An integrated mathematical model for co-composting of agricultural solid wastes with industrial wastewater

An integrated model for the composting process was developed. The structure of the model is such that it can be implemented in any mixture of different substrates, even in the case of co-composting of a solid waste with industrial wastewater. This paper presents a mathematical formulation of the physicochemical and biological principles that govern the composting process. The model of the co-composting ecosystem included mass transfer, heat transfer and biological processes. The biological processes included in the model were hydrolysis of particulate substrates, microbial growth and death. Two microbial populations (bacteria and fungi) were selected using Monod kinetics. Growth limiting functions of inhibitory factors, moisture and dissolved oxygen were added in the Monod kinetics. The bacteria were considered to utilise the easy biodegradable carbon hydrolysis product, fungi the difficult one, while both could degrade the carbon of wastewater. The mass balances of the most important nutrients, nitrogen and phosphorous, were also included in this approach. Model computer simulations provided results that fitted satisfactory the experimental data. Conclusively, the model could be a useful tool for the prediction of the co-composting process performance in the future and could be used to assist in the operation of co-composting plants.     

Low-molecular-weight components of olive oil mill waste-waters

A new lignan 1-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-6-(3-acetyl-4-hydroxy-5-methoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane, the secoiridoid 2H-pyran-4-acetic acid,3-hydroxymethyl-2,3-dihydro-5-(methoxycarbonyl)-2-methyl-, methyl ester, the phenylglycoside 4-[beta-D-xylopyranosyl-(1-->6)]-beta-D-glucopyranosyl-1,4-dihydroxy-2-methoxybenzene and the lactone 3-[1-(hydroxymethyl)-1-propenyl] delta-glutarolactone were isolated and identified on the basis of spectroscopic data including two-dimensional NMR, as components of olive oil mill waste-waters. The known aromatic compounds catechol, 4-hydroxybenzoic acid, protocatechuic acid, vanillic acid, 4-hydroxy-3,5-dimethoxybenzoic acid, 4-hydroxyphenylacetic acid, 3,4-dihydroxyphenylacetic acid, tyrosol, hydroxytyrosol, 2-(4-hydroxy-3-methoxy)phenylethanol, 2-(3,4-dihydroxy)phenyl-1,2-ethandiol, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, 1-O-[2-(3,4-dihydroxy)phenylethyl]-(3,4-dihydroxy)phenyl-1,2-ethandiol, 1-O-[2-(4-hydroxy)phenylethyl]-(3,4-dihydroxy)phenyl-1,2-ethandiol, D(+)-erythro-1-(4-hydroxy-3-methoxy)-phenyl-1,2,3-propantriol, p-hydroxyphenethyl-beta-D-glucopyranoside,2(3,4-dihydroxyphenyl)ethanol 3beta-D-glucopyranoside, and 2(3,4-dihydroxyphenyl)ethanol 4beta-D-glucopyranoside were also confirmed as constituents of the waste-waters.     

香梨优斑螟飞行能力的研究

香梨优斑螟 Euzophera pyriella Yang是新疆果树重要的蛀果蛀干害虫,严重制约着香梨产业的发展。本研究通过昆虫飞行磨系统测定了香梨优斑螟成虫的飞行能力,结果表明2~5日龄香梨优斑螟飞行能力较强,4日龄飞行能力最强;吊飞14 h,平均飞行距离14.37±1.35 km,平均飞行时间9.40±0.55 h,平均飞行速度1.59± 0.08 km/h 。雄成虫飞行距离显著远于雌成虫,但飞行时间和速度差异不显著。雌雄成虫取食补充营养后飞行能力均有提高,但飞行距离和速度差异不显著。不同交配状态的香梨优斑螟飞行能力测定结果显示,未交配成虫飞行速度和飞行距离均高于已交配成虫,但飞行时间差异不明显。研究结果可为深入阐明香梨优斑螟飞行生物学和扩散机制提供科学依据。     

Codigestion of olive oil mill wastewaters with manure, household waste or sewage sludge

Combined anaerobic digestion of oil mill effluent(OME) together with manure, household waste (HHW) orsewage sludge was investigated. In batch experimentsit was shown that OME could be degraded into biogaswhen codigested with manure. In codigestion with HHWor sewage sludge, OME dilution with water (1:5) wasrequired in order to degrade it. Using continuouslystirred lab-scale reactors it was shown thatcodigestion of OME with manure (50:50 and 75:25 OMEto manure ratios) was successful with a theoreticalOME utilization of 75% and with approx. 87%reduction of the lipids content in OME. An OMEutilization of approx. 55%, and lipid reduction of73% was reached in codigestion with HHW (50:50 and75:25 OME to HHW ratios). The results showed thatthe high buffering capacity contained in manure,together with the content of several essentialnutrients, make it possible to degrade OME withoutprevious dilution, without addition of externalalkalinity and without addition of external nitrogensource.     

Olive mill wastes: Biochemical characterizations and valorization strategies

The olive mill waste generated from olive oil extraction is a major environmental issue, particularly in Mediterranean areas. The extraction of olive oil is achieved through discontinuous or continuous processes. The two processes yield three fractions: a solid residue and two liquid phases (oil and olive mill wastewater). The characterization of these two by-products showed that they are mainly composed of phenolic compounds, carbohydrates, organic acids and mineral nutrients variably distributed depending on the process employed and the agronomic practices. Untreated olive by-products discharged between November and March into the environment are a major ecological issue for olive oil-producing countries due to their high toxic organic loads, low pH, and high chemical and biological demands. In this context, recent research studies highlight on the treatment approaches and valorization options for dealing with olive mill waste residues, predominantly those allowing for the recovery of valuable natural components such as phenolic compounds, dietary fibers, animal feed, biofuel, biogaz, enzymes, polymers and other. The impact of the chemical heterogeneity and water content of olive mill by-products about these processes of valorization and bioconversion is discussed.     

