Roman Zarzycki

In-vessel composting for utilizing of municipal sewage-sludge

The amount of sludge generated from wastewater treatment plants has been increasing year-by-year as the sewerage service area expanded. The composting process is considered to be one of the best management methods to stabilize different organic wastes. The main goal of this investigation was to find the optimal ratio of the quantity of the organic waste to the quantity of the sewage sludge. The process of composting was carried out in the Horstmann bioreactor (pilot scale) for 2-3 weeks and then in a compost pile for 6-12 weeks. Seven experiments were performed, with different ratios of the quantity of organic wastes to the quantity of sewage sludge. The results enabled an estimation of the quality of compost and its usefulness and also the usefulness of the bioreactor to be deduced.

Adsorption of Cr(VI) on Cross‐Linked Chitosan Beads

Abstract A possibility of Cr(VI) removal by the adsorption method is discussed in the paper. An adsorbent were hydrogel chitosan beads are produced by the phase inversion method (by changing pH). The possibility of removing Cr(VI) ions by both pure chitosan hydrogel and its chelate compounds (chitosan cross‐linked with Cu(II) and Ag(I) ions) was investigated. The adsorption proceeded from the solutions of potassium dichromate and ammonium dichromate (NH4)2Cr2O7 and K2Cr2O7. The process rates and adsorption isotherms were determined and described by relevant equations. The process rate was described by the pseudo‐ and second‐order equations, and adsorption equilibria by the Langmuir equations. A slight advantageous change in adsorption properties of chitosan beads was revealed after cross‐linking (for chromium concentration up to 10 g/dm3). A maximum adsorption was 1.1 gCr/g chitosan. Results of the studies show that chitosan hydrogel proves useful in the removal of Cr(VI) ions, additionally, cross‐linking with Cu(II) and Ag(I) ions has an advantageous effect in the case of low‐concentrated solutions.

The Effect of Chitosan form on Copper Adsorption

Adsorption of Cu ions in hydrogel and dried chitosan beds is described in this paper. Adsorption isotherms are determined and process rates are presented. For comparison, the complexing ability of a chitosan salt in the form of chitosan acetate is determined. The highest adsorption abilities are revealed by a hydrogel chitosan bed.

How far is environmental engineering from biomedical engineering

Abstract The development of science, which has been observed in recent years, shows that engineering knowledge and activity are becoming more and more interdisciplinary. Up to the late 80-ties of the previous century, the experience and interest of engineers covered mainly hard sciences that directly followed their education. After this period, the engineering knowledge and solutions proposed in one discipline started to be applied successfully in other domains. This tendency can be seen especially in Biomedical Engineering, which development is based on achievements made in the rest of hard sciences, even if they seem to be as distant as Environmental Engineering.

How to change a shrimp into an intelligent drug carrier

Design of hybrid systems (structures composed of a carrier and pharmacological agent) for controlled release inside the body is a major direction in creation of new forms of drugs. These novel drug carriers should possess better accessibility and effectiveness with limited side-effects. The main purpose of this study was to construct a new form of chitosan carrier with the ability to transform from sol to gel at the physiological temperature of human body. Controlled drug release systems were formed by mixing b-sodium glycerophosphate with the solutions of chitosan glutaminate.

Chapter 10 – INTRODUCTION TO THE DESIGN OF ABSORBERS

gases in ammonia production. Another example is the removal of all acid gases from natural gas to meet the gas specification. These processes can be performed either by physical or chemical absorption. Sometimes, however, although there are several active components in the gas, only one of them is to be absorbed completely. This process is called selective absorption. In these processes differences in gas solubilities or reaction rates in liquids for particular components of the gas mixtures are utilized. ii) The other aim of absorption is to obtain a particular component in the liquid phase. As a result of absorption of one or more gases and the chemical reaction which takes place in the liquid, the desired chemical compound is obtained. Sometimes the chemical reaction may occur in the presence of solid catalysts. An illustration of a process without a catalyst is SO^ absorption in

Chapter 7 – SIMULTANEOUS MASS TRANSFER WITH CHEMICAL REACTION

1) Mass transfer and chemical reaction occur consecutively: one process follows the other. First, mass transfer of several components takes place, then a chemical (biochemical) reaction follows, and next mass transfer of these or other components occurs again. All these processes take place in the same equipment. An illustration is a catalytic reaction in which substrates (components A, B , . . . , F) must first diffuse into the active centres of a catalyst, and then a chemical (biochemical) reaction takes place on the catalyst surface. After the reaction, the remaining products (other components Η,. , . ,Κ) diffuse from the catalyst surface to the liquid bulk. Each partial process has its own driving force. In a steady state the rates of partial processes must be equal, which in the case of first-order linear processes allows us to use one driving force. This type of process can be presented schematically as in Fig. 7-1.