Presentation on theme: "Tot siens? Of nie?. CBM = Coal Bed Methane A. Will the Springbok Flats survive the exploration for it and the production of it? B.Will the people of the."— Presentation transcript:
CBM = Coal Bed Methane A. Will the Springbok Flats survive the exploration for it and the production of it? B.Will the people of the Springbok Flats allow it?
The answers to these questions need to be informed by what we consider as responsible interaction between man and the ecology. Should we allow ourselves to be the aggressors on the natural resources that have the capacity to sustain our livelihood, provided we use it judiciously?
What is this thing, Methane? A valuable source of energy = a fossil fuel! Derived of micro-organisms acting on ancient biomatter.
Providing oxygen to Methane creates a combustible mix!
Burning Methane unfortunately produces CO 2. Just like burning coal does. Once ignited, Methane produces energy and two new molecules.
Man and his environment are interdependent entities. The sustainability of this system depends ultimately on the choices man makes. The relationship between man and the environmental phenomena is characterised by the socio-economic expectations man has for his day-to-day livelihood. The higher man’s living standard the higher is the impact on Planet Earth’s resources.
It is all around us and has amazingly different origins Methane is not scarce!
Our world has a growing need for more energy to keep the wheels turning for 7,2 billion people. One form of energy presents itself in the form of Springbok Flats Methane. The problem is that we live on top of it and that it needs agressive impacts on the environment to get to it in order for it to work for us! The question is, how are we to balance our needs and the needs of the natural environment with the needs of the fuel industry?
Coal Bed Methane is natural gas trapped in coal seams underground. To extract the gas, after drilling into the seam, it is necessary to pump large amounts of water out of the coal seam to lower the pressure. It is often also necessary to frack the seam to extract the gas. This results in methane migration, toxic water contamination, air pollution, increased carbon emissions and a general industrialisation of the countryside. Impacts that are specific to CBM include depletion of the water table and potentially subsidence. Next
How Is CBM extracted? Within coal beds Methane is contained in solution and on cleat surfaces and is held in place by hydraulic pressure. To develop these unconventional gas resources, Coal-bed Methane projects involve the dewatering of coal beds which result in the production of gas at the surface. Lowering of the hydraulic pressure by withdrawal of water from wells completed in the coal-bed, allows the Methane to be released and recovered. Coal-bed Methane projects typically cover large areas of land with producers drilling hundreds of wells. Horizontal drilling is used to reduce the impact of land access issues. Development of Coal-bed Methane resources generally involves five phases: Phase I General exploration involving identification of coal-area, characterization of coal (rank, thickness, extent, depth of coal-seam etc.), identification of suitable areas for drilling; and core drilling and testing for gas content, gas saturation and permeability of the coal. Phase II Geology, geophysics and geohydrology. Phase III Pilot project to determine the economic viability of a site. Project economics are determined by a number of factors: well flow rates, well spacing, cost of drilling and development, developing costs, ability to dispose of water cheaply, good land access and market access. Phase IV Phased development Phase V Abandonment, with or without rehabilitation.
Conventional gas = highest; Coal-bed CBM = less; Tight gas = even less; Gas shales = lowest Hydrocarbon traps will differ in permeability:
Methane Storage in Coal Coal serves as both the source rock and the reservoir rock. Hydraulic pressure, rather than a pressure seal or closed structure (common for conventional oil and gas fields), is the major trapping force for CBM. Coal is extremely porous but has low permeability (connected openings). Gas storage in coal beds is more complex than in most conventional reservoirs. Coal contains unique properties for gas storage that are not present in other reservoirs. Coal-bed Methane is stored in four ways: 1) as free gas within the micropores and cleats (natural fractures in the coal); 2) as dissolved gas in water within the coal; 3) as absorbed gas held by molecular attraction on surfaces of macerals (organic constituents that comprise the coal-mass), micropores, and cleats in the coal; and 4) as absorbed gas within the molecular structure of the coal molecules.
The quality of a reservoir rock is determined by its porosity and its permeability In some cases most of the CBM gas is adsorbed on the surface of the coal. Pumping to release the pressure is here one option.
But before you can start pumping, you have to master the world of pressure control drilling. If not, a surface blow-out will surely get your attention!
NOT huge, continuous "pools" of gas but rather minuscule pores between the grains with CBM that make up the rock matrix = "reservoir rock “. The real world is however not this simple: underneath and on top! Made simple!
Successful and simple pumping depends mostly on sufficient saturation: That is the percentage of sediment pore space in the source rock occupied by gas hydrate. 1.What about contamination on top and beneath the surface by pumping? 2.What about cross contamination between aquifers? What if the gasbearing coal layer is too consolidated and unpermeable and will require gas flow to be stimulated? 1.One possibility to achieve this is to FRACK. 2.The other option is CAVITATION. What if the presence of Uranium and Radon endangers safe extraction, production and use? What if safe separation of the Uranium/Radon complex from the Methane/coal is not econmically viable at production scale ?
CBM “produced water” is to be managed through some combination of treatment, disposal, storage, or use, subject to compliance with DWA regulations.
One way to get rid of CBM “produced water” ARID = Aquifer Recharge Injection Device ARID tool in the well-bore above the coal-seam, shows pumping the water from the coal-seam to a shallower aquifer that contains water of similar quality, but presents the real threat of cross aquifer contamination. http://www.bigcatenergy.com/CBM-Environmental-Issues.aspx NB! Aquifers differ in salinity and other chemical qualities.
