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In 2001, the Quebec Ministry of Environment modified its waste management regulation and obliged dairy farms to treat their milk house wastewaters to prevent contamination of water courses. For small dairy farms with fewer than 60 cows, conventional technologies implied an investment of at least $15 000 to comply with the new regulation. / The objective of this master's project was therefore to develop a low cost and sustainable technology for the treatment and disposal of milk house wastewaters that would permit on-farm recycling of nutrients and water. With the help of the research results of Urgel Delisle and Ass., the new system was done by modifying existing septic tank systems on two dairy farms with 40-50 cows by installing a sediment and milk fat trap before the septic tank, and building a drained 0.45ha seepage field in a pasture or cropped field, after the septic tank. / The modified septic tank system on each farm was monitored during a three year period, which involved checking the system for clogging by digging out sections of sewer pipes after two years of operation; measuring and sampling milk house wastewaters to establish the annual nutrient load, and comparing the water quality in drainage from the seepage field to that of a nearby control field. / The milk house wastewaters produced by the farms led to an average nutrient load of 60kg TN/ha/y, 50kg TP/ha/y and 80 kg TK/ha/y. The average volume of wastewater applied to the seepage field, between 16 and 19mm/month, did not saturate the soil as no sign of gleying (reduction of iron oxides) was observed when excavating the sewer pipes. In general, soil pH decreased when milk house wastewater entered the seepage field, while the NH4-N, K and Ca concentrations increased. However, soil salinity was low (<4 dS m -1) on these farms. The soil P concentration was unchanged on one farm, but there was rapid and significant accumulation of P in the 20-60 cm depth of the soil profile on the second farm. The accumulation of milk fat inside the sewer pipes on one farm resulted from the disposal of wasted milk into the septic system, the absence of a water softener and the fact that this fat was not regularly removed from the trap. The milk fat was then flowed into the septic tank harming the correct operation of the system. Drainage water quality was similar from the seepage field of the modified septic tank system as an adjacent control field. / The low cost of system modification, about $4 400 Can., and the treatment efficiency achieved meant that the concept is feasible and offers a suitable solution for small dairy farms.

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 103-108). / xiv, 108 leaves, bound ill. 29 cm

A phosphorus rich wastewater, typical of a dairy processing site producing milk powder, was biologically treated in a continuous activated sludge reactor. A literature review indicated there was a vast amount of information on the mechanisms of the Enhanced Biological Phosphorus Removal (EBPR) process and its application to domestic wastewaters, but little successful research on its application to dairy processing wastewater. The biodegradability of the wastewater organic fractions was assessed due to their impact on the EBPR process. Continuous anaerobic fermentation tests were used to determine the concentration of volatile fatty acids that could be generated, as these are required for successful EBPR. A fermenter hydraulic retention time of 12 hours and a temperature of 35 °C generated the highest concentration of volatile fatty acids, with an acidification rate of 65% (based on 0.45µm filtered COD). To permit improved dissolved oxygen control and increased flexibility, a multi-zone reactor was designed. A fermentation stage was also incorporated prior to the activated sludge reactor. This reactor was operated with anaerobic, anoxic and aerobic zones at an SRT of 10 days and stable biological phosphorus removal was achieved. A maximum of 41.5 mg P/L was removed and phosphorus release and PHA storage occurred in both the anaerobic and anoxic zones. The soluble COD consumed in the unaerated zones (anaerobic + anoxic) totalled 484 mg COD/L on the day of the zone study (day 158). The aerobic sludge phosphorus concentration averaged 7.0% mg P/mg VSS after system optimisation. The anaerobic volume was doubled in order to increase the anaerobic consumption of volatile fatty acids. This change increased the amount of soluble COD consumption in the unaerated zones to 632 mg P/L after 40 days but did not result in a significant increase in biological phosphorus removal. In the next series of trials, the concentration of nitrogen in the wastewater was decreased and the anoxic zone removed. This change did not improve the amount of biological phosphorus removal, which was 35 mg P/L at an SRT of 10 days. The effect of different sludge retention times was then investigated. Increasing the SRT to 15 days resulted in little change in phosphorus removal (34.5 mg P/L). Decreasing the SRT to 5 days resulted in the loss of EBPR. The medium term effect on the EBPR process by removing the fermentation stage was also assessed using an AO configuration at an SRT of 10 days. The amount of phosphorus removed decreased slightly after 34 days to 34 mg P/L, but the soluble COD consumed in the anaerobic zone increased to 624 mg P/L. It was concluded that a stable EBPR process could be established when treating a dairy processing wastewater with a continuous activated sludge reactor. The biological stability was sensitive to changes in the solids retention time and the removal of the fermentation stage.

