Search Results

1 - 6 of 6 items

  • Author: Zbigniew Suchorab x
Clear All Modify Search
Influence of Treated Sewage Discharge on the Benthos Ciliate Assembly in the Lowland River

Abstract

This paper presents results of the studies of ciliate assemblage in benthos of lowland river influenced by sewage discharged from the municipal wastewater treatment plant. During the presented research the 47 ciliate species, including 45 species from the benthos of the river and 18 from the activated sludge of aeration chamber were identified. Only two species registered in the activated sludge were not observed in the river. Against the background of the lowest number of species in the point located in the distance of 50 m below the discharge of sewage the maximum amount and biomass of these species were observed. Whereas, 200 m below the discharge the decrease in number and biomass of ciliate to the level noted for location before the discharge was observed. Thus, generalizing, one may state that influence of municipal WWTP sewage discharge for ciliate assemblage in the river’s benthos was clearly visible but local.

Open access
Methodology of Moisture Measurement in Porous Materials Using Time Domain Reflectometry / Metodyka Prowadzenia Badań Wilgotności W Ośrodkach Porowatych Za Pomocą Reflektometrii W Domenie Czasu

Abstract

The article presents the description of measurement methodology of moisture transport in unsaturated porous materials using Time Domain Reflectometry (TDR) technique on the example of measurement of capillary uptake phenomenon in the sample of autoclaved aerated concrete (AAC). In the paper there are presented basic principles of the TDR method as a technique applied in metrology, its potential for measurement of moisture in porous materials like soils and porous building materials. Second part of the article presents the experiment of capillary rise process in the sample of AAC. Within the experiment moisture content was monitored in the sample exposed on water influence. Monitoring was conducted using TDR FP/mts probes. Preparation of the measuring setup was presented in detail. The TDR readouts post-processing, graphical presentations of the obtained results, short discussion and comparison of TDR readouts to gravimetric measurement were also presented.

Open access
Suitability of combined sewers for the installation of heat exchangers

Abstract

The present paper deals with the classification of the suitability of combined sewers for the installation of heat exchangers and with assessment of the theoretical potential of wastewater in the sewer system for heating of buildings. A classification scheme involving criteria like theoretically available heat, sewer diameter, number of the heat exchanger parallel modules in the sewer cross-section, hydraulic conditions (hydraulic capacity of the sewer, pressurized flow), and potential fouling by biofilm growth was developed. First, individual sewers in the pilot catchment were assessed based on monitoring the flow characteristics and wastewater temperatures and on pipe flow modelling. Second, connectivity of the suitable and partly suitable sewers was examined with respect to the length necessary for the installation of the heat exchanger with the minimum required power of 100 kW. For the continuous sewer sections, the maximum potential power was calculated. The presented approach is generally applicable, however, for other heat exchanger types and other climatic and economic conditions, values of the suitability criteria for the heat exchanger installation must be adapted.

Open access
Free of Volatile Organic Compounds Protection against Moisture in Building Materials/Zabezpieczenia Przegród Budowlanych Przed Wilgocią Wolne Od Lotnych Związków Organicznych

Abstract

The article presents information about moisture protection of building materials. The discussed parameters determining the efficiency of the water protection are material porosity, water absorptivity and surface condition of building materials. Moreover the ecological aspect of hydrophobic VOC-free preparations available on the market has been underlined. The first part of the article is a description of moisture problem in the building envelopes and the possibilities of its prevention. The special attention is put on the electric methods of moisture estimation with a special emphasis on the Time Domain Reflectometry (TDR) method. The second part of the article is devoted an experiment of model red-brick walls exhibited on capillary uptake process. For the experiment three model red-brick walls were built and prepared for water uptake process. The experiment was monitored by the capacitive and surface TDR probes thanks to which the necessity of sampling and material destruction could be avoided. Conducted experiments show the progress of water uptake phenomenon in the model walls which differ in type of protection against moisture and prove the potential of the non-invasive measurements using the surface TDR probes. Basic physical parameters of the applied bricks were determined together with the reflectometric measurements. Furthermore, Scanning Electron Microscopy (SEM) was used to analyze the hydrophobic layer continuity.

Open access
The Possibility of Utilization of Sewage Sludge as a Filler in Production of the Lightweight Aggregate Concrete

Abstract

The article presents the laboratory investigations of the basic thermal and hygric parameters of standard lightweight aggregate-concrete and lightweight aggregate-concrete supplemented with municipal sewage sludge. Both types of concrete are based on light aggregates, commonly used in the Polish building market. In order to improve the hygric parameters of the material, such as water absorptivity, the admixture of water emulsion of reactive polisiloxanes was applied. Within the presented research, together with basic moisture parameters estimation, capillary rise process was monitored using Time Domain Reflectometry (TDR) modified sensors. Hygric parameters were supplemented with the estimation of thermal conductivity coefficient λ determined using stationary method. The analysis of thermal and hygric properties of concrete confirmed the applicability of lightweight aggregate-concrete with sewage sludge supplementation for further production.

Open access
Evaluation of the Contact Angle of Hydrophobised Lightweight-Aggregate Concrete with Sewage Sludge

Abstract

The aim of the research presented in the paper was to evaluate the feasibility of using hydrophobic preparations based on organosilicon compounds for protection treatment of lightweight aggregates modified with municipal sewage sludge. Issues related to the wettability of the surface layer of hydrophobised lightweight-aggregate concrete supplemented with sewage sludge are discussed in the paper. The experimental part of the study is focused on the physical and mechanical characteristics of lightweight-aggregate concrete and the effect of two hydrophobic preparations on the contact angle of the material. The contact angle for lightweight concrete (θw) was determined as a function of time using one measurement liquid. The hydrophobic coatings in the structure of lightweight concrete modified with sewage sludge were shown using electron microscopy. The investigations demonstrated the effectiveness of hydrophobisation of porous lightweight concretes. On the hydrophobic surfaces, the contact angles decreased with time and depended on the preparations used. The results of the research confirm the possibility to produce lightweight aggregate-concretes modified with sewage sludge with appropriate surface protection against external moisture.

Open access