Evolution of the pathogen content during co-composting of winery and distillery wastes

The aim of this study was to monitor some microbial indicators and pathogen contents (sulphite reducers clostridia, total enterobacteriaceae, total coliforms, faecal coliforms (Escherichia coli), enterococci, Staphylococcus aureus and Salmonella spp.) throughout the co-composting of wastes from the winery and distillery industry with other organic residues, as well as the effect of the composting system used. Seven different piles using mixtures of winery-distillery wastes with other organic materials were prepared. P1 and P2 were made using grape stalk (GS), grape marc (GM), exhausted grape marc (EGM) and sewage sludge (SS), whereas in P3 and P4 were also used exhausted grape marc with cow manure (CW) and poultry manure (PM), respectively, using the Rutgers system. Additionally, P2 was watered with vinasse (V). The rest of piles (P5, P6 and P7) were prepared with grape marc, exhausted grape marc, cow manure and poultry manure, using the turning system. The effectiveness of the composting process to reduce the pathogen content was higher in the static aerated piles than in those elaborated with the turning. The relatively high temperatures (50-60 degrees C) reached in some of the piles produced a notable decrease in some microbial groups, such as total and faecal coliforms (E. coli), but the characteristics of the raw materials used notably influenced the pathogen contents of the end-product.     

Emission of methane and carbon dioxide and earthworm survival during composting of pharmaceutical sludge and spent mycelia

Emissions of methane (CH4) and carbon dioxide (CO2) from spent mycelia of the mold Penicilium notatum and sludge from the effluent treatment facility (ETPS) of a pharmaceutical industry were estimated twice during a two-week composting before vermicomposting. These wastes are dumped in landfills or sometimes used in agricultural fields and no reports are available on their greenhouse gas producing potentials. The solid wastes contained appreciable organic carbon and nitrogen while very high Fe, Mn and Zn were found in ETPS only. Pure wastes did not support germination of Vigna radiata L. while mixing soil with ETPS and spent mycelia at the ratios of 12:1 and 14:1 led to 80% and 50% germination, respectively. The wastes were mixed with cowdung at the ratios of 1:1, 1:3 and 3:1 for composting. Carbon dioxide emissions were always significantly higher than CH4 emissions from all the treatments due to prevalence of aerobic condition during composting. From some treatments, CH4 emissions increased with time, indicating increasing activity of anaerobic bacteria in the waste mixtures. Methane emissions ranged from 21.6 to 231.7 microg m(-2) day(-1) while CO2 emissions were greater than thousand times at 39.8-894.8 mg m(-2) day(-1). The amount of C emitted as CH4-C and CO2-C from ranged from 0.007% to 0.081% of total C composted. Cowdung emitted highest CH4 followed by spent mycelia and ETPS while ETPS emitted more CO2 than spent mycelia but lesser than cowdung. Global warming potential of emitted CH4 was found to be in the range of 10.6-27.7 mg-CO2-equivalent on a 20-year time horizon. The results suggest that pharmaceutical wastes can be an important source of CH4 and CO2 during composting or any other stockpiling under suitable moisture conditions. The waste mixtures were found not suitable for vermicomposting after two weeks composting and earthworms did not survive long in the mixtures.     

Composting winery waste: sludges and grape stalks

The composting of winery waste is an alternative to the traditional disposal of residues, and also involves a commitment to reducing the production of waste products. We studied two residues (sludge and grape stalks), mixed in two proportions (1:1 and 1:2 sludge and grape stalks (v/v)), and we also examined the effects of grinding the grape stalks. Our results showed that composting the assayed materials was possible. Best results were obtained in the compost heap in which the residues were mixed in the proportion 1:2, and where the grape stalks had been previously ground. Optimum results required a moisture around 55% and a maximum temperature around 65 degrees C and an oxygen concentration not lower than 5-10%. The resulting compost had a high agronomic value and is particularly suitable for the soils of the vineyards which have a very low organic matter content. The compost can be reintroduced into the production system, thereby closing the residual material cycle.     

