bluuebunny/crossref_metadata_2025 huggingface dataset:
Attached Growth Reactor for Bod Removal and Nitrification with Polyurethane Foam Medium
Authors: Tsuno H. , Somiya I. , Matsumoto N. , Sasai S.
Published: May 2018

Ammonium nitrogen is a principal material of concern in treated water discharge. Applicability of completely mixed series reactor with Polyurethane foam cubes as attached medium to municipal sewage treatment for BOD removal and nitrification was experimentally examined. Nitrifier grew preferably on the polyurethane foam cubes, and its nitrifying activity reached 0.33 (mg N/hr·cube) for the cubes of 8 cm . BOD removal was completed in 4 hours, and then nitrification began to occur and was completedin 10hours under the condition of temperature as low as 15 degrees centigrade. The heterotrophic bacteria and nitrifier grew separately in the different cells of the reactor. Nitrification activity was inhibited by some organics included in the influent. The effect of inhibition was severer with increasing DOC.
Removal of Phenols with Tyrosinase Immobilized on Magnetite
Authors: Wada S. , Ichikawa H. , Tatsumi K.
Published: May 2018

Tyrosinase was immobilized on magnetite using amino groups from an enzyme for the purpose of finding means for removing phenols from wastewater. This immobilization noticeably improved storage and operational stabilities, due possibly to elimination of reactions of amino groups in tyrosinase with quinones formed by oxidation of phenols. The oxidation of substituted phenols with magnetite-immobilized tyrosinase was dependent on substituent groups and their positions. P− ASubstituted phenols were better substrates than o− and m− substituted phenols.
Degradation Rate of Aircraft Deicing Fluid in a Sequential Biological Reactor
Authors: Sabeh Y. , Narasiah K. S.
Published: May 2018

Glycol-based fluids are used at northern airports during the winter to deice aircraft prior to takeoff. As a result of these operations, an appreciable amount of deicing fluid mixes with runoff and finds its way into nearby streams and lakes. The research described herein focuses on establishing the reaction rate coefficient (k) for the biological degradation of UCAR ADF-D in a sequential biological reactor under different conditions of temperature and organic bad. The rate of removal of the deicing chemical follows a first-order model. It was found that, at 22°C with a food-to-micrcorganisms ratio (F/M) of less than or equal to 2.8, a fourfold increase in F/M reduces k values by a factor of eight. The organic load is less sensitive when F/M is equal to or greater than 2.8: a seven-fold increase in F/M decreases k by only a fector of three. Temperature is very important since, when F/M ≈ 2, Jc returned values of 1.03, 0.29, and 0.05, respectively, for temperatures of 22°C, 10°C, and 4°C. This study clearly demonstrates that UCAR ADF-D can be treated biologically and that the rate of removal can be significantly affected by organic load and temperature.
Degradation of Carbaryl and 1-Naphthol by Spent Mushroom Compost Microorganisms
Authors: Regan R. W. , Kuo W. S.
Published: May 2018

The capabilities of spent mushroom compost microorganisms in degrading carbaryl and 1-naphthol were evaluated. No lag phases were observed for the two compounds. The microbial degradation kinetics of the two compounds could be interpreted very well by Pseudo-first-order model. The biodegradation rate constants of two compounds were affected by initial biomass concentration and aeration rate significantly. The rate constants of carbaryl and 1-naphthol were 0.2S1 hr−1, 0.105 hr−1 respectively under the aerobic condition (aeration rate 600 ml/min and initial biomass concentration 100 mg/l). Thus, the half-life of carbaryl and 1-naphthol were 2.761 hrs, 6.600 hrs respectively.
Biodegradation of Wool Scouring Effluent on a Laboratory Scale
Authors: Oellermann R. A. , Ronen T. , Meyer V.
Published: May 2018

A continuously fed, sequential anaerobic-aerobic-aerobic reactor system was used to treat wool scouring effluent. The chemical oxygen demand (COD) in the anaerobic reactor was reduced from 30500 mg/ℓ to 3000-5000 mg/ℓ. In the first aerobic reactor this was further reduced to 1200-1800 mg COD/l. The final discharge from the second aerobic reactor had a COD of 500-1000 mg/ℓ at a hydraulic retention time of 2-3 d. Nitrification was erratic but sufficient to reduce the ammonia-N to levels of 20 mg/ℓ and less. Mixed liquor suspended solids and volatile suspended solids could be maintained at sufficiently high levels in completely mixed systems and efficient biomass retention in the aerobic rotating biological contactor resulted in an overall removal of 98.4% COD.
Sludge Utilization and Reduction Experiences in the Pulp and Paper Industry
Authors: Öztürk I. , Eroglu V. , Bastürk A.
Published: May 2018

This paper presents pilot-scale experiences on utilization of primary sludges from an integrated pulp and paper mill in the manufacturing of hardboard. The results have shown that the primary sludge added in 1/4 ratio yields the best result considering quality and operating aspects for the hardboard production. Lab-scale anaerobic treatability studies were carried out by an upflow anaerobic sludge blanket reactor (UASBR) with a volume of 10.351 using settled effluents from the related industry as the feed. Anaerobic treatability study results have shown that such an application prior to existing activated sludge system may provide 70 percent reduction in energy requirement for aeration and about 65 percent net reduction in excess biological sludge production.
Accumulation of Zinc in Activated Sludge
Authors: Moriyama K. , Kobayashi Y. , Mori T. , Nakahara H. , Chino M.
Published: May 2018

