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Polish Journal of Chemical Technology (v.9, #4)

Evaluation of colloidal silica obtained via the co-precipitation method using octane as an organic phase by Teofil Jesionowski; Beata Tepper; Andrzej Krysztafkiewicz; (pp. 1-4).
The studies were conducted on the production of silica from emulsion systems by co-precipitation from solutions of sodium metasilicate and hydrochloric acid and octane were used as an organic medium. The obtained products were subjected to a comprehensive physicochemical analysis in order to define their dispersive and morphological properties. Particle diameters and polydispersity were determined by the NIBS (non-invasive back scattering) method while the shape and morphology of the particles were established using scanning electron microscopy (SEM). In order to determine the adsorptive properties of the obtained monodisperse silicas, isotherms of nitrogen adsorption/desorption on their surfaces were determined. Using the isotherms, also the specific surface area, the diameter and the volume of the pores were established. In order to define the hydrophilic/hydrophobic character of the products, profiles of wettability and of sedimentation in water were examined. The obtained products were well wettable with water and an increase in their weight depended on the amount of the applied surfactants. The particles of the precipitated silicas manifested a defined, spherical shape and showed a relatively low polydispersity.

Keywords: precipitated silica; emulsion; PSD; SEM; sedimentation; wettability

Studies on the recrystalization of nanocrystalline metals by Zofia Lendzion-Bieluń; Marta Gleń; (pp. 5-7).
The influence of the promoters such as CaO, Al2O3 and K2O on the specific surface area of the nanocrystalline cobalt was determined. The recrystalization process of the nanocrystalline cobalt was determined and compared with the examinations conducted on the iron catalyst for ammonia synthesis. The triply promoted nanocrystalline obtained cobalt after the annealing process, has got greater specific surface area than the triply promoted iron.

Keywords: nanocrystalline cobalt; recrystalization

Environmental management concepts supported by information technology by Julia Natalia Hoffmann; Edward Radosiński; (pp. 8-13).
The genesis and development of environmental management concepts are presented. An overview of the current environmental management ideas, programmes and systems, including Sustainable Development, Responsible Care, Cleaner Production, environmental management based on ISO 14000, and EMAS is provided. Selected computer-aided tools and techniques for improving the quality of environmental management are proposed.

Keywords: environmental management; sustainable development; improvement methods and tools

The effect of sewage sludge composts and potato pulp on uptaking of macroelements by the grain and straw of the spring triticale by Józefa Krzywy; Edward Krzywy; Ewa Krzywy-Gawrońska; Monika Rozmarynowska; (pp. 14-17).

Taking into consideration the acid pH soil, high content of potassium in relation to nitrogen and phosphorus and the insignificant quantity of heavy metals in the potato pulp and the slight alkaline pH soil as well, high amount of nitrogen and phosphorus in relation to potassium in the municipal sewage sludge, the experiment was carried out in order to define the effect of composts from these waste on uptaking macroelements by the grain and the straw of the Wanad variety spring triticale.

The vegetative - pot experiment was carried out on the brown incomplete soil of the slight acid pH (pHKCl 6,1), of the granulometric composition of slight loam (V complex), an average content of available forms of phosphorus and potassium and a high content of magnesium.

The obtained results show that the grain and the straw of spring trticale took distinctly more macroelements under the influence the fertilization of the composts with the municipal sewage sludge (30%) and the potato pulp (30%) in comparison with the composts with the 60% participation of the potato pulp. The supplementary mineral fertilization which was used against in comparison to composts, increased uptaking the macroelements by the tested plant. The double dose of composts and mineral fertilizers visibly increased nitrogen, phosphorus, potassium, cooper, magnesium and sulphur absorbance by the grain and the straw of spring trticale in comparison with the series with a single dose of composts and a supplementary mineral fertilization.

Keywords: municipal sewage sludge; potato pulp; composts; uptaking macroelements by spring triticale

Band reactor for toxic and recalcitrant water contaminants by Bożena Czech; Wieslawa Ćwikła-Bundyra; (pp. 18-20).
This paper deals with the problem of the photocatalytic reactor construction. The supported TiO2 on γ- Al2O3 modified with Mo or V addition was used as the photocatalyst, whereas phenol and formaldehyde were chosen as the model pollutants. The counter - current contact of reagents and catalysts is the main advantage of the construction and enables a significant COD reduction of the highly concentrated wastewaters.