Phytoremediation of palm oil mill secondary effluent (POMSE) by Chrysopogon zizanioides (L.) using artificial neural networks

Artificial neural networks (ANNs) have been widely used to solve the problems because of their reliable, robust, and salient characteristics in capturing the nonlinear relationships between variables in complex systems. In this study, ANN was applied for modeling of Chemical Oxygen Demand (COD) and biodegradable organic matter (BOD) removal from palm oil mill secondary effluent (POMSE) by vetiver system. The independent variable, including POMSE concentration, vetiver slips density, and removal time, has been considered as input parameters to optimize the network, while the removal percentage of COD and BOD were selected as output. To determine the number of hidden layer nodes, the root mean squared error of testing set was minimized, and the topologies of the algorithms were compared by coefficient of determination and absolute average deviation. The comparison indicated that the quick propagation (QP) algorithm had minimum root mean squared error and absolute average deviation, and maximum coefficient of determination. The importance values of the variables was included vetiver slips density with 42.41%, time with 29.8%, and the POMSE concentration with 27.79%, which showed none of them, is negligible. Results show that the ANN has great potential ability in prediction of COD and BOD removal from POMSE with residual standard error (RSE) of less than 0.45%.     

Physicochemical characteristics of microbial content in a modified anaerobic inclining-baffled reactor (MAI-BR) treating recycled paper mill effluent (RPME)

Abstract

Microbial content formed in bioreactors plays a significant role in the anaerobic process. Therefore, the physicochemical characteristics of microbial content in a modified anaerobic inclining-baffled reactor (MAI-BR) treating recycled paper mill effluent (RPME) were investigated using Fourier transform infrared (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG), and derivative thermogravimetric (DTG) analyses, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), Brunauer-Emmett-Teller (BET), and surface area analyzer. FTIR spectra revealed that the microbial content had stronger characteristic peaks corresponding to alcohols, water, lipids carbohydrates, proteins, and mineral compounds. Calcite, muscovite, and lepidolite were the prevalent mineral phases found by XRD analysis. The elemental of these minerals like C, Ca, N, O, and Si was confirmed by XPS results. The microbial content samples from each compartment showed similar thermal behavior. SEM images showed that straight rod-shaped and Methanosaeta-like microorganisms were predominant, whereas C, O, and Ca were noticed by EDS on the surface of granules. The BET surface areas and pores of granules are found to decline throughout the reactor’s compartment, where Compartment 1 had the largest values. Thus, the findings of this study establish further understanding of the physicochemical properties of microbial content formed in MAI-BR during the RPME treatment.     

造纸废水对离体鱼头呼吸运动的影响

本文采用离体鱼头灌注法,以两个造纸厂的制浆造纸废水对147个鲤鱼头进行了人工灌流。结果表明:废水在低浓度(如4%以下)体积稀释液时,鱼头呼吸速率基本未产生影响,而以较高浓度的废水(如5%以上)稀释液灌流与不含废水的鸭绿江水源地水灌流的对照组鱼头比较,几乎均发生了显著性变化,即对鱼鳃盖运动产生了抑制作用,出现了Biot氏呼吸。以往学者们认为,造纸废水主要是由于水中溶解氧(DO)减少而使鱼类致死的,但本工作灌注液中已人工给予足够的DO,提示:有毒物质本身似已直接危及延髓呼吸中枢。 实验同时表明,离体鱼头灌注法可供环境保护部门应用于含多种有机毒性物质的制浆造纸废水的现场监测。     

Direct process integration of cell disruption and fluidised bed adsorption in the recovery of labile microbial enzymes

The practical feasibility and generic applicability of the direct integration of cell disruption by bead milling with the capture of intracellular products by fluidised bed adsorption has been demonstrated. Pilot-scale purification of the enzyme L-asparaginase from unclarified Erwinia chrysanthemi disruptates exploiting this novel approach yielded an interim product which rivalled or bettered that produced by the current commercial process employing discrete operations of alkaline lysis, centrifugal clarification and batch adsorption. In addition to improved yield and quality of product, the process time during primary stages of purification was greatly diminished. Two cation exchange adsorbents, CM HyperD LS (Biosepra/Life Technologies) and SP UpFront (custom made SP form of a prototype stainless steel/agarose matrix, UpFront Chromatography) were physically and biochemically evaluated for such direct product sequestration. Differences in performance with regard to product capacity and adsorption/desorption kinetics were demonstrated and are discussed with respect to the design of adsorbents for specific applications. In any purification of L-asparaginase (pI = 8.6), product-debris interactions commonly diminish the recovery of available product. It was demonstrated herein, that immediate disruptate exposure to a fluidised bed adsorbent promoted concomitant reduction of product in the liquid phase, which clearly counter-acted the product-debris interactions to the benefit of product yield.     

棉铃虫的飞翔活动

实验研究表明,棉铃虫初羽化个体极少活动,１日龄以后活动趋于频繁。个体日活动以２０：００￣２１：００和３：００￣５：００为２个高峰期,１￣３日龄主要以交配和觅食为主,４日龄以后多表现产卵活动。３￣６日龄成虫的飞翔能力最强,连续吊飞第６日龄个体,其平均累计飞行时间达４１．３０ｈ,平均飞行距离２３９．７ｋｍ,个体最远飞行距离３１１．２９ｋｍ,最长飞行时间５９．６８ｈ,最大飞行速度３．２１ｍ／ｓ。棉铃虫在