The highest zinc concentration in activated sludge occurred at 15 days SRT in a laboratory simulation of the batch activated sludge process. It is possible to maintain a low concentration of zinc in composted sewage sludge, which is derived from excess activated sludge, by keeping the SRT short.
Effect of the Surface Characteristics of Seed on Copper Precipitation
Authors: Wang Y. , Anderson P. R.
Published: May 2018

Two types of seed with different surface area are used in a precipitation system to evaluate the effectiveness of seed surface characteristics on sludge dewatering properties. We expect that the surface area of the seed will stongly affect the sludge properties. The preliminary study shows that the seeded system has a lower precipitation pH and lower supersaturation level.
Metals Removal and Recovery by Arthrobacter sp. Biomass
Authors: Grappelli A. , Campanella L. , Cardarelli E. , Mazzei F. , Cordatore M. , Pietrosanti W.
Published: May 2018

Experiments on the real possibility of employing microorganisms to capture inorganic polluting substances, mainly heavy metals from urban and industrial wastes, are running using bacteria biomass. Many strains of Arthrobacter spp., gram-negative bacteria, diffused in the soil also inacondition of environmental stresses, have been proved to be particulary effective in heavy metal capture (Cd, Cr, Pb, Cu, Zn). The active and passive processes in accumulation of metals by bacteria were studied. Our experiments have been done on fluid biomass and on a membrane both for practical use and for an easy recovery.
Degradation of Cyanobacteria, Microcystis by Microflagellate, Monas guttula
Authors: Sugiura N. , Inamori Y. , Ouchiyama T. , Sudo R.
Published: May 2018

Characteristics of degradation of cyanobacteria, Microcystis aeruginosa, by Masugophota-Monas guttula were examined. Monoxenic M.guttula was isolated from sewage in the biological oxidation facility equipped in Kasumigaura Water Works. M.guttula was able to efficiently degrade viable cells of M.aeruginosain a short time. The removal of cells by M.guttula was 90% at 48 hr cultivation. The specific growth rate (µ) and generation time (tg) of M.guftuia were 4. l day−1 and 4.0 hr, respectively. The maximum specific growth rate(µmax) and saturation coefficient (Ks) of the microbe were 4.4day−1 and 2.4 mg/l with Lineweaver-Burke equation. Effects of physical factors on the removal of M.aeruginosa by M.guttula, pH and temperature were examined. Greater than 80% of removal was obtained at pH 7.0. At 30°C, the maximum removal was over 90% as compared with 20% at 5°C. It was clarified that M.guttula could effectively utilize M.aeruginosa as food, and it was found that pH and temperature were important physical factors to remove the Cyanobacterium M. aeruginosaby microflagellate M.guttula.
Investigation of Bacterial Populations Producing Elevated MPN Values and False Positive Fecal Coliform Counts and Applicable Disinfectants in an Industrial Wastewater
Authors: Davis E. M. , Manville D. L. , Mathewson J. J. , Meriwether G. W.
Published: May 2018

This poster presents data on the types of bacteria which produced elevated, most probable number (MPN) fecal coliform values in an industrial waste treatment plant effluent. The principal influent stream, a pulp and paper mill wastewater, contained principally Klebsiella species of environmental, not enteric origin. Fecal streptococci and enterococci were low in numbers. Eight disinfectants were tested on a small (currently acid disinfected) municipal wastewater incoming stream and on the main plant effluent.
Polyphosphate and Poly-β-Hydroxybutyrate Production in Acinetobacter spp. Isolated from Activated Sludge
Authors: Rees G. N. , Vasiliadis G. , May J. W. , Bayly R. C.
Published: May 2018

Three strains of Acinetobacter isolated from activated sludge were examined for their capacities to produce polyphosphate and poly-β-hydroxybutyrate following growth under phosphate, ammonia and sulfate limitation. When growing on complete medium levels of polyphosphate produced by RA3117 were about six times higher than in RA3757 and levels were unchanged when growing on ammonia or sulfate limitation. Strain RA3197 produced polyphosphate only when subjected to sulfate limitation. No strain produced polyphosphate when growing under phosphate limitation. When the three strains were grown in normal medium at 100% oxygen saturation, no strain produced poly-β-hydroxybutyrate. When subjected to phosphate, ammonia or sulfate limitation RA37S7 produced up to 10% PHB as dry weight. Strains RA3117 and RA3197 produced moderate amounts of sudanophilic material only when grown under phosphate limitation, however, only trace levels of PHB were detected. In RA3757 levels of the poly-β-hydroxybutyrate synthesizing enzymes - β-ketothiolase and acetoacetyl-CoA reductase - correlated well with poly-β-hydroxybutyrate production but in strains RA3117 and RA3197 no activity of either of the enzymes was observed.
Biological Nutrient Removal at the Blue Plains Wastewater Treatment Plant in Washington, D.C.
Authors: Kang S. J. , Bailey W. F. , Jenkins D.
Published: May 2018

