Characterization of Wastes from Olive and Sugarbeet Processing Industries and Effects of Their Application upon the Organic Fraction of Agricultural Soils

Abstract

The lipidic fraction compositions of both concentrated vinasses, a by-product of the sugar industry, and a compost made basically from olive oil vegetation waters (alpechin) were studied. The alpechin lipids are composed mainly by series of n-alkanes and lineal and branched fatty acids, whereas the major lipids in vinasses were n-alkanes, n-alkanols and acetals. Concentrations and composition of lipids in both materials do not seem of concern.

Preliminary results on the effects of the application of both materials over two years on the organic status of an agricultural soil are also reported. No significant changes were observed in total organic carbon and contents in humic fractions and lipids before and after the applications. However, analysis by GC-MS of the lipid compounds present in bound forms in the subsoil layer revealed that some hydrophobic components were accumulated in the soil following the waste applications.     

Quantitative Analysis of Carbon-14 Labelled Polychlorinated Biphenyls and Hexachlorobenzene in Biological Samples Using an Oxidative Combustion Method

Abstract

Carbon-14 labelled glucose, polychlorinated biphenyls, and hexachlorobenzene at concentrations of 0.01-1200 nanograms were oxidized in a combustion chamber at 900C. The ¹⁴CO₂ emitted was trapped in an organic base. and its radioactivity measured. Recovery rates of 95-104% were obtained from samples oxidized with mannitol, while recoveries of samples oxidized with dried fish ranged from 93—101%. This method provides an alternate technique of sample preparation for materials that may yield a highly quenched solution following conventional sample preparation procedures for liquid scintillation measurements.     

Development of Flow Analytical Systems for Monitoring Thiocyanate Biodegradation in Waste Waters

ABSTRACT

Metallurgical waste waters have a very complex composition. Different reactions take place in such waters. Among them, the reaction of pyretic materials with free cyanide results in the production of thiocyanate, another hazard to the aqueous media. Biological cleanup (bioremediation) is one of the methods to eliminate SCN of waste waters and, consequently, it is necessary to develop sensitive and convenient methods for thiocyanate analysis in this bioprocess in order to assure environmental quality control.

In the work presented here different spectrophotometric flow systems based on the reaction between Fe(III) and SCN are studied to control thiocyanate in crude and biologically treated coke plant waster waters, using a conventional flow cell and a fibre optical continuous flow system. Chemical and physical parameters of the flow systems were studied. A simple, fast and sensitive continous flow system with optical fibres is proposed for monitoring thiocynate degradation in a waste water biological reactor.     

Characterization of Sediments in Aerated Lagoons and Waste Stabilization Ponds

Abstract

Sediments affect the performance of aerated lagoons and waste stabilization ponds in many ways. This paper presents the results of a three years study conducted on real-size facilities and implementing numerous analytical procedures. Sediment accumulation rates and physico-chemical characteristics are described as well as their activity in terms of oxygen consumption and exchange rates with overlying waters.

The deposits had a mean accumulation rate of 4.7 cm per year, their main characteristics being low viscosity and high organic content (>30%). They also accumulated numerous organic and mineral compounds, such as nutrients and heavy metals. Vertical concentration profiles, measured in the sediment and interstitial liquid phases, are presented and discussed. These results emphasize the importance of surface activity.

Sediment oxygen demand, which can be divided into biological and chemical components, ranged from 1 to 3 gO₂/m²·d. Finally, the exchange rates of COD, nitrates, ammonia and orthophosphates existing at sediment-water interface were quantified under several redox conditions and substrate additions.     