Composting of spent mushroom compost, carnation wastes, chicken and cattle manures

This study has purposed to determine the optimum mixture ratio of used mushroom compost, chicken manure, cattle manure and carnation waste for composting. For this purpose, these materials have been mixed in seven various ratios (R1-R7) and composted in the experimental composting reactors. The highest dry material losses and temperature values have been obtained by the R4 which contains 50% carnation waste, 25% chicken manure and 25% spent mushroom compost. Beside R4, mixtures of R2, R5 and R6 have also provided high process temperature and dry material loss values. The lowest dry material loss and temperature values have been obtained in the R7 which contains only carnation wastes. In the study, it has also seen that FAS (free air space) parameter is effective on the process and must be in the interval of 24-32%.     

The study of the aerobic bacterial microbiota and the biotoxicity in various samples of olive mill wastewaters (alpechin) during their composting process

Five different piles were prepared by mixing olive mill wastewater (alpechin) and alpechin sludge with two bulking agents (cotton waste and maize straw) and two organic wastes with high content of nitrogen (sewage sludge and poultry manure), which were composted by the Rutgers static pile composting system in a pilot plant. The aim of this work was to study the evolution of total nitrogen and different forms of organic matter and evaluate the variation in the aerobic bacterial microbiota present and biotoxicity during the composting process.In piles prepared with alpechin, the use of the maize straw as a bulking agent reduced the nitrogen losses whereas the use of sewage sludge, instead of poultry manure, with cotton waste originated the highest degradation of organic matter. In piles prepared with alpechin sludge a similar evolution of the composting process was observed. There were not great variations during composting in the aerobic bacterial microbiota present in the mixtures. However, the pile prepared with alpechin sludge and maize straw was only one to present bacteria capable of growing in alpechin, and the toxicity study showed that this was only present in the starting mixtures.     

Chemical,Thermal and Spectroscopic Methods to Assess Biodegradation of Winery-Distillery Wastes during Composting

The objective of this work was to study the co-composting process of wastes from the winery and distillery industry with animal manures, using the classical chemical methods traditionally used in composting studies together with advanced instrumental methods (thermal analysis, FT-IR and CPMAS ¹³C NMR techniques), to evaluate the development of the process and the quality of the end-products obtained. For this, three piles were elaborated by the turning composting system, using as raw materials winery-distillery wastes (grape marc and exhausted grape marc) and animal manures (cattle manure and poultry manure). The classical analytical methods showed a suitable development of the process in all the piles, but these techniques were ineffective to study the humification process during the composting of this type of materials. However, their combination with the advanced instrumental techniques clearly provided more information regarding the turnover of the organic matter pools during the composting process of these materials. Thermal analysis allowed to estimate the degradability of the remaining material and to assess qualitatively the rate of OM stabilization and recalcitrant C in the compost samples, based on the energy required to achieve the same mass losses. FT-IR spectra mainly showed variations between piles and time of sampling in the bands associated to complex organic compounds (mainly at 1420 and 1540 cm^-1) and to nitrate and inorganic components (at 875 and 1384 cm^-1, respectively), indicating composted material stability and maturity; while CPMAS ¹³C NMR provided semi-quantitatively partition of C compounds and structures during the process, being especially interesting their variation to evaluate the biotransformation of each C pool, especially in the comparison of recalcitrant C vs labile C pools, such as Alkyl /O-Alkyl ratio.     

Nitrogen transformation during organic waste composting by the Rutgers system and its effects on pH, EC and maturity of the composting mixtures