A pilot study was conducted to establish feasibility of biological nutrient removal at one of the most advanced wastewater treatments in the U.S. The results of the study revealed technical feasibility of biological phosphorus removal at extremely high F/M (0.84 1/day) and a short hydraulic detention time (2.2 hours) in the first stage activated sludge system. Due to phosphorus limitation of 0.18 mg/l, it was determined that none of the single sludge BNR processes was applicable at this facility. In the second stage, therefore, biological nitrogen removal was achieved with both methanol and primary effluent as a carbon source. Another significant finding was that after acclimation, the primary effluent exhibited the same rate of denitrification as with methanol (2.7 mg NO3− N/gVSS·hr). Further pilot testing revealed correlations among such process variables as detention time, BOD to nitrogen ratio, and effluent nitrogen concentration.
Critical Design and Process Control Features to Optimize Biological Nutrient Removal in Temperate Climates
Authors: Sen D. , Randall C. W. , Copithorn R. R. , Grizzard T. J.
Published: May 2018

Biological nutrient removal (BNR) is being selected as the cost effective option for enhancing nutrient removal at plants located in temperate climates in the Chesapeake Bay Watershed and the Long Island Sound in the U.S.A. However, there is considerable discrepancy in the reported values for temperature sensitivity for nitrification and denitrification rates in winter, as observed at different plants and those reported in higher strength wastewaters in Europe and South Africa. Full scale data show that the temperature sensitivity for nitrification is considerably lower. Denitrification rates in the primary anoxic zone are also lower, possibly because of lower influent strengths (250 to 450 mg/L COD).

Secondary clarifier limitations have been a key cost factor in attempting year round nitrogen removal as against seasonal (summer) nitrogen removal. The anoxic MCRT and anoxic volume requirements have been a critical cost factor in designs. Split flow designs, where a fraction of the influent flow is sent directly to the anoxic zone, have allowed process designs with lower anaerobic volumes. The readily available COD in the fraction of the influent which enters the primary anoxic zone enhances denitrification rates. Though the anaerobic cell receives less than 100 percent of the influent flow, excellent biological phosphorus removal can still be maintained with phosphate detergent ban wastewaters. The fraction of biomass maintained under anaerobic conditions (and the anaerobic volume) can be reduced because the phosphate detergent ban has decreased the amount of phosphorus which has to be removed for the same influent COD. Biofilm and suspended growth systems have been combined in a single reactor to reduce volume requirements for nitrogen removal.
Pilot Evaluation of Ceramic Membranes in Surface Water Treatment with Coagulant Pretreatment
Authors: Veerapaneni S. , Brejchova D. , Schmelling D. C. , Nazzal F. F. , Wiesner M. R.
Published: May 2018

Results from a pilot scale study on the performance of ceramic membranes in treating high turbid waters are presented. Coagulation pretreatment using alum or ferric sulfate was found to improve permeate quality and increase permeate flux. In comparison with ferric sulfate, pretreatment with alum resulted in lower permeate turbidity. DOC removals between 45-65% are possible with coagulation. Ferric sulfate was more effective in reducing organic carbon concentrations. The highest permeate fluxes were observed with alum coagulation, at pH 6. The quality of the membrane permeate was similar to that achievable by packed bed filtration. Careful control of coagulant dose and pH is required to optimize performance of the process and may pose difficulties in full scale operation.
Contamination of Alluvial Aquifers by Metal Industries in Parts of Central Ganga Basin, India
Authors: Ali A.
Published: May 2018

Physicochemical characteristics of wastewater from metal industries in parts of central Ganga basin, district Aligarh, India and the differential accumulation of heavy metals in shallow aquifers were investigated. It has been observed through analytical results that the concentration of heavy metals like Fe, Cu, Mn, Cd and Pb are higher than the suggested guidelines of World Heath Organisation, 1985 both in wastewater and shallow groundwater. Since groundwater is the only source of water supply for drinking, agricultural and industrial requirements, it is an essential pre-requisite that the existing groundwater resource should be protected from further degradation by providing some suitable measures like treatment of the wastewater before letting them to the drainage system.
Trace Metal Soil Quality Criteria to Protect Ground Water
Authors: Lee J. , Chen B. , Allen H. E. , Huang C. P. , Sparks D. L. , Sanders P.
Published: May 2018

A major problem in site remediation is frequently the lack of appropriate standards for pollutants in soil. Lack of standards for an exposure route can result in subjective judgments regarding the extent of remediation needed. These problems are particularly important when considering the potential for groundwater contamination by inorganic materials. The partitioning of trace metals is highly dependent on the nature of the soil and on the solution pH. The maximum level of metal in soil for which the equilibrium soluble metal does not exceed the drinking water standard can be computed, at any pH, from the measured partition coefficient for any metal and soil.

The sorption of cadmium and lead onto major types of New Jersey soil has been determined as a function of pH. As the pH decreased, the amount of adsorbed metal decreased.

As is conventionally done, we have transformed these data into sorption coefficients (Kd) which are a function of pH. To apply such data in the decision making process, it is necessary to use the Kd and appropriate conditions of soil/groundwater in the environment. The calculation determines the maximum concentration of metal which will not result in exceedence of water quality standards. Thesecriteria can be used as a soil standard which will be protective of groundwater quality.