Keywords: photocatalysis; photoreactors; Me-TiO2/Al2O3wastewater treatment; phenol; formaldehyde

The influence of thermal processing of sewage sludge on the usage properties of the formed ash by Katarzyna Gorazda; Zbigniew Wzorek; Marek Jodko; (pp. 21-27).
The influence of sewage sludge incineration temperature on the formed ash constitution was examined. The comparative extraction tests of two differently prepared ashes (laboratory and industrial) were carried out in order to verify if the parameters of sewage sludge incineration influence the extraction selectivity of phosphorus compounds. The laboratory ash (Alab) were prepared from sewage sludge incinerated at 950°C on a laboratory scale while the industrial ash (Aind) comes from thermal utilization system of the sewage sludge at the Gdynia Sewage Treatment Plant, which uses fluid-bed furnace incineration at 850 - 900°C. It was found that the temperature and the conditions of the sewage sludge incineration process have an effect on the usage properties of the formed ash. Despite the twofold lower Fe content in the industrial ash than that of the laboratory one, its content in extracts after phosphoric acid leaching is 4.7 times higher. The lower values of PO43- leaching degree from the industrial ash than the laboratory ash were observed, as well as a decrease of extraction productivity.

Keywords: phosphorus recovery; ash properties; ash extraction; industrial ash

The morphological and dispersive characterization of commercial titanium dioxides by Teofil Jesionowski; Katarzyna Siwińska-Stefańska; Andrzej Krysztafkiewicz; Jadwiga Sójka-Ledakowicz; Joanna Koprowska; Joanna Lewartowska; (pp. 28-35).
The physicochemical and dispersive characterizations were conducted on the selected commercial titanium dioxides produced by, Z. Ch. POLICE, S. A. The dispersive properties were defined in detail by an analysis of particle size distribution and polydispersity index. Moreover, the microscope studies were executed to evaluate the surface morphology of the studied TiO2 forms. The profiles of titanium dioxides sedimentation in water were determined and the specific surface areas were defined by the BET method.

Keywords: TiO2surface morphology; particle size; polydispersity; sedimentation; specific surface area

Granulated organic and mineral fertilizers: Technology and utility properties by Czesława Rosik-Dulewska; Jolanta Robak; Katarzyna Głowala; (pp. 36-39).
This work presents the selected aspects of a technological concept for the production of organic and mineral fertilizers from communal sludge stabilized with volatile ash, by using two methods of granulation: coating and pressure. The presented concept is the effect of optimization, taking into account an interference of a number of factors exerted onto the fertilizing values and the mechanical strength of the final products. The fertilizers (contain ash from brown coal) obtained according to that method are characterized by a sufficient (according to law) content of organic matter (35,73% w/w), total nitrogen (1,70% w/w), phosphorus P2 O5 (3,62% w/w) and after the modification, also potassium K2O (8,43% w/w). The mechanical properties are better for the granulates, prepared by using pressure granulation (15,1 kG/cm2) and allow for their transportation, storage and application.

Keywords: organic and mineral fertilizers; sludge; volatile ashes; granulation

The oily wastewater treatment using the nanofiltration process by Aleksander Orecki; Maria Tomaszewska; (pp. 40-42).
The objective of this work was to investigate the possibility of oily wastewater treatment using the nanofiltration (NF) process. The NF studies were carried out with a permeate obtained from ultrafiltration (UF) (used for the treatment of the oily wastewater from metal industry). The influence of transmembrane pressure on a permeate flux, the degree of the rejection of oil and inorganic compounds was investigated. The studies on the NF treatment of oily wastewater demonstrated a high effectiveness of the rejection of oil and inorganic compounds. The permeate obtained from the treatment was free of oil. Moreover, the retention coefficient of the inorganic compounds was higher than 75% for all the cations examined (Na+, K+, Mg2+, Ca2+, Zn2+, Cu2+) and higher than 95% for sulphates. Therefore, the permeate obtained in the NF process can be reused for fresh emulsion preparation.

