Friday, December 6, 2019
Carbon Sequestration free essay sample
CO2 can also be transported as a liquid on road tankers or railcar in insulated tanks at low temperature and by ships where CO2 has to be moved over large distances or overseas. Injection and Storage (State of the gas when stored) it is injected as a supercritical fluid (dense and liquid-like) at sufficiently high pressures and temperatures through an injection well into the target reservoir formation, generally at a depth of 800m or more. A reservoir rock could be sandstone, in which the CO2 is stored in the microscopic pore spaces between individual sand grains. In this case, we need to consider better CO2 injections technologies and CO2 injection wells have to ensure that CO2 only enters the intended injection zone and does not interfere with sources of drinking water. Types of rocks Suitable rocks for storage are generally high porosity type to provide space for the CO2 and high permeability for the CO2 to move into the space. We will write a custom essay sample on Carbon Sequestration or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page By contrast, the seals covering the storage formation typically have low porosity and permeability to trap the fluids stored below. Injectivity is also important as the rate at which the CO2 can be injected into a storage reservoir formation. Geological condition Three types of geological formations to be considered for the storage of CO2 are oil and gas reservoirs, deep saline formations and deep un-minable coal seams. Storage sites must generally be located at a depth of 800m or deeper where prevailing pressures keep CO2 in either a liquid or supercritical state so that CO2 is trapped without moving back up to the surface. Deep Saline Formations (Geological condition and natural process) It takes place at depths below 800m where the ambient pressures and temperatures will usually result in CO2 being in a liquid or supercritical state. At these conditions, there is some buoyant forces that tend to drive CO2 upwards so that we have to make sure having a well-sealed cap rock over the storage reservoir that remains CO2 trapped in underground. Sequestration of CO2 in deep saline formations does not produce value-added by-products, but it has other advantages.