Characterization and pyrolysis behaviour of different paper mill waste materials

Paper industry generates a considerable amount of wastes. Their composition mainly depends on the type of paper produced and the origin of cellulose fibres. Nowadays, in Spain, 40% of solid wastes generated by the paper and pulp industry are deposited directly in landfill, 25% are used in the agriculture, 13% in the ceramic industry and 7% in the concrete production. In the last years, thermal treatment methods like combustion, pyrolysis and gasification have been widely study as alternative techniques for the valorization of different organic waste materials. The main objective of the present work is to study the pyrolysis behaviour of different paper mill waste materials. For this reason, a wide characterization of eight paper mill waste materials from different origins was performed using SEM, FTIR, DRX and thermogravimetric techniques. Paper mill sludges from recycled paper, mainly wastes obtained from deinking process, showed high CaCO₃ and clays contents. Compared with the elevated total organic matter content (TOM) of paper mill waste materials their low organic carbon content determined by Cr₂O₇²⁻ oxidation reveals the elevated chemical stability of organic matter, due to high content on cellulose fibres. Analysis of samples by SEM indicates that successive recycled processes of paper leads to paper mill waste materials with more degraded fibres. XRD analyses show as crystalline cellulose was present in reject and primary sludge from paper mills that produced paper from virgin wood. However, crystalline cellulose content significantly decreased in waste materials from recycled paper. Finally, thermogravimetric analysis indicates that presence or mineral matter and degradation of cellulose significantly influences their pyrolysis behaviour. In general, weight loss of paper mill waste materials started at lower temperatures than pure cellulose. In waste materials from recycled paper weight loss continues at temperatures highest than 500 °C due to kaolinite dehydration and carbonates decomposition.     

Industrial wastewater treatment wastes used as oxygen carriers in energy generation processes

The paper contains the results of a study on a promising combustion technology known as chemical looping combustion (CLC). The main advantage of CLC is the production of a highly concentrated CO₂ stream without any energy penalty for its separation, together with NO_x emissions reduction. The objective of this work was to examine novel oxygen carrier (OC) materials for their practical applications with gaseous fuel/air. We report a simple, economical and environmentally friendly method for the large-scale synthesis of OCs from wastes. The reactivity tests for OCs made from wastewater from a coking plant were performed in a thermogravimetric analyser. For selected temperatures, reduction–oxidation cycles were performed. The effect of temperature on the reaction rates, the effect of waste treatment and the oxygen transport capacity were determined. The waste material demonstrated good thermal stability and maintained its redox behaviour over cycling. ICP-OES and XRD data revealed these materials that contained beneficial amounts of Fe species and silicon oxide, which improved stability. The study showed that these waste materials are excellent examples of raw materials that can enable a decrease in OC production costs with the additional benefit of the practical management of post-wastewater sediments from coke oven wastewater plants.

     

Assay of Sulfur in Organic Liquids Using a Mercury Displacement Method

Abstract

A method for the assay of sulfur in organic liquids is presented. The method utilizes an oxidative combustion process coupled with a piezoelectric crystal detector. The sulfur dioxide evolved upon combustion of the organic liquid is bubbled through a mercurous nitrate solution. The mercury vapor produced is detected by a piezoelectric crystal due to the formation of a mercury amalgam.     

HUMIC MACROMOLECULES IN NATURAL WATERS

Abstract

Humic substances are the major organic constituents of soils and sediments. They also occur in small concentrations in natural surface waters and groundwaters. They form through the breakdown of plant and animal tissues by chemical and biological processes that tend to produce complex chemical structures that are more stable than the original material from which they were derived. One of the more important characteristics of humic substances is their ability to form water-soluble and water-insoluble complexes with metal ions and hydrous oxides and to interact with clay minerals and various organic compounds such as alkanes, fatty acids, and toxic organic substances such as pesticides.     

Biomaterials from beer manufacture waste for bone growth scaffolds

Abstract

Agricultural wastes are a source of renewable raw materials (RRM), with structures that can be tailored for the use envisaged. Here, they have proved to be good replacement candidates for use as biomaterials for the growth of osteoblasts in bone replacement therapies. Their preparation is more cost effective than that of materials presently in use with the added bonus of converting a low-cost waste into a value-added product. Due to their origin these solids are ecomaterials.

In this study, several techniques, including X-ray diffraction (XRD), chemical analysis, mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM), and bioassays, were used to compare the biocompatibility and cell growth of scaffolds produced from beer bagasse, a waste material from beer production, with a control sample used in bone and dental regenerative processes.     

Removal of chromium from water using pea waste – a green approach

Abstract

Agro-waste materials have carboxylic and phenolic groups that play the main role in metal adsorption. The advantages of these materials include easy availability, low cost, and reasonable metal removal capacity. One of the materials (usually considered as waste) is pea waste (pods). Present work comprises adsorption of chromium from aqueous solution using powder of pods of garden peas (Pisum sativum) in batch. Important parameters like adsorbent dose, pH, contact time, and agitation speed were studied. Adsorption equilibrium was explained by Langmuir, Freundlich, and Temkin isotherms. Maximum chromium uptake (q _m) was 3.56 mg/g of adsorbent. Heat of adsorption, as evaluated by Temkin isotherm was 1.96 kJ/mol. It is proposed that pea pods can be an effective and environmentally benign (green) adsorbents for removal of chromium from industrial effluents and waste waters.     