Anaerobic ponds are an established technology for treating farm dairy effluent in New Zealand. These ponds produce a significant amount of methane but because of their large size, they are rarely covered for methane capture. The removal of solids prior to entering the ponds would allow for shorter retention times resulting in smaller ponds that could be covered. However, removal of solids entails loss of organic material and thus methane production. It was proposed that improved hydrolysis of solid content prior to solids separation could increase the organic content of the liquid fraction. No literature was found describing two-stage (acidogenic/hydrolytic and methanogenic) systems which achieve hydrolysis combined with solids separation of manure slurries. Hence, the aim of the present study is to examine the feasibility of such a system. Five parameters were examined to determine favourable conditions for hydrolysis of solids and acidogenesis in farm dairy effluent. These were: 1) mixing, 2) hydraulic retention time (HRT), 3) liquid to solid ratio (dilution), 4) addition of rumen contents, and 5) reactor configuration. Continuous mixing of cow manure sludge inhibited net volatile fatty acid (VFA) production, likely due to oxygenation. By comparison, a once-daily brief stirring regime resulted in production of 785 mgVFA/Lsludge compared with 185 mg/L from a continuously stirred reactor. Mixing had little effect on soluble COD yield. HRTs ranging between 1 and 10 days resulted in greater hydrolysis yields (0.25 to 0.33 gCOD/gVSadded) compared with 0.15 gCOD/gVSadded for a 15-day HRT. It was hypothesised that the attachment of hydrolytic bacteria to solids prevented washout at shorter HRTs. In contrast, longer HRTs favoured VFA production. This may have been due to the planktonic nature of acidogenic bacteria, making them more vulnerable to washout at shorter HRTs. The effects of solid:liquid ratio on hydrolysis and acidogenesis were examined with sludge:water ratios ranging from 1:1 to 1:0.25. The addition of larger volumes of water resulted in improved acidogenesis with the 1:1 sludge:water mixture producing a liquor with 245% more VFA mass (635 mg) than reactors with a 1:0.25 sludge:water mixture (184 mg). Addition of rumen contents was shown to have little or no effect on either acidogenesis or hydrolysis. This may have been due to a masking effect of an increased organic load through the addition of undigested grass in the rumen. A mix, settle and decant (MSD) system and an unmixed flow-through leachbed separator system were trialled and compared as hydrolytic/acidogenic reactors. The MSD system produced 0.033gVFA/gTSadded and 0.315gCOD/gTSadded compared with 0.015gVFA/gTSadded and 0.155gCOD/gTSadded in the unmixed leachbed separator. It was hypothesised that improved mixing and longer solid-liquid contact times in the MSD system provided greater surface contact and transfer of organics to the liquid phase thereby enhancing hydrolysis. A two-stage (acidogenic/hydrolytic and methanogenic) system was tested at bench scale. A partially mixed leachbed separator was fed with manure slurry. This retained solids while leaching out a treated feed high in organic content to be fed into a variety of methanogenic systems. The leachbed separator produced a treated feed with a VFA concentration of 562 mg/L, 120% higher than the influent slurry (255 mg/L). Soluble COD increased 60% from 1,085 mg/L in the slurry to 1,740 mg/L in the treated feed. 20-day HRT and 10-day HRT unmixed unheated methanogenic reactors, both fed with treated feed from the leachbed separator, had lower specific methane yields (0.14 and 0.11 LCH4/gVS respectively) than a 50-day HRT reactor fed with untreated slurry (0.17 LCH4/gVS). However, both the 20-day HRT reactor and the 10-day reactor had higher volumetric methane yields (0.033 and 0.057 LCH4/Lreactor/day respectively) than the 50-day HRT reactor fed with slurry (0.024 LCH4/Lreactor/day). Gas production was shown to rise as the VFA levels in the treated feed rose. Fermentation in