We developed adsorption/desorption relationships in the form of a mathematical model and computed the maximum level of metal in soil for which the equilibrium soluble metal will not exceed the drinking water standards.
Spherical Diffusion Model of Interspecies Hydrogen Transfer in Steady-State Methanogenic Reactors
Authors: Smith D. P.
Published: May 2018

A previously developed spherical diffusion model of interspecies molecular hydrogen transfer was applied to a mathematical model of ethanol and propionate methanogenesis in a dispersed-growth, continuously stirred tank reactor (CSTR). Steady-state methanogenesis at a 0.10 day−1 space velocity required a hydrogen concentration difference of 1.12 × 10−5 aim (8.4 × 10−12 moles/cm3) between the surface of the propionate organisms and the bulk solution. The total difference in hydrogen concentration between source organism and sink organism Ihydrogenotrophic methanogenstwas 2.1 × 10−5 atm (1.6 × 10−11 moles/cm3). Steep gradients in hydrogen concentration existed only at close proximity to the bacterial spheres, with hydrogen concentration approaching bulk solution concentration at distances greater than 10 microns. Small hydrogen gradients and the bulk solution concentration prevailed through the majority of the reactor aqueous volume. Overall, the incorporation of hydrogen mass transfer resistance into the mathematical model had only a slight effect on hydrogen partial pressure, organic substrate levels, and bacterial mass concentrations predicted by the steady-state solution.
Computer-Aided Design for Stabilization Ponds
Authors: Li X.-W.
Published: May 2018

It is urgently necessary to develop practical programs for different purposes in the field of wastewater treatment. Now the design programs for grit chambers, anaerobic ponds, facultative ponds, aerobic ponds, aerated ponds and polishing ponds are being developed. Programs for automated plotting and man-machine interactive plotting are needed too. By using AutoCAD (Version 9.03 or 10.0), a secondary development of the softwares for engineering drawing of stabilization pond has been developed, which possesses the function of writing out explanatory notes. A program for writing out explanatory notes in Chinese is also being developed. In the process of developing such softwares, high-level language AutoLISP is used, so that the softwares possess artificial intelligence. Up to now the graphic softwares for plotting the general plan drawings and elevation drawings of grit chamber, various ponds, and pond systems have been developed.
Uasb Treatment of Monosodium Glutamate Wastewater; Dynamic and Kinetic Behaviour of the Start-Up of the Reactor
Authors: Cao Y.-S. , Zhang H. , Li Y.-Z.
Published: May 2018

Simple reactors were used to carry out the feasibility study of the anaerobic treatment of monosodium glutamate (MSG) waste water by granular sludge and the determination of Monod kinetic constants. Aerobic flocculent sludge was compared with the granular sludge. It took one month for a UASB reactor seeded with granular sludge to increase the space loading rate of MSG wastewater from 1. 87 kgCOD/m3. day to 18. 9 kgCOD/m3. day. The maximum influent concentration of COD ranged between 4500 to 5000 mg/L, and the removal efficiency was around 80%. Gas production and process stability was satisfied. Preliminary design parameters and some recommendations were given. Sludge bed expanding and wash–out during start–up process were observed and discussed. The application of the kinetic constants obtained from the feasibility study to the UASB start–up process indicated that the activity of the granular sludge increased substantially; they could not be used to describe the UASB process.
Anionic Surfactants Removal and Biodegradation in a Large Treatment Plant
Authors: Romano P. , Ranzani M.
Published: May 2018

A full scale study was conducted to investigate the destination of LAS (Linear Alkylbenzene Sulfonate) in Italy's greatest WWTP (Waste Water Treatment Plant): the Turin central plant. Specific LAS data, using established HPLC techniques, have been obtained in the influent and effluent streams, in the dissolved phase (waters) and in the adsorbed one (suspended solids and sludges) to reach a complete mass balance. LAS removal higher than 99% and LAS biodegradation ca. 85% have been observed. Attention has been also given to LAS intermediates of biodegradation, namely the sulfo fenil carboxylaters (SPC) resorting to HPLC and GC-MS techniques, the latter after derivatization. On the basis of SPC data it is possible to measure esperimentally also the biodegradation in sewers before the WWTP (at least 12%) and the mineralization degree of LAS in the WWTP (ca. 80% vs. total biodegraded LAS). The impact of the WWTP on the LAS concentration of the Po river waters has been also considered.
Appropriate Sanitation Options for Southern Africa
Authors: Marks R. F.
Published: May 2018

An overview is given of the present types of sanitation systems used in both rural and urban areas in Southern Africa, with particular reference to Zimbabwe. On-site and off-site dry sanitation methods are described, including different types of pit latrines, with special reference to the Ventilated Improved Pit (VIP) Latrine. Wet systems with on or off-site disposal methods are briefly described, and details are given of two methods of off-site disposal which are widely used in Zimbabwe, viz Waste Stabilisation Ponds (WSP) and the Modified Activated Sludge (MAS) system for biological nutrient removal. The difficulties of implementing low-cost and incremental sanitation systems are mentioned, and suggestions are made of ways to overcome these difficulties.
Criteria for Assessing Appropriate Technology for Sewage Treatment and Disposal
Authors: Boshier J. A.
Published: May 2018

This Conference is concerned with appropriate technologies for waste management. How a judgement is made as to what is appropriate for each country, region and local community is of importance. A solution for one community will not necessarily be applicable to another. The Parliamentary Commissioner for the Environment's Office in New Zealand has a role of evaluating the performance of public authorities in their environmental management responsibilities. The Commissioner has reviewed the performance of a range of public authorities in New Zealand in respect to sewage treatment and disposal. These include the regional council responsible for the majority of sewage infrastructure in the Auckland urban area, a local authority responsible for two adjacent coastal communities and a local authority responsible for an off-shore island. The choice of technology for each situation has been influenced by the concerns of the indigenous peoples, the aspirations of the communities and the choices available for disposal of the treated effluent
Predicting the Dewatering Performance of Belt Filter Presses
Authors: Novak John , Knocke William , Burgos William , Schuler Paul
Published: May 2018