Keywords: nanofiltration; oily wastewater; inorganic compounds

Application of combustible wastes for the alternative fuels production by Marek Kułażyński; Andrzej Surma; Jerzy Walendziewski; (pp. 43-47).
The information on the quantity of various types of combustible wastes registered in the Lower Silesia Marshal Office over the 2003 - 2005 years (waste codes - 02, 03, 04, 07, 12, 15, 16, 17, 19 and 20) was collected and then the quantities of individual wastes from different sources were summarized depending on the waste sort i.e. waste paper (cellulose), plastics, timber, textiles and rubber. The physiochemical properties and the chemical composition of the impurities in the selected waste sorts were determined and discussed while taking into account their usefulness and the necessary treatment operations for the alternative fuels production.

Keywords: industrial wastes; municipal wastes; alternative fuels; calorific value; waste codes; combustible materials; combustion

The effect of bottom sediment on biomass production by Italian ryegrass and maize by Barbara Wiśniowska-Kielian; (pp. 48-51).
A two-year pot experiment (2005 and 2006) was conducted to estimate an effect of dredged bottom sediment from Rożnów Reservoir addition to the light, very acid soil on the plant biomass production. The sediment was applied in the amount from 1 to 20% of the substratum mass. Italian ryegrass (Lolium multiflorum L.) and maize (Zea mays L.) were cultivated as the successive test plants. The lowest amount of plant biomass was obtained on the soil (control) and each sediment addition to the substratum caused an increase of the biomass production, both tops as well as the roots of the plant. Larger sediment additions (7% and more) caused a significant increase of the yield, of both the individual plant species and the total biomass during the two years of the experiment. The bottom sediment added to the light, very acid soil distinctly improved the plant yielding and the way of biomass utilisation should be assessed on the basis of its chemical composition analysis.

Keywords: bottom sediment; utilization; Italian ryegrass; maize; biomass production; estimate

The influence of fluorine on municipal sewage biological treatment by Joanna Gluzińska; Marian Legutko; (pp. 52-55).
The authors examined the influence of fluorine as a factor disrupting the processes of municipal sewage biological treatment. Sodium fluoride was introduced to a municipal plant sewage treated in an oxygen zone, acting as a simulator of uncontrolled industrial sewage discharge. The influence of fluoride ion concentration and the duration of sewage treatment on its biological purification processes were examined. Also, the dependencies of the direction of changes in inorganic nitrogen connections, phosphorus concentration, COD and fluorine on the initial fluorine compound content in the purified sewage were determined. Research samples of the municipal sewage were drawn at the opening of the oxygen zone in a typical municipal sewage treatment plant (RLM > 100 000) employing intensified biogenic substance removal.

Keywords: oxygen processes; activated sludge; environment protection

Catalityc removal of nitrogen oxide from combustion gases by Wiesława Ćwikła-Bundyra; (pp. 56-58).
Nitrogen oxide conversion to nitrogen over Pt/Al2 O3, Pd/Al2O3, Rh/Al2O3 catalysts was investigated. The results of the catalytic activity investigations, with the iso-x method, showed that NO reduction by methane occurs at a reasonable rate at the temperature range 200-500°C. Alumina-supported Pd, Pt and Rh catalysts have been compared for the selective reduction of NO to N2. All the catalysts showed good activity in NO reduction by methane, giving around 80 - 90% N2 production. At moderate temperatures Pt is the most active catalyst for the removal of NO.

Keywords: catalytic reduction of NO by methane; Platinum group metals catalysts

Utilization of the post-filtration lye from the SCS method of soda production by Mieczysław TrypuĆ; Sebastian Drużyński; Urszula Kiełkowska; Krzysztof Mazurek; (pp. 59-62).
The mutual solubility of salts in the NaVO3-NaNO3-H2O system was investigated at 293 - 323 K temperature range by the method of isothermal saturation of solutions. A fragment of the solubility polytherm for that system was plotted, based on the obtained data. The investigated system is a part of the quaternary NH4NO3-NaVO3-NH4VO3-NaNO3 system, and it is necessary for plotting the solubility isotherm as a planar projection according to Janecke, since it defines one edge of its square. Knowledge of the isotherm for that quaternary system is necessary to determine the optimal utilization conditions for the post-filtration lye, formed during the soda production from NaNO3 by the Solvay method, using NaVO3.

Keywords: mutual solubility; sodium metavanadate; sodium nitrate; ternary system

Uncommon applications of statistical methods of the design of experiments in chemical technology and environment protection by Grzegorz Lewandowski; Jan Ćwirko; (pp. 63-67).

