Preliminary Research On Determining Behavior Parameters Of Ethanol And BTEX In Porous Media By Temporal Moment Method

Monoaromatic hydrocarbon such as benzene, toluene, ethylbenzene, xylene and its isomers (refer as to BTEX) included gasoline has been concerned thoughout the world as contaminations. It is possible be polluted by these materials in a certain degree of influence, but this pollution-related cases are seldom reported in our country.In order to interpret these contaminations transport and fate, a sand aquifer tank in the laboratory was set up, then put into contaminations such as gasoline saturation solution containing ethanol with tracer (Bromide) and gasoline saturation solution with tracer (Bromide), monitor the contamination's concentration change with time, create database and so on. Then, temporal moment is used to computer these contamination's transport behavior parameters. Compared to these behavior parameters, and get some conclusions as follows:1, In the sand aquifer model, BTEX flow rate is less than the migration rate of water for free-ethanol gasoline contaminants; The diffusion coefficient of BTX in the aquifer between 0.0050 m2/d and 0.0056 m2/d; TEX degradation could inhibit the degradation of benzene and accelerated the diffusion of benzene in the aquifer in the process at the same time ; Also be showed from these parameters of monoaromatic hydrocarbon first-order degradation rate constant as following:λT>λE>λm+p-X>λo-X≈λB;2, In the sand aquifer model, BTEX flow rate is less than the migration rate of water and ethanol ; The diffusion coefficient of BTEX in the aquifer between 0.014 m2/d and 0.025 m2/d, except for ethanol which diffusion coefficient is 0.0033 m2/d; Compared to the diffusion coefficient of BTEX and ethanol, we can show ethanol as solvent as water only. Also, ethanol and BTEX first-order degradation rate is in the order:λEt-oh>λT>λE>λm, pX>λo-X≈λB.3, Compared to the two tracer tests as show: In the sand aquifer model, the flow rate of BTEX which contain ethanol are amplified ,and these flow rate are greater than the test which the ethanol-free, the first-order degradation rate(except m+p-X) are greater at the same time, the diffusion coefficient of BTEX are greater than the test which ethanol-free. So the ethanol simulate BTEX moving, and ethanol can be called lubricant.4, The Thermal Decay of software simulation found that the aquifer is relatively homogeneous; The flow rate and retardation coefficient keep with calculation of temporal moment.From the experiment, the behavior parameters of the contaminations(BTEX) are accurate fitted and the influence of the ethanol is seen by these parameters which can provide a basis of scientific, while the parameters are good at safety of water resource for protection.