Sample and Sorbent Integrity During Combustion Source Sampling

Abstract

A research program was initiated to evaluate the stability of selected organic compounds collected on porous polymer sorbents during combustion source sampling. This type of study is necessary to determine if destruction and removal of hazardous materials waste has occurred during incineration and not as a result of the sampling and analytical approach used. Two compounds, hexachlorobenzene and toluene diisocyanate, were selected for study. Due to difficulties encountered in preliminary work, studies on toluene diisocyanate were discontinued. Hexachlorobenzene sorbed onto XAD-2 resin at the 1 μg level was exposed to the following conditions intended to simulate hazardous waste incineration stack samplin: moist air, moist air in combination with HCl (two concentrations), and warm air. Recoveries following exposure were determined for each of three trials. The results indicate that hexachlorobenzene sorbed onto XAD-2 is stable with respect to the conditions routinely encountered during incineration stack sampling.     

Flow Injection Analysis Using Potassium Permanganate: An Approach for Measuring Chemical Oxygen Demand in Organic Wastes and Waters

Abstract

A rapid and continuous analytical method based on flow injection analysis was developed for the determination of chemical oxygen demand due to organic substances in water pollution. Potassium permanganate and sulfuric acid solutions were individually pumped up as an oxidizing agent and glucose was used as a standard substance. The results for filtered organic waste and water samples were as reasonable as compared to those measured by the manual acidic permanganate method.     

Electrochemical monitoring of plastic artefacts degradation

Abstract

Plastic materials are being used in art: in Italy, for instance, two Art Museums are already presenting only plastic artefacts. As organic matter, plastic suffers degradation and chemical and biological attacks beyond obvious ageing process. Here, we propose an electrochemical approach aiming at the evaluation of the conditions of a plastic object, so giving the opportunity of protection and conservation strategies. The method is very cheap, easy to be handled and absolutely non-invasive, and is based on the monitoring of acidity emitted by a degrading plastic basing on corrosion potential of target metals acting as sensors.     

Vertical Mobility of Soil Contaminants: Preliminary Results of a Survey on the Herbicide Atrazine

Abstract

Atrazine is considered a potential contaminant of water bodies, where it has been repeatedly detected. Its use in Italy is almost limited to the Northern part of the country where corn monocultures are common. Northern Italy is characterized by the presence of an area with soil quite permeable and where ground waters are often present at not very deep levels. In this area well waters, which represent the main source of drinking water, have been frequently found contaminated by atrazine. A program has been started aimed at studying the role of soil nature and local factors in the process of groundwater contamination. Two atrazine application rates were used at two sites with loamy and loamy-sandy soils. Results clearly show a different mobility of atrazine in the two soil types. Since the two sites have similar organic carbon levels, the major proportion of clay to sand and the lower pH of loamy soil may explain the lower vertical mobility of atrazine in this soil. Work is in progress to study atrazine behaviour to a soil depth of 30cm and the effect of repeated atrazine applications on ground water pollution.     

Professor Eduardo F. A. Neves (1933–2006)

Abstract

The present note deals with the optimization of the combustion of organic materials to CO₂ in Pyrex and quartz tubes. The influence of temperature and oxidant on the combustion yield was investigated. Different physical forms of CuO and a CuO/MnO₂-mixture were used as oxidants. Possible isotopic effects during combustion were tested by gas isotope ratio mass spectrometry (GIRMS) of the CO₂. Excellent results were obtained for combustion in Pyrex at 530 °C using CuO rods mixed with 20% MnO₂ as oxidant. The stable isotope results for CO₂ prepared with this method were accurate and showed a very good precision of 0.030 %. Applications for which quantitative combustion is a necessity, we suggest the use of CuO powder (< 100 μm) as oxidant and a combustion temperature of 850 °C.     