The review of literature related to the applications of statistic methods of design of experiments in chemical technology and environment protection was presented in the work. The research that consists of two stages: a stage of choosing the best variables describing an experimental object and a stage of proper experimental investigation, seems particularly interesting.

An interesting example of an application of statistical strategies in environmental protection is the optimization of photoactivity of TiO2/SiO2 mixture, received by a sol-gel technique. TiO2, due to its specific feature, was applied in the photocatalytic methods of removing toxic compounds from water and air. In the experiments there were used two designs - the fractional factorial design 25-1 (as the elimination one) and the central composite design (as the proper one). Following the data analysis from the elimination plan two variables were eliminated, which helped to simplify the research object.

Among other uncommon applications of the design of experiments: the optimization of the conditions for the extraction of natural pigments used in dyeing food, the production of fatty acid methyl esters used as diesel oil substitutes (biodiesel) and the optimization of a supercritical fluid extraction methodology for the analysis of castor oil, should be mentioned.

Keywords: design of experiments; optimization; central composite designs; dyes; esterification; TiO2 photoactivity; biodiesel

Application of the design of experiments in the epoxidation process of 1,5,9-cyclododecatriene by Grzegorz Lewandowski; Jan Ćwirko; (pp. 68-71).
An influence of the molar ratio of cis, trans, trans-1,5,9-cyclododecatriene to tert-butyl hydroperoxide, the concentration of the catalyst and the reaction time on the performance of the epoxidation process of cis, trans, trans-1,5,9-cyclodecatriene with tert-butyl hydroperoxide at the presence of molybdenum hexacarbonyl Mo(CO)6 was examined. Examinations were performed using statistical methods of the design of experiments. A mathematical model describing the influence of the parameters on conversion cis, trans, trans-1,5,9-cyclododecatriene was obtained. An analysis of the data and rests was performed and an optimal value of conversion of cis, trans, trans-1,5,9-cyclododecatriene was established.

Keywords: epoxidation; design of experiments; 1,5,9-cyclododecatriene; optimization

Characterization of TiO2 surface following the modification with silane coupling agents by Teofil Jesionowski; Katarzyna Siwińska-Stefańska; Andrzej Krysztafkiewicz; Jadwiga Sójka-Ledakowicz; Joanna Koprowska; Beata Pęczkowska; (pp. 72-76).
Studies were conducted on the modification of titanium white surface using selected silane coupling agents. The effect of the concentration of the organic coupling agents was examined (0.5; 1 or 3 weight parts per 100 weight parts of TYTANPOL R-003, TYTANPOL R-211 or TYTANPOL R-213 preparation of titanium white). The dispersive properties were determined by an estimation of the particle size distribution curves and of the polydispersity index. Moreover, microscopic observations were conducted permitting to evaluate the surface morphology of the modified TiO2 particles. The profiles of sedimentation in water were also determined for the titanium whites and the BET specific surface areas were determined. Selected samples of the modified and unmodified titanium whites were subjected to elemental analysis.

Keywords: titanium dioxide; surface modification; silane coupling agents; PSD; surface morphology; adsorption/desorption isotherms; dispersion

Surface characterization of different particles arising as a result of coal combustion process in selected power plants from Central Poland using ToF-SIMS by Jacek Grams; Katarzyna Bawolak; (pp. 77-80).
The aim of this work was the ToF-SIMS investigations of different particles arising as a result of a coal combustion process in selected power plants from Central Poland. The chemical composition and distribution of particular compounds on the studied surfaces were determined. Moreover, the ratio of the quantity of aromatic and aliphatic hydrocarbons adsorbed on the surface of the particles was estimated. A qualitative analysis of the studied samples demonstrated the presence of a big number of various compounds, including heavy metals such as Pb, Cd and As on the investigated surfaces. In the prevailing number sample components were distributed non-homogenously on the surface and the larger areas richer in a certain type of ions were observed.

Keywords: ToF-SIMS; particle; coal combustion; power plant

Controlled release fertilizers by Krzysztof Lubkowski; Barbara Grzmil; (pp. 83-84).
The efficiency of nitrogen assimilation by plants is rather low and this is a serious problem in view of environmental protection. Improvement of nitrogen absorption can be carried out through the developing, producing and applying the controlled release fertilizers. Biodegradable chitosan has been proposed as an alternative material in the production of controlled release fertilizers.

