG / CG CG / / / CG CG-06/ / Drill hole collar information and filter sections of completed drill holes

19 Test drilling After the drilling, putting casing in place Finalized drilling with casing and Flag of the project Drilling rig at the hole nr. 1 Drilling machine with water basin left

20 Lab testing of drill samples More than 100 samples of coal and surrounding rock strata taken from drill core for lab testing in Greece (CERTH) and Germany (DMT) Analyses on quality, petrography and mechanical properties of coal Analyses on geomechanical parameters on roof and floor strata of target seams (V, VI VII and VIII) and of surrounding strata

21 Logging of test drills Geophysical well logging Geological and geotechnical core logging

22 Logging of test drills Pumping tests Water monitoring (online) 360 scan of lignite core Topographic survey DMT CoreScan

23 Logging of test drills Seam IX Seam VIII Seam VI VII Seam V Seam IV

24 UCG Panel and Well Design & Engineering Well configurations 3types of UCG module configuration that are similar: they all require a minimum of an injection well to inject the oxidizing agents and start ignition, and a production well to recover the syngas. Linked Vertical Well (LVW) standard configuration the process wells comprise at least two vertical wells drilled into the coal seam. The injection point is located at the base of the vertical injection well and the production point at the base of the vertical production well. The Enhanced (or extended) Vertical Well configuration (E LVW or ELW) is very similar to the LVW but uses a deviated in seam borehole to link the two vertical wells. Linear Controlled Retracting Injection Point (L CRIP) configuration a L CRIP module comprises a deviated injection well drilled along the base of a coal seam and linked to a vertical production well. Parallel Controlled Retracting Injection Point (P CRIP) configuration in the P CRIP configuration, both process wells are deviated and drilled in seam parallel to each other. Steeply Dipping Bed (SDB) configuration has been used in coal seams with high dip angle (>60 ). It comprises two slanted process wells: the production well is drilled in seam to a predetermined distance above the base of the injection well, which is drilled initially beneath the coal seam until it intersects the coal seam.

25 Major UCG projects Name Funded Place Years Rank ASTM (1) Depth (2) Major UCG projects in the USA (UNERBEL, 2014) Hanna series (1 to 4) US Government Wyoming 1) ; 2) ; 3) 1977; Low Shallow 4) Hoe Creek (1 to 3) series US Government Wyoming 1) 1976; 2) 1977; Low Shallow 3) 1979 Princetown US Government West Virginia 1979 Medium Intermediate Rawlins series (1 to 2) plus CCUCG 1) 1979; US Government Shallow Wyoming 2) 1981; Low CCUCG: private Intermediate CCUCG: Centralia Large Blocks Tono 1 US Government Washington Low Shallow Rocky Mountain I (Tono 2) US Government Wyoming Low Shallow Major UCG projects in USSR (UNERBEL, 2014) Podmoskovna USSR Russia Low Shallow Lisichansk USSR Russia Medium Shallow Schatsky USSR Russia Low Shallow Juschno Abinsk USSR Siberia From 1955 (end?) Intermediate Shallow Angren USSR now private: LINC Uzbekistan From 1962 (still in activity?) Low Shallow

26 Major UCG projects Name Funded Place Years Rank ASTM (1) Depth (2) Major UCG projects in Europe (UNERBEL, 2014) Newman Spinney series UK England Low Shallow Djérada France Morocco High Shallow Haute Deule France and EU France High Deep Bois la Dame Belgium Belgium 1948 High Shallow Thulin Belgium, Germany and EU Belgium High Deep El Tremedal Spain, Belgium, UK and EU Spain Low Intermediate Major UCG projects in Australia, Canada and South Africa (UNERBEL, 2014) Linc series (1 to 5) Private Queensland, AU Low Shallow Cougar Private Queensland, EU 2011 Low Shallow Carbon Energy series (1 to 2) Private Queensland, EU Low Shallow Swan Hills Alberta Innovates, Private Alberta, CA Intermediate Deep Majuba Private South Africa N.A. Low Shallow Notes: (1) Low: Lignite to subbituminous; Medium: Bituminous; High: Anthracite (2) Shallow <300m; Intermediate >300m; Deep >800m