The evolution of the different forms of nitrogen during the composting of several wastes was studied, as well as its relation to the pH, electrical conductivity and parameters of maturity of the composts obtained. Four mixtures were prepared from different organic materials: sewage sludge, municipal solid waste, brewery sludge, sorghum bagasse, cotton waste and pine bark. The evolution of the different forms of nitrogen during composting depended on the material which supplied the nitrogen to the mixtures and the organic matter (OM) degradation rate during composting. The greatest concentration of ammonium was observed during the first weeks of composting, coinciding with the most intense period of OM degradation, and ammonium then decreased gradually to reach final values of below 0.04%. The use of urea as a nitrogen source in the mixtures led to high ammonium levels during the first weeks as a result of its rapid hydrolysis. The nitrification process began only when the temperature of the mixtures had dropped below 40 degrees C and its intensity depended on the quantity of ammonium present when the process began. The highest concentrations of NO3-N were always produced at the end of maturation, reaching values of 0.52%, 0.53%, 0.12% and 0.20% in the four mixtures studied. Nitrogen losses during composting depended on the materials used and on the pH values of the mixtures. Mixtures with the highest lignocellulose content showed the lowest losses (below 25%), while those containing municipal solid waste lost more than 40% of the initial content. Statistically significant correlations at a high probability level were found between the NO3-N concentration and pH and electrical conductivity. confirming that nitrification was responsible for the falling pH values and increasing electrical conductivity. The ratio of NH4-N and NO3-N concentrations was shown to be a clear indicator of the maturity of the mixtures during composting, the final values of 0.08, 0.04, 0,16 and 0.11 for the four mixtures being equal to, or below the maximum value established as a maturity index in other materials.     

A low-cost procedure for production of fresh autochthonous wine yeast

A low-cost procedure was designed for easy and rapid response-on-demand production of fresh wine yeast for local wine-making. The pilot plant produced fresh yeast culture concentrate with good microbial quality and excellent oenological properties from four selected wine yeasts. The best production yields were obtained using 2% sugar beet molasses and a working culture volume of less than 60% of the fermenter capacity. The yeast yield using 2% sugar grape juice was low and had poor cell viability after freeze storage, although the resulting yeast would be directly available for use in the winery. The performance of these yeasts in commercial wineries was excellent; they dominated must fermentation and improved its kinetics, as well as improving the physicochemical parameters and the organoleptic quality of red and white wines.     

Kinetics of sequential nitrification and denitrification processes

Kinetics of nitrification and denitrification of synthetic wastewater was investigated by using two reactors in series. An activated sludge unit was used for nitrification followed by a downflow biofilter for denitrification. Glucose solution was fed to the denitrification column to supply carbon source. Reactors were operated at different operating conditions and data were collected for determination of kinetic constants. Experimental data indicated that nitrification and denitrification kinetics followed Monod kinetics. By using the experimental data, kinetic constants for nitrification were determined as k = 1.15 d(-1), K(N) = 5.14 mg/l, Y = 0.34 mgX/mgN and b = -0.021 d(-1). Similarly, kinetic constants for denitrification were determined as k = 0.23 d(-1) and K(DN) = 0.27 mg/l. Rates of nitrification and denitrification increased with increasing nitrogen loading rate.     

Humic substances change during the co-composting process of municipal solid wastes and sewage sludge

The change of the degree of stability of compost during the composting process was a kind of guideline for our study. This stability was estimated by monitoring the chemical fractionation (extraction of humic and fulvic acids, and humin) during two cycles of composting. Change of humin (H), humic-like acid carbon (CHA) and fulvic-like acid carbon (CFA) fractions during the composting process of municipal solid wastes were investigated using two windrows W1 (100% of municipal solid wastes) and W2 (60% of municipal solid wastes and 40% of dried sewage sludge). Humin and fulvic acid fractions in the two windrows decreased since the start of composting process and tend to stabilize. At the end of composting process, humic acid fraction is more important in the windrow without sludge (W1) than the one with sludge (W2). The humification indexes used in this study showed that the humic-like acid carbon fraction production takes place largely during the phase of temperature increase (thermophilic phase), and it appeared very active in the windrow W2. At the end of composting process, the E₄/E₆ ratio value indicated that the compost of W1 is more mature than the compost of W2. The humification ratio (HR) allowed a correct estimation of compost organic matter stabilization level.     

