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Enzymatic Activity of Some Industrially-Applied Cellulolytic Enzyme Preparations

Abstract

Enzymatic hydrolysis is the essential step in the production of 2nd generation biofuels made from lignocellulosic biomass, i.e. agricultural or forestry solid wastes. The enzyme-catalysed robust degradation of cellulose and hemicellulose to monosaccharides requires the synergistic action of the independent types of highly-specific enzymes, usually offered as ready-to-use preparations. The basic aim of the study was to experimentally determine the enzymatic activity of two widely industrially-applied, commercially available cellulolytic enzyme preparations: (i) Cellic® CTec2 and (ii) the mixture of Celluclast® 1.5L and Novozyme 188, in the hydrolysis of pre-treated lignocellulosic biomass, i.e. (a) energetic willow and (b) rye straw, or untreated (c) cellulose paper as well, used as feedstocks. Before the hydrolysis, every kind of utilized lignocellulosic biomass was subjected to alkaline-based (10% NaOH) pre-treatment at high-temperature (121°C) and overpressure (0.1 MPa) conditions. The influence of the type of applied enzymes, as well as their concentration, on the effectiveness of hydrolysis was quantitatively evaluated, and finally the enzyme activities were determined for each of tested cellulolytic enzyme preparations.

Open access
Fate and Removal of Pharmaceuticals and Illegal Drugs Present in Drinking Water and Wastewater

Abstract

Rapid development of pharmaceutical industry, and thus widespread availability of different types of therapeutical and increased intake of pharmaceuticals, results in elevated concentrations of pharmaceuticals in municipal wastewater subjected to treatment in wastewater treatment plants. Pharmaceuticals present in raw wastewater discharged from hospitals, households, veterinary and health care clinics eventually end up in wastewater treatment plants. Commonly applied methods for treating wastewater do not allow complete removal of these contaminants. As a consequence, pharmaceuticals still present in treated wastewater are introduced to water environment. The most frequently identified pharmaceuticals in surface water belong to the following groups: non steroidal anti inflammatory drugs, beta-blockers, estrogens and lipid regulators. The most difficult is removal of diclofenac, clofibric acid and carbamazepine as these substances show low biodegradability. Diclofenac can be removed in the process of wastewater treatment by 40%, carbamazepine by 10%, and clofibric acid from 26 to 50%. The presence of diclofenac sodium in the rivers in Poland was confirmed and the concentrations were following: 380 ng/dm3 (the Warta river), 470 ng/dm3 (the Odra river), 140 ng/dm3 (the Vistula river). Naproxene was found in the Warta river at the concentration of 100 ng/dm3. The presence of pharmaceuticals in surface water can be toxic to aqueous microorganisms and fish. Recent studies confirmed also the presence of pharmaceuticals in drinking water. This is considered as a problem especially in urban agglomerations such as Berlin or large cities in Spain and China. The studies showed that pharmaceuticals were also identified in the samples taken from the Polish rivers and drinking water. The presence of naproxene and diclofenac at the concentrations of 13 and 4 ng/dm3 was identified in drinking water sampled from water intakes in Poznan. Surface water and drinking water showed also the presence of illegal drugs.

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Influence of Selected Coagulants of Indicator and Dioxin-Like PCB Removal from Drinking Water

Abstract

The aim of the research was to compare selected coagulants efficiency in indicator and chosen dioxin-like PCB removal from surface water. As coagulants, there were used aluminium sulfate and 5 hydrolyzed polyaluminium chlorides, with trade names: PAX-XL1, PAX-XL10, PAX-XL19, PAX-XL60, PAX-XL69. For the research, surface water was used, collected from dam reservoir. The water composition was modified with standard mixtures PCB MIX24 and MIX13, in order to obtain concentration of each congener equal to 300 ng/dm3. The PCB MIX24 mixture was composed of indicator congeners solution: 28, 52, 101, 118, 138, 153, and 180, whereas the MIX13 mixture - solution of three dioxin-like PCB 77, PCB 126, and PCB 169. It was demonstrated that the application of aluminium sulfate allowed for reaching better effects for purifying water of PCB, than with the usage of pre-hydrolyzed salts, polyaluminium chlorides. Out of the studied coagulants, the best effects for indicator PCB removal were obtained with the application of aluminium sulfate, total PCB concentration was decreased by 65%. The highest efficiency for indicator congeners removal (90%) was obtained for PCB 138 and 153. After the application of hydrolyzed polyaluminium chlorides PAX-XL1, PAX-XL10 decrease in higher chlorinated PCB concentration was obtained, in the range of 23 to 74%. Selectivity of chosen PCB congener removal, depending on applied coagulant, was demonstrated; with the usage of aluminium sulfate, removal of heptachlorobiphenyl PCB 180 at the level of 34% was obtained, whereas with the application of PAX-XL1 and PAX-XL10 higher reduction efficiency for this congener was obtained, i.e. 83 and 74% respectively. For dioxin-like PCB, after application of aluminium sulfate, total concentration reduction by 74% was obtained, efficiency of this congeners removal amounted to from 54 (PCB 77) up to 72% (PCB 126), similar results were obtained after the usage of PAX-XL1. The lowest PCB removal from water rate was stated for coagulants PAX-XL60 and PAX-XL69.

