38 research outputs found

    Differences in stress tolerance and brood size between a non-indigenous and an indigenous gammarid in the northern Baltic Sea

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    Differences in stress tolerance and reproductive traits may drive the competitive hierarchy between nonindigenous and indigenous species and turn the former ones into successful invaders. In the northern Baltic Sea, the non-indigenous Gammarus tigrinus is a recent invader of littoral ecosystems and now occupies comparable ecological niches as the indigenous G. zaddachi. In laboratory experiments on specimens collected between June and August 2009 around Tva篓rminne in southern Finland (59掳500N/23掳150E), the tolerances towards heat stress and hypoxia were determined for the two species using lethal time, LT50, as response variable. The brood size of the two species was also studied and some observations were made on maturation of juveniles. Gammarus tigrinus was more resistant to hypoxia and survived at higher temperatures than G. zaddachi. Brood size was also greater in G. tigrinus than in G. zaddachi and G. tigrinus matured at a smaller size and earlier than G. zaddachi. Hence, there are clear competitive advantages for the non-indigenous G. tigrinus compared to the indigenous G. zaddachi, and these may be further strengthened through ongoing environmental changes related to increased eutrophication and a warming climate in the Baltic Sea region

    Sozology for sustainable development education

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    Om贸wiono sozologi臋, dyscyplin臋 naukow膮 o systemowej ochronie 艣rodowiska naturalnego. Systemowe podej艣cie oznacza kompleksow膮 analiz臋 proces贸w i problem贸w 艣rodowiskowych z uwzgl臋dnieniem oddzia艂ywa艅 mi臋dzy elementami sk艂adowymi 艣rodowiska jako systemu, jest niezb臋dne w edukacji dla zr贸wnowa偶onego rozwoju na wszystkich poziomach kszta艂cenia.In the paper sozology as a science discipline is presented. Sozological approach includes systematic, holistic and interdisciplinary analysis of environmental processes and issues considering the interaction between elements of environment as a system. This complex approach is essential for holistic environmental education in each study level

    Ultrafiltration of waste brine from fish processing

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    W pracy przedstawiono wyniki bada艅 ultrafiltracyjnego uzdatniania solanki pochodz膮cej z przetw贸rstwa ryb. Do bada艅 zastosowano membran臋 ceramiczn膮 o zdolno艣ci rozdzielczej 150 kDa. Analizowano i oceniano zale偶no艣膰 stopnia zatrzymania bia艂ka og贸lnego, t艂uszczu i chlorku sodu oraz wydajno艣ci procesu od ci艣nienia transmembranowego i pH roztwor贸w poddawanych ultrafiltracji.Research results dealing with ultrafiltration of waste brine form fish processing are presented in the paper. The ceramic membrane with 150 kDa cut-off was used as a separation medium. Total protein, fat and sodium chloride rejection as well as permeate flux versus trans-membrane pressure and pH of feed were analyzed and discussed

    Influence of transmembrane pressure and membrane cut-off on yield and ultrafiltration selectivity of model protein concentrate solutions of whey with lactic acid addition

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    Badano proces ultrafiltracji modelowych roztwor贸w koncentratu bia艂kowego serwatki z dodatkiem kwasu mlekowego. Przeprowadzono analiz臋 wp艂ywu ci艣nienia oraz ci/f-p//'membrany na wydajno艣膰 i selektywno艣膰 procesu separacji membranowej. Wynika z niej, 偶e z punktu widzenia mo偶liwo艣ci zastosowania w bioprocesie wspomaganym membranami do otrzymywania kwasu mlekowego z odpadowej serwatki w procesie ci膮g艂ym, lepsz膮 charakterystyk臋 posiada membrana o cut-off 1 kDa w warunkach ci艣nienia transmembranowego 0,3 MPa.The ultrafiltration of model protein conccntratc solutions of whey with lactic acid addition was investigated. An influence of pressure and membrane cutoff on yield and selectivity of membrane separation process was analyzed. From a point of view of membrane-supported continuous bioprocess in the production of lactic acid from waste whey, it can be stated that the better characteristic represents the membrane of 1 kDa cut-off at transmembrane pressure of 0.3 MPa