Two sewage sludges were used to compare full-scale belt press performance to two types of laboratory devices to determine if either could be used to predict the performance. The wedge zone simulator (WZS) could accurately predict polymer demand, filtrate quality and cake solids. The shear tester used with a CST device was no better (ban a free drainage test at predicting polymer requirements.
Fundamentals of Sludge Dewatering in Freezing Beds
Authors: James Martel C.
Published: May 2018

After several years of research, the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) has developed a new unit operation for sludge dewatering called a freezing bed. The freezing bed uses natural freeze-thaw to dewater sludge. Essentially, it is the cold regions counterpart to the drying bed. Pilot and full-scale studies conducted in the United States have demonstrated that freezing beds can dewater both water and wastewater treatment sludges to greater than 20% total solids content. The best results were obtained with alum sludge, which was dewatered to 82% solids. The design of freezing beds will depend on the depth of sludge that can be frozen and thawed at the proposed site. Mathematical models capable of calculating the design depth are presented.
Improved Sludge Dewatering by Dual Polymer Conditioning
Authors: Senthilnathan P. R. , Sigler Roger G.
Published: May 2018

Dual polymer conditioning enhanced the dewatering characteristics of aerobically digested activated sludge from a pharmaceutical industry. The solids content of the dewatered sludge cake, from a belt filter, increased from 8-11% range to 11-14% range due to dual polymer conditioning. In addition, dual polymer conditioning improved the compressibility of the sludge cake, reduced blinding of the belt filter media, and enhanced solids capture by the belt filter. Initially, bench scale studies were conducted to screen suitable polymers for conditioning. From these studies, two polymers, namely, Calgon Catfloc 8964 (a low molecular weight, high cationic charge) and Calgon WT2476I (a high molecular weight, high cationic charge) were chosen for full scale experiments. This paper reports the details of the polymer screening methods, dual polymer conditioning procedures, and the results of the full scale trials.
Fate of Biological and Chemical Contaminants from On-Site Disposal of Liquid Piggery Wastes: Results from a Soil Column Study
Authors: Lam K. C. , Ng S. L. , Neller R. J.
Published: May 2018

To assess the feasibility of the soakaway system in treating piggery wastes, eight columns of 3 m length were packed with five commonly occurring soils from Hong Kong and were dosed with pig slurry daily for a period of four months. Infiltration rates of the columns were monitored daily while slurry and soil solution were sampled weekly or fortnightly and analyzed for the major bacterial, organic and inorganic contaminants. Purification efficiency was higher in the volcanic soils than in the coarser granitic soils. Most of the contaminants were removed in the top 1 m unsaturated zone of the columns. Analysis of the effluent collected at the end of the 3 m columns packed with granitic and volcanic alluvial soils indicated purification efficiencies of 100% for E. coli and more than 95% for BOD5, total-P, total-N, PO4, NH4-N and NO3-N. The purification efficiencies of footslope deposits and in-situ weathered materials were significantly lower.
Investigating Land Based Disposal of Bolivar Reclaimed Water, South Australia
Authors: Schrale G. , Boardman R. , Blaskett M. J.
Published: May 2018

The Bolivar Sewage Treatment Works (STW) processes the urban and industrial sewage from the northern and eastern suburbs of Adelaide. The treatment capacity is equivalent to the sewage production of 1.1 million people. The disposal of more than 40 000 ML of reclaimed water into the sea has caused a progressive degradation of about 950 ha of seagrass beds which threatens the sustainability of the fisheries and marine ecosystems of Gulf St. Vincent. The current practice will no longer be viable to achieve compliance with the SA Marine Environment Protection Act, 1990.

A Inter-Departmental Working Party recommmended that the Bolivar reclaimed water be disposed by irrigation of suitable land on the coastal plains north of Adelaide. They proposed the construction of two pipelines: a 12 km long pipeline to extend the distribution of reclaimed water in the most intense portion of the 3 500 hectares of irrigated horticulture on the Northern Adelaide Plains, and a second, 18 km long pipeline to deliver the remainder to a more northerly site for irrigation of an estimated 4 000 hectares of hardwood plantations.

The paper summarizes the findings as they relate to public health, environmental, technical and financial aspects of land based disposal. Land based disposal would completely eliminate the marine degradation and also arrest the over-use of the NAP underground water resources for horticulture. The total net costs over thirty years for land based disposal are about $ 21.8 million. The ‘horticultural' pipeline of the land based disposal scheme is expected to be commercially viable. A shortfall in revenue from the afforestation component is expected and may need to be considered as an environmental cost of ceasing marine disposal.
Development of an On-Site Moderate Land Limited Small Farm Wastewater Treatment Plant
Authors: Yang P. Y. , Chen H. , Kongricharoern N. , Polprasert C.
Published: May 2018