Open access
Kinetic and Isotherm Analysis of Cu(II) Adsorption onto Almond Shell (Prunus Dulcis)

Abstract

In the work, adsorption of Cu2+ ions onto almond shell were investigated under different operational conditions. Almond shell was used without any pretreatment prior to the tests. The optimum conditions for adsorption of Cu2+ ions through almond shell were determined to be; pH 5.0, temperature 20°C, shaking rate 125 rpm, sorbent dose 0.3 g and initial Cu2+ ion concentration 50 mg/dm3. The equilibrium duration of the system was 60 minutes. The sorption capacities of the sorbents were predicted with the aid of equilibrium and kinetic models. The interactions of peanut shell with metal ions were constituted by SEM, EDX, FT-IR, XRD and AFM. The pseudo-first-order, pseudo-second-order, Weber-Morris, Elovich model and Bangham kinetic models were applied to test the experimental data. The Cu+2 ions adsorption onto almond shell was better defined by the pseudo-second-order kinetic model, for initial pH. The equilibrium data were evaluated using Langmuir, Freundlich, Temkin, D-R and Harkins Jura isotherms. The highest R2 value in isotherm studies was obtained from Langmiur isotherm (R2 = 0.98) for the inlet concentration.

Open access
Potential Use of Alluvial Groundwater for Irrigation in Arid Zones - Mhamid Oasis (S Morocco)

Abstract

In arid zones, the availability of fresh water is usually very limited because of high salinity, which greatly limits their use for irrigation purposes. High mineralization of water used for irrigation leads to increased soil salinity. The aim of the study was to examine the potential use of alluvial groundwater for irrigation in arid zones. The works were conducted in the Middle Draa Valley in southern Morocco (the Mhamid Oasis) in October 2015. Water samples of alluvial groundwater were collected for laboratory analysis from 42 wells located in the oasis. In order to determine the possibility to use the water for irrigation purposes, the Sodium Adsorption Ratio (SAR), sodium percentage (%Na), permeability index (PI), Kelly’s ratio (KR), magnesium hazards (MH) and electrical conductivity (EC) were assessed. EC values, exceeding 3000 μS·cm-1 in all the samples, classify the water as unsuitable for irrigation. MH and the KR indexes show that 30% of water samples represent levels making them unsuitable for irrigation. SAR confirms the very high degree of susceptibility of the analyzed waters to salinity hazard. The PI index of these waters is moderate, however in terms of sodium content they can be deemed suitable for irrigation purposes. It has been found that even within a small area of the oasis, a very large differentiation in the alluvial groundwater suitability for irrigation purposes occurs.

Open access
Surfactants in Klodnica River (Katowice, Poland). Part I. Linear Alkylbenzene Sulphonates (LAS)

Abstract

Surfactants are a group of compounds with specific physico-chemical properties and therefore they are used in many spheres of human activity. Surface-active substances undergo various physico-chemical transformations, what enables their migration between different elements of the environment and may lead to its pollution. Selected anionic surfactants were determined in samples of water from the Klodnica river (25 samples) and bottom sediments (25 samples). In most samples the presence of anionic analytes was confirmed. The determined concentration levels were in the range of up to 0.2105±0.0023 mg/dm3 or 0.207±0.010 μg/kg (surface water and bottom sediment samples, respectively). Comparing the concentrations of certain analytes found in liquid and solid environmental samples, it can be noticed that the surfactants containing a shorter alkyl chain in a molecule were present in higher concentrations in liquid samples (hydrophobicity increasing with the increasing length of the chain) and the other way round.