27 Well configuration selected for Urdari Based largely on the results of previous trials, particularly the RM 1 trial (Wyoming, USA), and recent developments in drilling, borehole completion and survey technologies, it was concluded that L CRIP was the optimum UCG module configuration for the Oltenia coalfield

28 Well design & engineering for integrity and safety In the targeted area of the Urdari site, four coal seams were identified suitable for UCG: (i) the coal seam X (ii) the coal seam VIII, (iii) the coal seam VI, and (iv) the coal seam V. The shallow coal seam VIII was considered as the basic study case and the deeper coal seam V was considered as the optional study case.

29 Guidelines for the well design & engineering Guidelines for the well design and engineering applicable to the four preselected site locations in Oltenia have been developed with focus on Urdari the site selected for test drilling. The guidelines are: Definition of stratigraphic units (and sub units, if necessary) Definition of phases (and sub phases, if necessary) Definition of well configuration and well positioning (3 types of wells) Aspects of reactor to be considered Aspects of the design to be considered (per type of well) Well control and monitoring techniques (per type of well) Based on these guidelines, the pilot scale well pre design and engineering was developed with the focus on operational integrity, post operational abandonment, and others technical issues and monitoring techniques. The pre design was adapted to the specific conditions of the Urdari selected site.

30 Risk assessment framework for UCG The FEP method was chosen to assist the RA. FEP stands for Features, Events and Processes. Common approach for risk assessment: the risk matrix combining the severity and likelihood of an event Phase (1): Expert questionnaire: isolated Phase (2): Expert workshop Work plan Interrelations between the FEPs Phase (3): Carry out work plan Defined knowledge gaps, modeling, reduce uncertainties Phase (4): Decision making, feasibility, go/nogo Risk Assessment approach (green = low risk, acceptable; yellow = moderate risk, possibly acceptable, red = high risk, not acceptable) severity x likelihood = risk of an event

31 Database with risk factors Existing risk databases for related topics (such as CO 2 storage) have been screened. A list of FEPs has been compiled. In order to construct an inventory the FEPs (preliminary) were organized in three groups: FEPs related to site specific basic geo scientific knowledge regarding the host rock FEPs related to interaction between UCG or UCG related activities and host rock FEPs related to economic issues The database was organized according to the phases in a UCG project: Construction (or preparatory) phase Operational phase Post operational phase (until decommissioning) Post Decommissioning phase (some monitoring might continue after decommissioning)

32 Assess the calculated risks on the basis of legal requirements A risks legal requirements matrix has been constructed on the following structure: specific risks that could occur during: construction phase operation phase post operation phase decommissioning phase risk assessment, including general FEP (features, events & processes), level of impact (minor, moderate, major) and probability range (low, medium, high) The matrix has been filled with recommendations for the design of a potential future UCG pilot project in Romania in terms of: : legal Romanian requirements and EU legislation; treatment of residual risks.

33 Site specific proposal for syngas utilization Use of syngas in industrial facilities for the chemical sector Use of syngas for fueling residential consumers in the surrounding area Use of syngas by CEO in the existing power plants facilities instead of natural gas as additional fuel Use of syngas on site in a new facility (gas engine) for electricity generation Syngas cost vs. natural gas price for alternatives 1 and 2 Simplified cost benefit analysis (CBA) for alternatives 3 and 4

34 Conclusions Coal industry is struggling; during the past years, a significant number of mines have been closed in Romania, due to their economic inefficiency and the old technologies. UCG can access and exploit those resources that cannot be mined economically with other technologies and has the potential to provide cleaner energy than direct combustion of coal in power plants. The COAL2GAS project brings together research teams and industrial actors from most of the main lignite producing countries in the EU The tests and experiments performed during the COAL2GAS projects represent the most recent detailed analyses on Romanian lignite and are the starting point in estimating whether a UCG pilot can be implemented in Romania with focus on safe and environmentally friendly operations.

35 Thank you for your attention! Contacts