Mathematical model of washing of filtration cake

The issue of this article is one stage washing of reaction blend after enzyme hydrolysis under which we are able to recycle almost all contained chromium in solid leather waste. During hydrolysis we gain protein hydrolysate as a filtrate that is appropriate substance for use. On the basis of equation for streaming of liquids through layer of substance we determined optimal pressure differential for filtering and washing of reaction mix and we applied mathematical description valid for filtering and one stage washing and on the basis of this models we able to optimize washing process that is add to filtering and which aim is to reduce content of protein hydrolysate in filter cake

Modeling of the ecological separation process of printed circuit boards

The content of this paper is the modeling of the stress in the printed circuit board due to the cyclic thermal stress for its ecological recycling. Cyclic thermal stresses result in separation of copper conduction paths and plastic plates due to different longitudinal expansion. For separation, it was important to determine the minimum temperature of the cyclical changes to separate the conductive copper paths and the plastic. We use mathematical modeling tools to describe the course of temperature fields in the PCB during heating and reheating. We conducted some simulation experiments in the Pro/ENGINEER programming environment to know the waveforms and stresses of the PCBs during the cyclic loading cycle. From experiments conducted in the laboratory, we have verified that the process of temperature separation is feasible for designing an eco-friendly way of recycling PCBs. © 2018 The Authors, published by EDP Sciences.Slovak Research and Development AgencySlovak Research and Development Agency [APVV-15-0602]; Ministry of Education, Youth and Sports of the Czech RepublicMinistry of Education, Youth & Sports - Czech Republic [LO1303 (MSMT-7778/2014)]; European Regional Development Fund under the project CEBIA-Tech [CZ.1.05/2.1.00/03.0089