Keywords: controlled release fertilizers; chitosan

Application of the TOF-SIMS and SEM-EDS methods to assess the influence of dusting from a phosphate waste deposal place based on hair analysis by Małgorzata Iwona Szynkowska; Ewa Leśniewska; Aleksandra Pawlaczyk; Jacek Rogowski; Tadeusz Paryjczak; (pp. 85-90).
In this work, scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS) and the time-of-flight secondary ion mass spectrometry (TOF-SIMS) were used to study the particles present on the hair surface of the inhabitants of Wislinka (people environmentally exposed due to the closeness of a dump) in order to obtain the information about the possible influence of dusting from a phosphate waste deposal place. Additionally, the morphology and the composition of fresh phosphogypsum were analyzed. Waste phosphogypsum is formed in the process of a wet phosphoric acid production and there is still a problem with its storage. A thorough understanding of the composition and chemistry of phosphogypsum seems to be necessary to evaluate its environmental impact comprehensively. The results obtained from these two techniques turned out to be complementary and revealed the information expected.

Keywords: phosphogypsum; surface analysis; hair; SEM-EDS; TOF-SIMS

A model of the meat waste management by Zygmunt Kowalski; Kinga Krupa-Żuczek; (pp. 91-97).
The European Union produces about 18 million tons of waste from meat industry per year. The real danger of the BSE disease caused a necessity of looking for a new alternative solution of meat waste management. The proposed solution of meat industry waste management would create meat production waste free with the use of the cleaner production method. Cleaner production includes: pollution prevention, reduction of the source, recovery of materials and energy (for example: the recovery of blood plasma and protein hydrolisate from bone sludge) and their recycling. The thermal processing of meat industrial waste (bone sludge, meat-bone meal and odour) is anticipated, too. Ashes from meat calcining have the phosphorus content close to its concentration, of the typical phosphoric raw materials. That confirmed the possibility of using such ashes as the substitute of phosphoric raw materials. The target model of waste free meat waste management included the results of the implemented and current research.

Keywords: meat waste; cleaner production; waste management; model solution

The influence of the composts with the participation of municipal sewage sludge on the available forms of phosphorus in the soil as well as the yield of the seeds of spring rape by Edward Krzywy; Ewa Krzywy-Gawrońska; Józefa Krzywy; Izabela Gutowska; (pp. 98-101).
The field and laboratory experiment was carried on the brown incomplete soil of the complex of rye good. The obtained results in the yield experiment show that the composts with the participation of municipal sewage sludge increased essentially the yield of the seeds of spring rape in comparison with the control variant. Doubling of the doses of mineral nitric - potassium fertilization against the background of the composts did not have a significant influence on increasing the yield of the seeds of spring rape in comparison with the single doses. The composts with the participation of municipal sewage sludge in the field and laboratory experiment caused a significant increase of the content of the available forms of phosphorus in the soil. As time went by the distribution of the composts in the soil, the content of the available forms of phosphorus increased.

Keywords: compost; municipal sewage sludge; seeds yield; soil

The effect of composts from potato pulp and municipal sewage sludge for changes of microelements in the soil during incubation by Ewa Krzywy-Gawrońska; Monika Rozmarynowska; (pp. 102-106).
The total and soluble content of microelements in the soil was described in the laboratory experiment. The soil was incubated with three doses of composts with a participation of municipal sewage sludge and potato pulp. The obtained results of the experiment pointed that all the composts increased an average total content and the forms soluble in 1 M HCl of microelements in the soil in comparison with the control. In the majority of the variants, the composts made with the 70% participation of municipal sewage sludge and 30% addition of straw or sawdust caused an increase of the content of the analyzed elements in the soil than the composts with the 70% participation of potato pulp and 30% addition of straw or sawdust. The differences are connected with a higher content of microelements, which were put in the soil, with the composts with the 70% participation of municipal sewage sludge and 30% addition of straw or sawdust. There are no differences in the formation of the content of microelements in the soil, which were depended on the type of the structural - formative component during the production of composts. The quantity of the composts' dose had an influence on the formation of the participation of the soluble form of microelements in the total content in the soil. The participation of the soluble form of cadmium, cooper, manganese and nickel in the total content in the soil increased along with increasing the dose of composts. The content of the total forms in the soil incubated with the composts included in the standard for the light soils.