Open access
The Use of Moss Pleurozium schreberi (Brid.) Mitt. as Bioindicator of Radionuclide Contamination in Industrial Areas of Upper Silesia

Abstract

Mosses are good bioaccumulators of radionuclides and from the 60 of the last century, they are used as bioindicators of radioactive contamination in the environment. Concentration of impurities in moss represent the accumulation in mosses during the past 2-3 years. As a result, the moss composition analysis provides information on an average contamination within a few vegetation seasons. During our survey the measurements of radionuclide activity concentrations in P. schreberi transplanted from places relatively clean to heavily contaminated areas of Upper Silesia were carried out. An increase in the radionuclides activity concentrations in P. schreberi transplants may indicate not only deposition of the radionuclides itself, but also an influx of other pollutants. The results showed no relationship between the Pb-210 activity concentration and activity concentrations of Pb-214, Bi-214, also belonging to the uranium-radium decay series. The increased concentration of Pb-210 in P. schreberi may be the result of the radionuclide atmospheric deposition, which appears in the environment as a result of fossil fuels burning. Excess, allogeneic Pb-210 can be used as marker of environmental pollution. In the areas with its higher activity concentration increased pollution can be expected delivered, for example, by local industry. The Project received financial assistance from the funds of the National Science Centre, granted by force of the decision no. UMO-2013/09/B/NZ8/03340 (NCN).

Open access
Vertical Migrations in an Alpine Grassland Cambisol after Long-Term Sewage Sludge Application

Abstract

Differences between vertical mobilities of nutrient and trace elements within a long-term sludge-treated and an adjacent untreated Alpine grassland cambisol were investigated by column experiments. The site had been intensely fertilized with urban sewage sludge for 10 years of 7.5 Mg/ha annually, whereas an adjacent site had been left untreated. A model column experiment was set up to investigate changes of permeabilities and trace element retentions at 0-20 cm and 20-60 cm layers thereof. Elution was performed with de-ionized water at amounts of expected rainfall at the sampling site (1000 mm), as well as with equal volume of manure after biogas production. Long-term sludge treatment increased organic carbon, formation of ammonium and nitrate, and increased vertical mobility of K, P, S, Cu, and Fe, but also slightly higher (below 10-fold) for Na, Sr, Ba, Ni and V. Additional application of manure was of minor effect, mainly upon nitrate formation, and upon leaching of Fe, Mn as well as Fe/Mn proportion. Prior addition of FeCl2 to the manure in order to increase sulfide precipitation, mainly affected the output of ammonia, but hardly the cations or anions (e.g. P) investigated.

Open access
Ammonia Emission from Sewage Sludge Incineration Process

Abstract

In quantitative terms, sludge produced in the process of municipal wastewater treatment represents a small part of the total waste generated in municipal sources - its quantity represents only a few percent of the generated mass of municipal waste. However, the threats it brings, do not allow it to be neglected while designing the wastewater treatment process. At the same time, with increasing requirements regarding the quality of sewage discharged into the environment, there is an increase in the amount of sludge produced in wastewater treatment processes. In recent years, the share of thermal treatment of municipal sewage sludge has risen sharply - about 12 modern sludge incineration plants have been built and construction of new ones is considered. During more than a four-year operation of the sewage sludge incineration plant in the Combined Sewage Treatment Plant in Lodz (GOS) a large ammonia emission from the combustion process was observed. So, a decision was taken to examine this process. The paper presents results of ammonia emission from the combustion of sewage sludge from GOS as a function of temperature.

Open access
Application of Chemometric Analysis to the Study of Snow at the Sudety Mountains, Poland

Abstract

Snow samples were collected during winter 2011/2012 in three posts in the Western Sudety Mountains (Poland) in 3 consecutive phases of snow cover development, i.e. stabilisation (Feb 1st), growth (Mar 15th) and its ablation (Mar 27th). To maintain a fixed number of samples, each snow profile has been divided into six layers, but hydrochemical indications were made for each 10 cm section of core. The complete data set was subjected in the first run of chemometric data interpretation to Cluster Analysis as well as Principal Components Analysis. Further, Self-Organizing Maps, type of neutral network described by Kohonen were used for visualization and interpretation of large high-dimensional data sets. For each site the hierarchical Ward’s method of linkage, squared Euclidean distance as similarity measure, standardized raw data, cluster significance test according to Sneath’s criterion clustering of the chemical variables was done. Afterwards this grouping of the chemical variables was confirmed by the results from Principal Components Analysis. The major conclusion is that the whole system of three sampling sites four patterns of variable groupings are observed: the first one is related to the mineral salt impact; the second one - with the impact of secondary emissions and organic pollutants; next one - with dissolved matter effect and the last one - with oxidative influence, again with relation to anthropogenic activities like smog, coal burning, traffic etc. It might be also concluded that specificity of the samples is determined by the factors responsible for the data set structure and not by particular individual or time factors.

Open access