Grouting while drilling? Afterwards is too late!
Hydraulic fracturing is used as a primary means of stimulating gas flow in CBM wells. Another gas stimulation technique, unique to CBM wells, is known as cavitation (also known as open-hole cavity completion). Cavitation is a similar phenomenon to opening a shaken pop bottle, only on a much larger scale. Water, and air or foam are pumped into the well to increase the pressure in the reservoir. Shortly thereafter, the pressure is suddenly released, and the well violently blows out, spewing gas, water, coal and rock fragments out of the well. This action is sometimes referred to as "surging", and it is accompanied by a jet engine-like noise, which can last up to 15 minutes. http://www.energyjustice.net/naturalgas/cbm
What are the challenges to produce CBM by stimulating gas flow? Order Disorder! What are the options? What are the downsides? 1.Fracking: NEEDS A BIG LOT OF WATER PLUS LOTS OF CHEMICALS 2.Cavitation: NEEDS A LOT OF WATER PLUS CHEMICALS 3.Pumping:DISTURBS AQUIFER BALANCE; CREATES CROSS-CONTAMINATION OF AQUIFERS. GAS LEAKS AND CONTRIBUTES TO AIR POLLUTION. Is it sustainable? Do we want it? Will our area’s socio-economic fabric survive it? If dewatering stops, the coal seam and the well fill with water, which automatically prevents the gas from being released.
Forever Resorts – Possible sources of heat The water issuing from a hot spring is heated by geothermal heat, i.e. heat from the Earth’s mantle. In general, the temperature of rocks within the earth increases with depth. The rate of temperature increase with depth is known as the geothermal gradient. If water percolates deeply enough into the crust, it will be heated as it comes into contact with hot rocks. The water from hot springs in non- volcanic areas is heated in this manner. Warm springs are sometimes the result of hot and cold springs mixing but may also occur outside of volcanic areas, such as warm springs. Should we allow anybody to “play” around Bela-Bela’s hot spring?
Aerial view of the Jonah natural gas field, upper Green River Valley, Wyoming, 2001 - SkyTruth CBM development has a huge "footprint" on the landscape and the process used to extract Coal-bed Methane depletes local aquifers, causing groundwater levels to drop and wells to run dry. The accumulation of Coal-bed Methane wells and associated compressor stations, service roads, power lines and related infrastructure fragments bushveld habitat, harms wildlife, and the ecology as well as the sense of place and the socio-economic fabric. http://www.sagebrushsea.org/threat_energy_development.htm
http://www.alandoutoftime.com/mediaresources.html A close-up view you can smell!
Só sal dit oor ‘n paar jaar vanaf Buyskop lyk – as ons nie wakker loop en vasstaan nie.
Coal Bed Methane: The Evil Twin of Shale Gas In common with other unconventional gas extraction, such as Shale Gas, CBM wells do not produce large amounts of gas per well and production declines very quickly. It is therefore necessary to drill large numbers of wells, covering huge swathes of the landscape. CBM exploitation began in the US and over 55 000 CBM wells have been drilled in the last decade or so, mostly in the western states (Colorado, New Mexico and Wyoming in particular). In Australia, where it is known as Coal Seam Gas (CSG), over 5 000 CBM wells have been drilled in Queensland in the last few years and the industry is aggressively expanding into New South Wales. In the UK CBM is more advanced than Shale Gas and full-scale production may begin soon. Over 44 percent of wells are leaking in an Australian gas field overseen by UK Treasury director Baroness Hogg.
Aerial view of the Jonah natural gas field, upper Green River Valley, Wyoming, 2001 - SkyTruth Kyk weer!
Simply pumping depends mostly on sufficient saturation: That is the percentage of sediment pore space in the source rock occupied by gas hydrate. 1.What about contamination on top and beneath the surface by pumping? 2.What about cross-contamination between aquifers? 3.What about leaking gas and air contamination? What if the gasbearing coal layer is too consolidated and unpermeable and will require gas flow to be stimulated? 1.One possibility to achieve this is to FRACK. 2.The other option is CAVITATION. What if the presence of Uranium and Radon endangers safe extraction, production and use? What if safe separation of the Uranium/Radon complex from the Methane/coal is not economically viable at production scale ?
Finally... A. Will the Springbok Flats survive exploration for CBM and the production of it? B.Will the people of the Springbok Flats allow it?
We have the Constitutional right to oppose it! We no longer have to practise this in a vacuum because The Bill of Rights of our Constitution since 1996 provides as follows in regard to the environment: 24Everyone has the right a. to an environment that is not harmful to their health or well-being; and b. to have the environment protected, for the benefit of present and future generations, through reasonable legislative and other measures that i. prevent pollution and ecological degradation; ii. promote conservation; and iii. secure ecologically sustainable development and use of natural resources while promoting justifiable economic and social development.
vir dit? http://beyondeconomics.files.wordpress.com/2013/01/fracking-field-4.jpg
Kom help dat ons kan saambou aan die insig om ons gebied gesond te hou en om ons te help om vas te staan om CBM-produksie en ander myne in hierdie gebied af te wend. By understanding how to keep our area healthy we will gain the knowledge to remain steadfast against wilful destruction.
En wat nou as die oopgroef Uraan- en Steenkoolproduksie voortgaan? Nog erger as met CBM...... is hoe die oopgroefmyne sal lyk. Hier is een van die groot getal oopgroefmyne by Middelburg/Witbank!