    Investigations of modified bentonites for use in environmental protection

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    Przedstawiono wyniki bada艅 do艣wiadczalnych procesu organofilizacji bentonitu o 85% zawarto艣ci NafMMT. Badania wykonano w skali laboratoryjnej i 膰wier膰tcchniczncj z zastosowaniem MMT sodowego oraz modyfikator贸w r贸偶ni膮cych si臋 budow膮 chemiczn膮 i zawarto艣ci膮 substancji kationowo czynnej w postaci alkoholowych roztwor贸w zawieraj膮cych chlorki czwartorz臋dowych soli amoniowych. Okre艣lono wydajno艣膰 modyfikacji oraz wybrane w艂a艣ciwo艣ci otrzymanych organobentonit贸w, tj. wska藕nik p臋cznienia, cm3 i pojemno艣膰 sorpcyjn膮 CEC, mmol/100 g. Uzyskano zmodyfikowane glinki o w艂asno艣ciach hydrofobowych r贸偶ni膮ce si臋 zdolno艣ci膮 sorpcyjn膮 zale偶n膮 od rodzaju zastosowanego modyfikatora i warunk贸w prowadzenia procesu.This paper presents experimental results of the organophilization process c bentonites with 85% content of the Na + MMT. The research was pcrforme on a laboratory as well as bcnch scalc using in both cases a sodium MM' and modifiers that differ in chemical structure and contcnt of the cationicall active substance, in a form of alcoholic solutions containing quaternary am monium salts chlorides. Performance modifications and selected propertie of the organobentonites, i.e., swelling index, cm3, and the sorption capacit CEC, mmol/100 g, were specified. There were obtained modified hydro phobic clays that show various sorption capacities depending on the type c a modifier and process conditions

    Characterization of fouling in ultrafiltration ceramic membrane systems for surface water treatment

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    Research results dealing with ultrafiltration process using surface water supplying and being discharged from the fish hatchery on ceramic membranes with cut-off of 1.0 and 3.0 kDa are presented in the paper. The resistance-in- series model and modified fouling index was employed in the elaboration of results. Estimated values of fouling resistance and indexes characterize the yield of surface water ultrafiltration process. These values are essential for proper design of a larger scale membrane system.W pracy przestawiono wyniki bada艅 ultrafiltracji wody powierzchniowej zasilaj膮cej i opuszczaj膮cej wyl臋garni臋 ryb z zastosowaniem membran ceramicznych o cnt-ofj 1,0 i 3,0 kDa. Do opracowania wynik贸w zastosowano model opor贸w szeregowych oraz zmodyfikowany indeks foulingu. Oszacowane warto艣ci opor贸w hydraulicznych i indeks贸w foulingu charakteryzuj膮 wydajno艣膰 ultrafiltracji wody i s膮 podstaw膮 do prawid艂owego zaprojektowania instalacji membranowej w wi臋kszej skali

    Algorithmic procedure for water loop closure in process industries

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    W pracy przedstawiono systematyczn膮 i zintegrowan膮 metodologi臋 modyfikacji przemys艂owych sieci wodnych w celu minimalizacji zu偶ycia wody i zrzutu 艣ciek贸w. Opracowano procedur臋 algorytmiczn膮, kt贸r膮 zastosowano do analizy wybranej cz臋艣ci sieci wodnej cukrowni z pojedynczym zanieczyszczeniem. Opracowana procedura sk艂ada si臋 z algorytmu alokacji strumieni i prostego systemu eksperckiego wyboru metody oczyszczania. Uzyskano rozwi膮zania, w kt贸rych w wyniku alokacji strumieni oraz zastosowaniu mikrofiltracji jako dodatkowego procesu oczyszczania, zredukowano zu偶ycie wody, odpowiednio o 79% i 100%, w por贸wnaniu z sieci膮 przed modyfikacj膮.A systematic and integrated approach in modification of water networks in process industries is presented in the paper. An algorithmic procedure was developed and tested for a selected part of sugar plant water network with single contaminant. The developed procedure consisted of water stream allocation algorithm and a simple expert system for the selection of wastewater treatment method. The use of water streams allocation and incorporation of microfiltration as the additional treatment process enabled the fresh water intake reduction of 79% and 100% respectively, comparing to the system before modification