Keywords: potato pulp; municipal sewage sludge; composts; soil; microelementsl

The influence of ozonation on the activated carbon adsorption of phenol and humic acid by Bożena Seredyńska-Sobecka; Maria Tomaszewska; (pp. 107-110).
To study the influence of ozonation on the activated carbon adsorption, a model solution containing approximately 8 mg/dm3 of humic acid and approximately 1 mg/dm3 of phenol has been ozonated, and then adsorption kintetics and adsorption isotherm experiments have been performed. The applied ozone doses ranged from 1 to 3 mg O3/dm3, and a contact time was 1 min. In the adsorption experiments, the commercial activated carbon CWZ-30 (Gryfskand Sp. z o.o., Hajnówka, Poland) has been used. Phenol adsorption under equilibrium conditions was determined by the Freundlich isotherm equation, and the modified Freudlich isotherm equation has been employed for the determination of humic acid equilibrium adsorption. The applied oxidation conditions resulted in color, chemical oxygen demand (COD), total organic carbon (TOC) and UV254 absorbance removal, by 4 - 13%, 3 - 6%, 3 - 7%, respectively. After ozonation, phenol concentration decreased by 6 - 23%. These changes in the model solution did not affect the humic acid adsorption, however, they deteriorated phenol adsorption.

Keywords: ozonation; powdered activated carbon; adsorption isotherms; phenol; humic acid

Preparation methods of calcium sulphate and urea adduct by Przemysław Malinowski; Andrzej Biskupski; Józef Głowiński; (pp. 111-114).
The paper presents the results of laboratory studies on the preparation of calcium sulphate and urea adduct by: grinding, compacting and mixing in the presence of physical water. A method for the measurement of urea conversion into the adduct form, which is based on the difference in solubility of free urea and the adduct bound urea CaSO4·4CO(NH2)2 in n-butanol, was developed. Mixing the reagents in the presence of physical water produced the best results. High urea conversion into the adduct form, over 85%, in the prepared samples indicates that this method can be successfully used to get CaSO4·4CO(NH2)2 adduct.

Keywords: adduct; calcium sulphate; fertilizer; gypsum; phosphogypsum; urea

The influence of mercury content on the structural changes of bioindicator surfaces by Małgorzata Iwona Szynkowska; Aleksandra Pawlaczyk; (pp. 115-120).
This work examines the recommended chemical analytical method for the identification and detecting mercury from the environmental media. The aim of this study was to establish a correlation between mercury content in different biological indicators like: human hair, mushrooms, lichen, moss and needle samples, and the changes in the structure of the investigated material. We have explored the possibilities of using the SEM method in environmental studies to investigate a variety of biological samples coming from areas at different pollution state. We have combined the information from the quantity measurements with the qualitative analysis. The total content of Hg was determined using the Automatic Mercury Analyzer SP-3D. The accuracy of the applied method was verified by an analysis of proper certificate materials: Mixed Polish Herbs INCT-MPH-2, Lichen CRM 482, Pine needles 1575a and Human Hair NCS ZC 81002. The obtained results proved a direct influence of the content of mercury and environmental pollution on the damage of the structure of the studied samples.

Keywords: mercury; surface analysis; bioindicators; SEM

Optimization of chemical aids in the process of deinking sludge thickening by Jacek Czechowski; Konrad Olejnik; (pp. 121-123).
The authors have analyzed a modern technological line of the latest chemicals for the recovered paper processing and de-inking in terms of reducing the amount of wastes arising during the production. The authors have also investigated the effectiveness of selected chemical aids (coagulants and flocculants) supporting the process of sludge dewatering. 12 different types of flocculants were tested. The best chemical agent was selected as well as its optimal dosage. The highest dynamics of sludge dewatering improvement (expressed by the dewatering time under standard conditions) was observed with the ECR3 agent dosage of 6 - 6.5 kg per tonne of the absolutely dry sludge. Long-term analyses of the tested line have proved that the retention aid and its dosage were selected correctly.

Keywords: paper; recovered paper; retention agents; waste; sludge; recycling

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