Two types of pilot scale systems, namely, reactors in series and single reactor, were tested for developing an on-site small wastewater treatment plant. Combined bio-fixed film and aquatic plant for a moderate land limited and tropical application were tested for the proposed system. Anaerobically digested wastewater with TCOD concentration of about 500 and 1000 mg/L was used as the substrate and various hydraulic retentiontimes(HRT) and loading rates were tested for optimal removal of organic and inorganic pollutant contained in the anaerobically digested wastewater. It was found that the removal efficiencies of TCOD and NH4-N of more than 90% and 95%, respectively, could be achieved under the loading rate of 120 g TCOD/m3/day and 13 g NH4-N/m3/day and HRT of more than 14 days. The system has demonstrated that it is simple in construction and operation. It is highly possible to be integrated as one of the components of the swine waste management system in the tropics and moderate land limited conditions.
Application of Bacterial Product for Zero-Liquid-Discharge Pig Waste Management under Tropical Conditions
Authors: Ong H. K. , Choo P. Y. , Soo S. P.
Published: May 2018

The traditional method of waste disposal employed by pig producers in Malaysia is washing wastes down with plenty of water. While this method cleans the pig pens and cools down the animals, it generates a lot of wastewaters which pollute the waterways and causes social problems. An experiment was conducted to study the effect of in situ solid waste handling within the pig pens in order to avoid wastewater generation. This was carried out by in situ aerobic digestion of waste in a litter of sawdust to which was added a bioproduct. Ninety pigs of about 21 kg initial weight were allotted to three treatment groups, namely: 1, Control Group where pigs were kept on concrete floor, washed once daily and fed a standard diet; 2, pigs kept without washing on litter floor containing bioproduct; 3, pigs kept on litter floor and fed with a standard diet containing 1% of the bioproduct. The bioproduct was applied on litter at 120 g/m2 initially and then subsequently at 100 g/m2 every fortnight. When litter was appropriately managed by periodic mixing and moisture adjustment, odour score was significantly reduced in litter floor compared with concrete floor. Similarly, incidence of fly infestation was significantly reduced in litter floor. However, animal performance in terms of average daily body weight gain and efficiency of feed conversion was significantly reduced in pigs kept on litter floor compared with those on concrete floor. Pigs kept on litter for 90 days had increased leaf fat, but did not exhibit any significant differences in other carcass characterisitics compared with those kept the traditional way.
Extreme Solid Compressibility in Biological Sludge Dewatering
Authors: Sørensen Peter B. , Aage Hansen Jens
Published: May 2018

The degree of compressibility in the filter cake structure associated with mechanical dewatering of a polyelectrolyte conditioned biological sludge is investigated. Filtration/expression tests are carried out using both an A1(OH)3 and a biological sludge. A numerical model for filtration/expression is established and used to simulate liquid pressure development A comparison between measurements and calculations shows that the compressibility of the biological sludge is extremely high. Using filtration theories, the degree of compressibility is shown to be so high that a thin skin which accounts for nearly all the hydraulic pressure drop across the filter cake is likely to be formed just above the medium. This extreme compressibility behaviour suggests a reconsideration of the usual power law description of the relations between solid contact pressure, porosity and specific flow resistance. An equation showing the effect of the compressibility on the relation between filtrate flow and applied pressure during filtration is derived, and it is concluded that for extremely compressible solids, the filtrate flow becomes independent of the pressure applied.
Application of the Streaming Current Detector in Sludge Conditioner Selection and Control
Authors: Dentel S. K. , Abu-Orf M. M.
Published: May 2018

The streaming current detector (SCD) can be utilized to measure charge characteristics of a suspension or sludge which can be related to zeta potential. In this study, the SCD was used as a tool for polymer selection and dose control toward improved sludge conditioning prior to centrifugation.

In laboratory studies, polymer addition to sludges was followed by controlled mixing then measurement of streaming current (SC) and capillary suction time (CST). Plant studies employed facilities at an 18.8 MGD wastewater treatment facility in Warminster, PA, USA. Anaerobically digested sludge was conditioned with varying doses of cationic polymer and dewatered using two parallel solid-bowl centrifuges.

The polymer caused a transition from negative to positive charge in both conditioned sludge and centrate. The polymer dose range for optimum dewaterability, as indicated by CST and solids recovery, corresponded to near-zero SC in all cases. Even when greater mixing intensities or times increased the polymer demand, the charge transition was similarly related. This correspondence was used to successfully confirm a calculation method establishing velocity gradient and mixing time similitude between jar tests and in-line mixing prior to the centrifuge.
Adsorption of Toxic Shocks on Carriers in Anaerobic Biofilm Fluidized Bed Reactors
Authors: Mol N. , Kut O. M. , Dunn I. J.
Published: May 2018

The influence of different carrier materials on the performance of single stage anaerobic biofilm fluidized bed reactors by toxic shock loadings was studied in parallel experiments. The carrier materials investigated were porous glass (Siran), quartz sand, pumice, shale, activated carbon and anthracite. Since the composition and morphology of the biofilm is influenced by the individual wastewater, vapor condensate from a sulfite cellulose process and mixed brewery wastewaters were used as substrates. The phenol adsorption characteristics were measured on bare and biofilm-coated carriers. Biofilm-coated carriers adsorbed larger amounts of phenol than bare carriers. It was observed that the biofilm morphology and the corresponding adsorption capacity of biofilm carriers depended on the individual wastewater characteristics. It was also shown that activated carbon (and partly anthracite) adsorbed large amounts of phenol, mostly irreversibly. The performance of the individual reactors was studied under short-term dynamic phenol shocks (constant hydraulic retention time (HRT) 10 h, loading rate increase from 12 to 20 kg COD/m3d during the shock period of ca.10 h). During the toxic loading in continuous operation, an increase of phenol concentration was observed in the effluent, coupled with an up to 20% decrease in the gas production rates. During this period, acetic acid accumulation was also observed, indicating the inhibition of methane formation. Following the shock, all reactors showed a relatively rapid recovery to the original activity after 2-3 hydraulic retention times.
Survival of Plant Pathogens and Weed Seeds during Anaerobic Digestion
Authors: Engeli H. , Edelmann W. , Fuchs J. , Rottermann K.
Published: May 2018