    Analysis of ceramic membrane fouling during ultrafiltration of protein and sodium chloride solutions

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    W publikacji przedstawiono wyniki bada艅 do艣wiadczalnych procesu ultrafiltracji modelowych i przemys艂owych solanek z zastosowaniem membran ceramicznych 150 kDa. G艂贸wnym celem bada艅 by艂a analiza wp艂ywu dw贸ch podstawowych parametr贸w operacyjnych, st臋偶enia chlorku sodu w nadawie i ci艣nienia transmembranowego TMP m fouling badanej membrany ceramicznej Al2O3/TiO2/ZrO2.Results of ultrafiltration studies using ceramic 150 kDa membrane and model solutions containing bovine serum albumin and sodium chloride as well as salted wastewater from fish industry are reported. A main objective of this work was to study the effect of two main operating parameters, i.e. sodium chloride concentration in feed solution and transmembrane pressure, TMP, on fouling behavior of ceramic Al2O3/TiO2/ZrO2. membrane during ultrafiltration tests

    Application of ultrafiltration in culture water recycling in fish hatchery

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    Wody zasilaj膮ce i opuszczaj膮ce wyl臋garnie ryb musz膮 by膰 poddawane efektywnemu oczyszczaniu ze wzgl臋du na konieczno艣膰 optymalizacji procesu inkubacji ikry i ochrony 艣rodowiska wodnego. Celem bada艅 jest przetestowanie procesu ultrafiltracji i membran ceramicznych l kDa, jako metody usuwania zawiesiny, fosforu i 偶elaza oraz redukcji poziomu BZT-, i ChZT z w贸d kr膮偶膮cych w obiegu zamkni臋tym malej wyl臋garni. Uzyskane wyniki wskazuj膮, 偶e badana technika membranowa mo偶e by膰 wykorzystana w gospodarce wodno-艣ciekowej wyl臋garni do recyklingu wody.Feed and wastewator from aquaculture facilities must be effectively treated for environmental and embryological reasons. The objective of this study was to evaluate ultrafiltration process using a ceramic 1 kDa membrane asa treatment option for removal of total suspended solids, total phosphorous and iron, and reducing BOD and COD level in closed loop of cyclic water in fish hatchery. The obtained results indicate that the tested membrane and technique employed can be used in full-scale treatment technology for culture water recycling

    Membrane fouling in the ultrafiltration of water鈥損rotein鈥搒odium chloride model systems

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    This paper presents ultrafiltration results of model BSA (bovine serum albumin) and MB (myoglobin) solutions prepared with or without NaCl addition. The protein concentrations in the solutions were equal to 0.05 g dm 3 for MB and 0.5 g dm 3 for BSA. The ultrafiltration tests were performed using a laboratory scale unit equipped with 90 mm ceramic disc membranes with a filtration area of 5:6-10-3 m2 and cut-off of 50 or 150 kDa. The tests were run under constant process conditions, i.e. a cross flow volume (CFV) of 5 ms-1, transmembrane pressure (TMP) of 0.2 MPa, temperature of 20 鈼 and NaCl concentration of 0 or 10 wt%. The installation worked in a semi-open mode with a continuous permeate discharge and retentate recycle. The performance of the membranes was measured with the permeate volumetric flow rate, JV (m3m 2s 1) while their selectivity was determined by the protein rejection, R. The paper evaluates and discusses the protein rejection mechanisms as well as the influence of the membrane cut-off and sodium chloride concentration in the feed on the flux decline during the ultrafiltration of BSA and MB. Moreover, it provides an analysis of the first fouling phase by applying usual filtration laws
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