the leachbed followed by separation was shown to improve average gas production by up to 57% compared to separation alone. Field-scale trials of a leachbed separator system followed by a 20-day HRT methanogenic reactor were undertaken. VFA concentrations increased from 100 mg/l in the influent to 1,260 mg/l in the treated feed, while the soluble COD increased from 2,766 mg/L to 5,542 mg/L. The methanogenic reactor produced 0.08 m3 CH4/ m3reactor/day, four times higher than that which would be expected from a covered pond of the same size. This was hypothesised to be due to the increased biodigestability of the feed to the tank digester as well the increased organic loading rate. This study indicates that the use of a leachbed separator would be an effective low-tech strategy for reducing the HRT of farm anaerobic ponds, and reducing the size of covers required for biogas energy recovery.

Orientador: José Euclides Stipp Paterniani, Denis Miguel Roston / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-16T20:21:09Z (GMT). No. of bitstreams: 1 Silva_AnaCristinaFerreiraMoreirada_D.pdf: 2231913 bytes, checksum: 7fd9bb73d09c49dd9863f3975ffd68c0 (MD5) Previous issue date: 2010 / Resumo: Os efluentes de laticínios lançados nos cursos d'água provocam danos ambientais graves devido ao caráter extremamente orgânico destes resíduos. Portanto esses resíduos devem ser tratados visando à redução do impacto ambiental provocado por este tipo de atividade industrial. Este trabalho visou avaliar o desempenho e a eficiência de um sistema de tratamento de resíduos líquidos de laticínios na remoção da carga orgânica, fósforo, nitrogênio, sólidos e coliformes termotolerantes, do resíduo em uma indústria de laticínios, utilizando um sistema composto por caixas de gordura, reator anaeróbio compartimentado e leitos cultivados de fluxo subsuperficial vegetado com Typha sp. e utilizando como meio suporte brita #1, sob diferentes tempos de detenção hidráulica (3 e 5 dias) nos leitos cultivados. Como média geral na remoção de DBO e de DQO, o tratamento utilizando tempo de detenção de 3 dias conseguiu remover 98,87% de DBO e 99,77% de DQO, enquanto o tratamento utilizando 5 dias de detenção hidráulica removeu, em média, 99,51% de DBO e 99,56% de DQO. Para 5 dias de detenção hidráulica foi encontrado 3,63 mg.L-1 de O2. A redução de Nitrogênio sob todas as formas estudadas foi muito representativa, em média 88,56% de redução para o tratamento com 5 dias de detenção para o N total e 98,73% de redução de nitrato e 99,90% de redução de nitrito. A maior redução de fósforo pelo sistema foi de 96,26% para 5 dias de detenção. As concentrações de sólidos foram sempre muito inferiores aos níveis máximos permitidos pela legislação e nenhuma amostra de efluente tratado apresentou coliformes termotolerantes. Os resultados indicam que o sistema foi eficiente no tratamento de resíduos líquidos de laticínios / Abstract: The dairy effluent dumped in water courses causes serious environmental damages due to the highly organic character of these residues. Therefore these residues must be treated to reduce the environmental impact caused by this type of industrial activity. This work aimed to evaluate the performance and the efficiency of a treatment system of dairy wastewater that consisted in removing the organic load, phosphorus, nitrogen, solid and thermotolerant coliform residual in a dairy industry. This was done by using a compost system of grease boxes, a anaerobic baffled reactor and a constructed wetland of subsurface flow cultivated with Typha sp. having gravel 1 as the support means and under different timings of hydraulic detention (3 and 5 days) in the wetlands. In the treatment performed using the detention time of 3 days the media of removal of BOD and COD, was 98,87% and 99,77% respectively; while in the treatment that was performed using 5 days as the hydraulic detention time the media of removal of BOD was 99,51% and of COD was 99,56%. For the 5 day detention it was found 3,63 mg. L-1 of O2. The reduction of Nitrogen under all the forms studied was significant, an average of 88,56% of reduction of total N, 98,73% reduction of nitrate and 99,90 % reduction of nitrite for the treatment using a 5 day detention. The biggest phosphorus reduction occurred in a 5 day detention and it was 96,26%. The concentrations of solids were always well bellow levels allowed by law and no sample of treated effluent presented thermotolerant coliforms. The results show that the system was efficient in the treatment of dairy wastewater / Doutorado / Agua e Solo / Doutor em Engenharia Agrícola