Enhancing the co-composting of olive mill wastes and sewage sludge by the addition of an industrial waste

In this work, the effect of incorporating an acidic ferrous sulphate waste (SF) over co-composting process of sewage sludge and olive mill solid wastes in a 1:2 v/v wet basis was investigated. The SF used was an industrial by-product of titanium oxide synthesis and its addition resulted in a chemical stabilisation of the wastes at low pH. The optimum dose of SF to enhance the composting of the studied biowastes was a 20% v/v (wet basis) and the best moment for the addition turned out to be whenever the composting piles had achieved the thermophilic range. The addition of SF over the composting process made possible a faster stabilisation, increasing the composting rate from 0.033 to 0.13 d(-1), and leading to a Fe and S rich compost. All composts obtained fulfilled the limits determined by current European and Spanish regulations and presented better characteristics for its use as soil amendment and organic fertilizer than the traditional composts without SF. The optimum dose of compost containing SF was determined through agronomic tests being its value about 18 Ton ha(-1).     

Determination of aeration rate and kinetics of composting some agricultural wastes

This study aimed to determine the aeration rate and its kinetics in aerobic composting of agricultural wastes. For this aim compost materials were prepared by mixing grass trimmings, tomato, pepper, and eggplant wastes. Four vertical forced aeration type reactors and one vertical natural convection type reactor were manufactured to apply four different aeration rates. CO2 rate and temperature changes were recorded in three different places in the reactors. Moisture content, pH and organic material rate were recorded each day. While process-monitoring parameters (CO2, temperature, pH, moisture content) were used for interpretation of the process, organic material degradation was used for interpretation of the process success. The seven different kinetic models were applied for modeling decomposition rate to the experimental values. According to the results, four of these models were found applicable to this study. These models were analyzed with some statistical methods as root mean square error (RMSE), chi-square (chi2), and modeling efficiency (EF). According to the statistical results of these models, the best model was found as: [Formula: see text] where kT is the rate of decomposition (g VS/g VS day); T the process temperature (degrees C); Mc the daily moisture content (%wb); C the daily CO2 rate in composting reactor (%) and a, b, c, d are constants. According to the results, the highest organic matter degradation and temperature value were obtained at the aeration rate of 0.4 l air min(-1)kg(om)(-1). Thus, it could be applied to this mixed materials composting process.     

Effect of the raw materials and mixing ratio of composted wastes on the dynamic of organic matter stabilization and nitrogen availability in composts of Sub-Saharan Africa

The effect of raw materials and their proportions in initial mixtures on organic matter (OM) stabilization and nitrogen (N) availability during pit composting in Sub-Saharan Africa was assessed using biochemical fractionation and laboratory incubations to characterize composts sampled throughout the composting process. Stabilization of OM occurred more rapidly in mixtures with slaughter-house wastes, it was progressive in mixture with household refuses while tree leaves compost remained unstable. Carbon mineralization from compost samples was positively correlated to water soluble and hemicellulose-like organic fractions. Mixtures containing large proportions of household refuses reached the highest stability and total N but available N remained weak. Slaughter-house wastes in the initial mixtures made possible to reach good OM stabilization and the largest N availability. The nature of initial mixing influenced composting parameters, OM stabilization and N availability. It is suggested mixing household refuses and slaughter-house wastes with tree leaves to reach better amending and fertilizer qualities of composts.     

An LCA study on sludge retreatment processes in Japan

The majority of night soil (human excrements) is source separated from other sewage water and treated at night soil treatment plants in Japan. Efforts have been made to achieve material recovery from this organic mass, together with other organic wastes such as kitchen wastes and manure, by expanding the functions at night soil treatment plants. These facilities with expanded function are called ‘sludge retreatment centers’, which are promoted by the Japanese Ministry of Health and Welfare. Potential environmental impacts of sludge retreatment using two presently available systems in Japan are analyzed for comparison. Systems compared are: 1) Mebius system, a high-speed fermentation process with methane gas recovery and compost production and 2) a comparable system with a basic composting process. The functional unit for this study is concurrent treatment of 40 t/d of kitchen waste, 40 m³/d of night soil, and 60 m³/d of private sewage treatment tank sludge. Impact assessment on Global Warming (IPCC 1996, 20 yrs.), Acidification Potential (De Leeuv — AP), Eutrophication Potential (De Leeuv- EP) and Resource Index (Fava/SETAC & Heijungs) all indicated that sludge retreatment with Mebius system provides a better environmental performance. The main reasons are: 1) production of power using recovered methane and 2) reduction of sludge volume by digestion, which leads to reduction of fuel required for sludge drying. The collection and treatment of night soil and kitchen wastes involves many economic and social factors. Therefore, more studies with different functional units on these systems should be made to obtain a more complete picture that can be used for decision-making processes. The results of this study can be used as a starting point.     