The survival of Plasmodiophora brassicae was studied at digestion temperatures of 35 °C and 55 °C in laboratory batch digesters within one and two weeks, respectively. The study showed that digestion at 55 °C almost completely reduced the ability of infecting bait plants.

The seeds of Rumex obtusifolius and Lycopersicon lycopersicum (tomatoes) were completely destroyed at 55 °C and a digestion time of 14 days, in laboratory batch digesters.

The experiments carried out in a two stage pilot plant (Leach-Bed Solid Phase batch Digester for hydrolysis and a pulsating dynamic anaerobic filter for methanogenesis) showed that hydrolytic conditions are mainly responsible for the killing of weed seeds. Some additional data on the qualities of different digested substrates are presented.
A 5 pH Point Titration Method for Determining the Carbonate and SCFA Weak Acid/Bases in Anaerobic Systems
Authors: Moosbrugger R. E. , Wentzel M. C. , Ekama G. A. , Marais G. v. R.
Published: May 2018

A 5 pH point acid titration method is proposed to measure the short chain fatty acids, total carbonate species concentration and H2CO3*alkalinity in anaerobic systems. To test the method, aqueous solutions containing NaHCO3 (1990; 2488 mg/ℓ as CaCO3) and the short chain fatty acid (SCFA) acetic acid with concentrations ranging from 100 to 1000 mg/ℓ were titrated using the method; the H2CO3*alkalinity and SCFA estimates ranged around the expected values with an average standard deviation of 5 and 8 percent respectively. Estimates of the SCFA by the method and by Montgomery et al 's wet chemical method on the effluents of UASB reactors treating brewery and wine distillery waste correlated closely (r = 0.98). Other tests demonstrated as predicted that the presence of ammonium has a negligible effect on the derived results. However, phosphates can have a significant effect on the H2CO3*alkalinity but not on the SCFA estimates. The phosphate effect is eliminated in the derived estimates if its concentration is known. The method also identifies errors in pH due to the residual liquid junction effect or poor calibration and corrects the estimates accordingly; deliberately imposed pH calibration errors were identified and their error effects on the H2CO3*alkalinity and SCFA estimates largely corrected.
Pellet Formation of Fungi and Its Application to Starch Wastewater Treatment
Authors: Fujita M. , Iwahori K. , Yamakawa K.
Published: May 2018

The pellets formed by Aspergillus niger increased in number and their average diameter became smaller with the increase in the speed of revolution, i.e. the G value, and the number of pellets bad linear relationship with the logarithm of the G value within the range of about 100-300 sec−1. The form and high intensity of pellets were maintained under aeration, but their diameter became gradually larger during the continuous experiments of starch wastewater treatment The pellets formed by A. niger bad good ability of starch decomposition and TOC removal, because over 90% of the starch was decomposed and about 75% of the TOC was removed during the treatment. Therefore, it was suggested from the practical point of view that the pellet formation by A. niger could be controlled by the shearing stress and that these pellets were effective for the starch wastewater treatment
Treatment of Cercla (Comprehensive Environmental Response, Compensation, and Liability Act) Leachates by Carbon-Assisted Anaerobic Fluidized Beds
Authors: Suidan M. T. , Schroeder A. T. , Nath R. , Krishnan E. R. , Brenner R. C.
Published: May 2018

Two anaerobic granular activated carbon (GAC) expanded-bed bioreactors were tested as pretreatment units for the decontamination of hazardous leachates containing volatile and semivolatile synthetic organic chemicals (SOCs). The different characteristics of the two leachate feed streams resulted in one reactor operating in a sulfate-reducing mode and the second in a strictly methanogenic environment. Both reactors were operated with a 6-hr unexpanded empty-bed contact time and achieved SOC removal acceptable for pretreatment units. In both reactors, the majority of the SOCs were removed by biological activity, with GAC adsorption providing stability to each system by buffering against load fluctuations.
Importance of Epilwimnion Phosphorus Loading and Wind-Induced Flow for Phytoplankton Growth in Ěímov Reservoir
Authors: Hejzlar J. , Balejová M. , Kafková D. , Růžička M.
Published: May 2018

Total reservoir phosphorus loading and epilimnion phosphorus loading were estimated and their relations to phytoplankton quantity examined for spring-summer periods during 1984-1991 in Ěímov Reservoir, a stratified, moderately eutrophic reservoir with variable surface and deep outlets operation. Epilimnion phosphorus loading was quantified from the volumes of water entering the epilimnion due to the inflow temperature-density currents and due to the surface discharges that were determined by the one-dimensional dynamical simulation model of reservoir hydrodynamics DYRESM 5. The fraction of total phosphorus input into the reservoir entering the epilimnion varied between 12 and 31% in different years. Chlorophyll a concentration measured near the dam correlated only with the epilimnion phosphorus loading due to surface discharges. The phosphorus input by river water entering directly the epilimnion caused an increase of the chlorophyll a concentration at the dam only occasionally if the wind was of sufficient velocity and favourable direction to induce mixing and transport of epilimnion water masses from the headwater part of the reservoir to the dam.
A Theoretical Consideration of the Kinetics of Multiple Substrate Utilization in Anaerobic Digestion
Authors: Kuroda M. , Sakakibara Y. , Jin Wang , Erjie Yu , Baozhen Wang , Quanda Yang
Published: May 2018

