The filtration coefficient before filtration (λ-0)is intro-duced and a mathematical model for the leukocyte filtra-tion process, which relates to the filtration efficieney,capacity and leukoeyte concentration, filter...The filtration coefficient before filtration (λ-0)is intro-duced and a mathematical model for the leukocyte filtra-tion process, which relates to the filtration efficieney,capacity and leukoeyte concentration, filter thickness and fliter surface area, is established according to the mass balance for particles in a filter and the particle concen-tration decrease per unit of filter depth. The model can be uded to calculate the filtration efficiency or capacity.It is found that the filtration performance observed dur-ing the experiments could be explained well by the mod-el.The established model can be applied to the design and optimization of ungrafted and grafted melt blown nonwoven filtration materials.展开更多
Transport of suspensions and emulsions in porous media occurs in numerous processes of environmental, chemical, petroleum and civil engineering. In this work, a mass balance particle transport equation which includes ...Transport of suspensions and emulsions in porous media occurs in numerous processes of environmental, chemical, petroleum and civil engineering. In this work, a mass balance particle transport equation which includes filtration has been developed. The steady-state transport equation is presented and the solution to the complete advective-dispersion equation for particulate suspension flow has been derived for the case of a constant filter coefficient. This model in-cludes transport parameters which are particle advective velocity, particle longitudinal dispersion coefficient and filter coefficient. This work recommends to be investigated by particle longitudinal dispersion calculation from experimental data, directly. Besides, the numerical model needs to be developed for general case of a transition filter coefficient.展开更多
Deep bed filtration of carrier water with particles occurs in numerous processes of environmental, chemical, petroleum and civil engineering. For example in the petroleum industry, deep bed filtration of drilling flui...Deep bed filtration of carrier water with particles occurs in numerous processes of environmental, chemical, petroleum and civil engineering. For example in the petroleum industry, deep bed filtration of drilling fluid happens during well drilling;it also takes place near to injection wells during seawater injection or produced water re-injection causing in- jectivity reduction. In this work, the filtration theory and its mathematical model are given and the filtration coefficient will be discussed. Then the transition time, the time at which the initial layer of external filter cake is completely formed has been derived mathematically. The transition time can be obtained by calculating the trapping efficiency as a function of the number of previously deposited particles where very few particles can invade the rock and the external filtration begins to build. The prediction of particle capturing and particle retention by mathematical model is an essen- tial stage during planning and design of above-mentioned industrial processes.展开更多
文摘The filtration coefficient before filtration (λ-0)is intro-duced and a mathematical model for the leukocyte filtra-tion process, which relates to the filtration efficieney,capacity and leukoeyte concentration, filter thickness and fliter surface area, is established according to the mass balance for particles in a filter and the particle concen-tration decrease per unit of filter depth. The model can be uded to calculate the filtration efficiency or capacity.It is found that the filtration performance observed dur-ing the experiments could be explained well by the mod-el.The established model can be applied to the design and optimization of ungrafted and grafted melt blown nonwoven filtration materials.
文摘Transport of suspensions and emulsions in porous media occurs in numerous processes of environmental, chemical, petroleum and civil engineering. In this work, a mass balance particle transport equation which includes filtration has been developed. The steady-state transport equation is presented and the solution to the complete advective-dispersion equation for particulate suspension flow has been derived for the case of a constant filter coefficient. This model in-cludes transport parameters which are particle advective velocity, particle longitudinal dispersion coefficient and filter coefficient. This work recommends to be investigated by particle longitudinal dispersion calculation from experimental data, directly. Besides, the numerical model needs to be developed for general case of a transition filter coefficient.
文摘Deep bed filtration of carrier water with particles occurs in numerous processes of environmental, chemical, petroleum and civil engineering. For example in the petroleum industry, deep bed filtration of drilling fluid happens during well drilling;it also takes place near to injection wells during seawater injection or produced water re-injection causing in- jectivity reduction. In this work, the filtration theory and its mathematical model are given and the filtration coefficient will be discussed. Then the transition time, the time at which the initial layer of external filter cake is completely formed has been derived mathematically. The transition time can be obtained by calculating the trapping efficiency as a function of the number of previously deposited particles where very few particles can invade the rock and the external filtration begins to build. The prediction of particle capturing and particle retention by mathematical model is an essen- tial stage during planning and design of above-mentioned industrial processes.