Pile settlement and volume reduction measurement during forced-aeration static composting

In this study, a settlement measurement device was used to track the settlement of different layers in composting piles, and time courses of settlement velocity, bulk density distribution, and effective bulk density were investigated. Settlement is divided into two stages: the physical compressive settlement and the mass loss settlement. At the end of the former stage, bulk density (rho') and pile height (h) follow rho'=Ah(B), where A is a fitting parameter for the initial bulk density of the composting material, and B is the compression parameter. The physical compressibilities of composting mixtures are night-soil sludge and garden refuse (1:1) >sewage sludge and cornstalks (5:4) >night-soil sludge and garden refuse (2:3) >sewage sludge and bark (1:1). Adding the proportion of bulking agent in the proper extent effectively retarded composting settlement. Bark exhibits a better supporting capability than cornstalk does as a bulking agent.     

Estimation of cadmium availability using transformed roots

We have explored cultures of roots transformed by Agrobacterium rhizogenes to test the availability of cadmium in sewage sludges. The toxic effects of Cd and the kinetics of Cd accumulation were examined for three species of transformed roots, grown for 2 weeks in nutrient media, containing Cd as a salt. Roots of sugar beet (Beta vulgaris L.) were highly sensitive, while those of tobacco (Nicotiana tobaccum L.) and morning glory (Calystegia sepium R. Br) were more tolerant. Cd accumulation was higher in sugar beet and morning glory than in tobacco. We developed a non-sterile, 5-day procedure for testing the accumulation (an indication of availability) of Cd from sludge suspensions, using transformed roots of morning glory and tobacco. Cd accumulation varied with plant species and source of sludge. Ranking of Cd availability using this biological assay for Cd accumulation was confirmed by chemical tests with NH₄ acetate and EDTA. Results from transformed roots were also compared with those from normal, excised, tobacco roots and normal and transformed tobacco plantlets. No major alteration in Cd uptake was associated with genetic transformation. We thus demonstrated the feasibility of using transformed roots to estimate the availability of Cd in metal-contaminated materials like sewage sludges.     

河西走廊不同产地‘赤霞珠’酿酒葡萄果实品质评价

为了确定河西走廊地区‘赤霞珠’酿酒葡萄核心品质指标,建立‘赤霞珠’酿酒葡萄品质综合评价模型。从张掖、武威、嘉峪关3个酿酒葡萄主产市的代表性果园采集6份‘赤霞珠’葡萄样品进行品质测定,通过主成分分析和聚类分析法确定‘赤霞珠’葡萄核心品质指标,运用层次分析法确定指标权重并建立‘赤霞珠’葡萄品质综合评价模型。结果表明:(1)不同产地‘赤霞珠’酿酒葡萄品质指标存在明显差异性,张掖市国风葡萄酒庄园的‘赤霞珠’葡萄果糖、蔗糖、草酸、柠檬酸含量均高于其他地区,且可溶性固形物、可溶性糖、总酚、苹果酸含量在各产地中也均保持在最高水平。(2)相关性分析发现,葡萄果实葡萄糖含量与可溶性固形物含量、果糖与可溶性糖含量之间呈极显著正相关,固酸比和糖酸比均与可滴定酸含量呈极显著负相关关系。(3)综合主成分分析、聚类分析和相关性分析结果,确定维生素C(Vc)、单宁、果糖和固酸比是‘赤霞珠’葡萄核心品质指标,应用层次分析法建立了‘赤霞珠’葡萄品质综合评价模型为Y=0.0960×Vc含量+0.1611×单宁含量+0.2771×果糖含量+0.4568×固酸比(各指标含量均经过标准化处理)。研究发现,河西走廊地区‘赤霞珠’葡萄果实品质最佳产地是张掖市,果实Vc、单宁、果糖和固酸比是‘赤霞珠’葡萄的核心品质指标,以其建立的评价模型可用于‘赤霞珠’葡萄品质的综合评价。     