Degradation of a mixture of various organic substances was regarded as a multiple substrate phenomenon; an analytical model for evaluation of degradation rates of each component was developed and the calculation procedure was shown based on the analytical model. Each component of the mixture is degraded sequentially in order of degradation rates, and the degradation rates of each component can be evaluated by analysing a time-TOC concentration variation curve obtained experimentally. Calculated values were compared with experimental results.
Removal of COD and Nitrogen in Wastewater Using Sequencing Batch Reactor with Fibrous Packing
Authors: Fang H. H. P. , Yeong C. L. Y. , Book K. M. , Chiu C. M.
Published: May 2018

An 11-litre sequencing batch reactor (SBR) filled with fibrous packing was found to be very effective for the removal of not only Chemical Oxygen Demand (COD), but also nitrogen from synthetic wastewaters with 250-1034 mg/l of COD and 22-114 mg/l of nitrogen. As compared to the conventional SBR, mis system had a shorter cycle time by skipping the settling step. In addition, denitrification was efficiently conducted in the interior of the ‘bio-pompons', which were formed by the attached growth of biomass on the fibrous packings, even though the bulk of the reactor was under constant aeration. The system was tested at 12 loading conditions, ranging from 0.56 to 4.51 kg-COD/m3-day and from 0.04 to 0.49 kg-NH3−N/m3-day. On average, 95% of COD was removed within 2 h of aeration, while 57% of total nitrogen was removed after a retention time of 4-8 h.
Determination of the Maintenance Requirements of Activated Sludge
Authors: Chang J. , Chudoba P. , Capdeville B.
Published: May 2018

Maintenance energy plays an important role both in basic kinetic studies and in process development. Numerous studies have been devoted to the maintenance concept in various microbial fields but very few in biological wastewater treatment. Using a fermenter coupled to a mass spectrometer, we investigated the influence of the ratio So/Xo (ratio between initial substrate concentration and initial biomass concentration) on the observed sludge growth yield of an oxic-settling anaerobic (OSA) system. By measuring the substrate removed, the oxygen consumed and the carbon dioxide produced, we were able to estimate the substrate fraction used for maintenance purposes. The results indicate that at a high So/Xo ratio, a greater proportion of the substrate is devoted to maintenance thus significantly decreasing the observed growth yield. These findings are of particular importance in view of the cost associated with the disposal of excess sludge in aerobic wastewater treatment processes.
Denitrification by Immobilized Sludge with Polyvinyl Alcohol Gels
Authors: Lin Ying-Feng , Chen Kuo-Cheng
Published: May 2018

Preparations of acclimated-denitrifying sludge entrapped in phosphorylated polyvinyl alcohol (PVA) beads were used in the denitrification of wastewater. The effects of pH, temperature, and size and sludge load of biocatalyst beads on the nitrate reduction activity were examined. The operational stability of the immobilized sludge system was studied both in a batch reactor and in a CSTR. A high efficiency of denitrification (over 98%) was achieved stably in continuous operation for at least one month. Immobilization in phosphorylated PVA gel proved to be an effective, inexpensive and mild (high recovery of cell activity) method.
Potable Water by Use of Swirl Concentrators
Authors: Mashauri D. A. , Viitasaari M.
Published: May 2018

Water processing for potability purposes is a challenging and expensive exercise. In many cases raw water is in a state which demands elaborate treatment so as to produce clean water - chemically, bacteriologically and physically. The first two analyses are well known and the processes standardized to some extent. The last requirement is taken for granted - that is simple and therefore need not be considered. It is the physical requirements, for example colour, taste, smell and turbidity, that the public cares much for.

In this paper the removal of solid particles, which are the main cause of turbidity and to some extent colour and taste in water, is discussed. The process is based on water power separation mechanism through the use of swirl concentrators. The concentrator uses the fluidic power of raw water to physically separate suspended solids from the raw water thereby rendering the water potable.

Both theoretical or mathematical and physical treatments are provided.

The liquid and particle flow is calculated by a numerical model. The model's equations of motion are solved numerically for a turbulent axissymmetric system of a vortex basin. A uniform computational grid is used when estimating the finite differences for the equations of motion. The mixing length model procedure is utilized to compute turbulence. The results of the numerical model do agree, to some extent, with the measured ones.
The Management Component of the Kafr El Sheikh Water Supply Project, Egypt
Authors: Rose J. E.
Published: May 2018

The Kafr El Sheikh Water Supply Project is a comprehensive endeavour to provide the physical and institutional resources for an effective and sustainable water supply system for 2 million persons in a developing rural Governorate in the Delta region of Egypt. The paper describes the aims of the Management Component, the institutional development of an integrated water supply and sewerage company and the main activities to-date. These include training, operational improvements, health education and finance development. Further support is required until all engineering and institutional development work has been completed.