Study of adsorption phenomena ongoing onto clinoptilolite with the immobilized interfaces

The development of innovative clean-up technologies remains a challenge as current procedures have many limitations, such as being expensive, concentration or pollutant specific, and many others. Natural zeolite of clinoptilolite type was beneficiated with surfactant octadecylammonium and alginate biopolymers using the sol-gel method. Carbonization process in pyrolysis chamber combusted organic waste materials and reaching the maximum temperature of 700°C was used for the surface carbonization, respectively. Resulted zeolite based products were analyzed by FTIR, TG, DTA and examined on the selected aqueous pollutants removal using the conventional laboratory adsorption experiments. The ability of ODA and alginate linked zeolite of clinoptilolite type to form complexes with anions (such as nitrate, sulphate, chloride and phosphate) and to remove them from contaminated waters was validated. Carbon deposition onto clinoptilolite surface originated from the pyrolytic carbon-rich waste combustion simulated the new zeolite based hybrid to active coke, adsorption efficiency of which towards phenol was approved. Thermogravimetric analyses of the advanced zeolite-based adsorbents were accomplished to find out how temperature resistant are the novel zeolite based materials in respect to the original, untreated one. While the native clinoptilolite indicated according to DTA analysis one broad endothermic response around 100–130°C, resulted from the loss of adsorbed water, by the ODA-modified clinoptilolite was except this DTA peak, the broad exothermic response started from 370 up to 560°C observed. This DTA profile is assumed to record a slowly breakdown of attached ODA surfactant and sequential loss of mass due to continual heating of sample under elevated temperature.     

A New Approach for the Determination of Organobromine in Harmful Waste

Determination and estimation of organic sulphur, nitrogen, phosphor and halides in harmful chemical waste and estimation of emission of SO₂, NO_X, HCI, HBr or HI during incineration are the primary task of risk assessment. In our paper we present a new analytical approach for determination of bromine in a heterogeneous sample. The method applied is based on combustion of chemical waste under oxygen atmosphere (pressure 20 bars) and transformation to corresponding anions. These anions can be measured by ion chromatography. Using this method all hetero atoms can be transformed to corresponding anions (except for oxygen) and can be measured by ion chromatography. In this paper we report of determination of bromine content of chemical waste. During the combustion of organobromine compounds different types of inorganic bromine are formed. All types of bromine must be converted to Br^–. To fulfil it the above, ascorbic acid solution was used for absorbing and transforming all types bromine compounds to Br^–. We will discuss all the details about this new approach and give all the parameters to get efficient conversion from organic bromine to bromide anions.This revised version was published online in November 2005 with corrections to the Cover Date.     

A solid composite electrode for the determination of the electrochemical oxygen demand of aqueous samples

A composite electrode containing graphite, paraffin, AgO and CuO is described for the determination of the electrochemical oxygen demand (EOD) of waste waters. The oxidation of dissolved organic compounds at the electrode is based on a heterogeneous chemical reaction of AgO/CuO with the organic constituents of the waste water. This chemical reaction can be followed by a solid state electrochemical oxidation of the formed Ag₂O/Cu₂O. The method has been tested with various organic compounds and applied to real samples of sewage water. The EOD values correlate well to BOD and COD values.     

Daily Variations in Composition of Extractable Organic Compounds in Fly-Ash from Municipal Waste Incineration

Abstract

The daily variations of organic compounds on fly ash from municipal waste incinerator are reported. Variations in composition over a one week sampling period were 1 to 8 μg/g for estimated total organic compounds, 57 to 220ng/g for total polychlorinated dibenzo-p-dioxins, and 56 to 490ng/g for total polycyclic aromatic hydrocarbons.     

Matrix Effects in Determination of Triazines and Atrazine Metabolite in Waters with Solid‐Phase Extraction Followed by High Performance Liquid Chromatography Coupled with Tandem Mass Spectrometry

Abstract

A method for determination of selected triazines in waters was developed. The method includes off‐line solid‐phase extraction of triazines on the polymeric sorbent, high‐pressure liquid chromatographic separation, and determination with tandem mass spectrometer. The linearity extended from 0.008 to 1.000 µg L^?1 for each triazine while the limits of detection ranged from 0.001 to 0.004 µg L^?1. Solid‐phase extraction recoveries from ground, surface, and waste waters ranged from 64% to 96%. Possible water interferences were investigated. Natural humic acids and salts did not influence the ionization process. The presence of humic acids did not affect binding ability of the solid‐phase sorbent, while the presence of salts increased the extraction efficiency by approximately 10%.