The vinification of partially dried grapes: a comparative fermentation study of Saccharomyces cerevisiae strains under high sugar stress

AIMS: The study of the fermentation performance of Saccharomyces cerevisiae strains under high sugar stress during the vinification of partially dried grapes. METHODS AND RESULTS: Microvinification of partially dried grape must with sugar concentration of 35 degrees Brix was performed using four commercial strains to carry out alcoholic fermentation. A traditional red vinification without nutrients addition was applied. Yeasts displayed different efficiency to convert sugar in ethanol and varied in glycerol yield. Sugar consumption and ethanol level were attested at 80-87% and 143.5-158.0 g l(-1) respectively. High correlation between sugar and assimilable nitrogen consumption rate was observed. Statistical treatment of data by principal component analysis highlighted the different behaviours that strains exhibited in regard to the production of higher alcohols and other compounds important to wine quality. CONCLUSIONS: Saccharomyces cerevisiae strains displayed appreciable capability to overcome osmotic stress and to yield ethanol fermenting high sugar concentration grape must in winemaking condition. SIGNIFICANCE AND IMPACT OF THE STUDY: The results provided insights on the strain contribution to wine quality subordinate to stress condition. This investigation is of applicative interest for winemaking and processing industry that use high sugar concentration musts.     

Evolution of the fulvic acid fractions during co-composting of olive oil mill wastewater sludge and tree cuttings

Fulvic acids (FAs) were isolated by a conventional procedure from two mixtures of the sludge residue obtained from olive oil mill wastewater (OMW) evaporated in open-air pond and tree cuttings (TC) at different stages of the co-composting process. The FAs were analyzed for elemental (C, H, N, S, O) and acidic functional group (carboxylic and phenolic) composition, and by ultraviolet/visible, Fourier transform infrared and fluorescence spectroscopies. At the initial stage of composting, FAs from the OMW sludge-TC mixtures were characterized by a prevalent aliphatic character, large contents of C, S-containing groups, proteinaceous materials and polysaccharide components, extended molecular heterogeneity, small O and acidic functional group contents, and small degrees of aromatic ring polycondensation, polymerization and humification. As composting proceeded, C, H and S contents, C/N ratio, and aliphaticity decreased, whereas N, O, COOH and phenolic OH contents, C/H and O/C ratios, and aromaticity increased. These results suggested that, with increasing the composting time, the chemical and structural properties of the FA components of the two OMW sludge-TC mixtures approached the characteristics typical of native soil FAs. Thus, co-composting of OMW sludge mixed with TC may represent a suitable treatment for enhancing the quality of organic matter in these materials when used as soil amendments.     

Possibilities of the use of vinasses in the control of fungi phytopathogens

The purpose of this research was to study the biocide effect of three agroindustrial subproducts, concretely sugar beet, sugar cane and wine vinasse. Results from in vitro testing determined that wine vinasse is what shows a 100% capacity to suppress fungal growth with concentrations between 5% and 7% for Fusarium oxysporum f.sp. melonis race 0 and 1, Sclerotinia sclerotiorum, Pythium aphanidermatum and Phytophthora parasitica and 10-15% for F. oxysporum f.sp. radicis-cucumerinum. On the other hand, sugar cane vinasse produced an increase at high concentrations and sugar beet vinasse showed an approximate 100% suppressor effect on fungal growth for only some of the phytopathogens tested: S. sclerotiorum (15%), P. aphanidermatum (7%), P. parasitica (15%) and F. oxysporum f.sp. radicis-cucumerinum (15%). In the soil samples analyzed none of the three vinasse extracts decreased fusaric microbiota, producing an increase in the three samples tested. This would implicitly convey an improvement in soil quality by producing a potential increase in bacterial and fungal microbiota.