Worldwide, around 17% of food waste produced in high income countries is constituted of dairy products. In Sweden, Dairy Company A has been dealing with food waste production throughout all their sites. Although it already practices actions such regarding food waste minimization such as biogas generation and animal food, reduction and prevention practices are still an area of opportunity. The aim of this study is to explore alternatives for food waste prevention in Company A CSE dairy supply chain and generate recommendations that help the company achieve a more sustainable supply chain.  This study furthermore proposes a 5-step research methodology to identify food waste causes and drivers, including data gathering mainly through interviews and analysis based on proposed frameworks in relevant literature. It was found that activities related to systematic root cause identification and information storage and sharing play a key role in improving existing practices that aim to reduce and minimize food waste production from a supply planning perspective.  The research identified and recommended not only to raise awareness, which is key to reducing food waste, but to put into a broader context how decisions taken by any planner could be influencing the sustainability of the supply chain. This could be done through the adoption of process-driven mechanisms to share relevant information as well as food waste root cause identification. / Över hela världen utgörs cirka 17 % av matavfallet som produceras i höginkomstländer av mejeriprodukter. I Sverige har Mejeriföretag A sysslat med produktion av matavfall på alla sina anläggningar. Även om det redan tillämpar åtgärder som när det gäller minimering av matsvinn, såsom generering av biogas och djurfoder, är metoder för reduktion och förebyggande fortfarande ett område med möjligheter. Syftet med denna studie är att utforska alternativ för att förebygga matsvinn i Company A CSE-mejeriförsörjningskedjan och generera rekommendationer som hjälper företaget att uppnå en mer hållbar försörjningskedja.  Denna studie föreslår dessutom en 5-stegs forskningsmetodik för att identifiera orsaker och drivkrafter för matsvinn, inklusive datainsamling främst genom intervjuer och analyser baserade på föreslagna ramverk i relevant litteratur. Det visade sig att aktiviteter relaterade till systematisk rotorsaksidentifiering och informationslagring och -delning spelar en nyckelroll för att förbättra befintliga metoder som syftar till att minska och minimera produktionen av matavfall ur ett utbudsplaneringsperspektiv.  Forskningen identifierade och rekommenderade inte bara att öka medvetenheten, vilket är nyckeln till att minska matsvinnet, utan för att sätta in i ett bredare sammanhang hur beslut som fattas av alla planerare kan påverka leveranskedjans hållbarhet. Detta skulle kunna göras genom antagandet av processdrivna mekanismer för att dela relevant information samt identifiering av rotorsak för matavfall.

With the expansion of the Tillamook Creamery, in Tillamook Oregon, to double or more its cheese production, the demand for milk presents an economic opportunity for the member dairies of the Tillamook County Creamery Association. Before area dairies can expand their herd size to increase milk production for the creamery, the problem of manure waste management and pollution control must be solved. This study considers the technical and economic feasibility of developing a centralized waste treatment and methane generation facility to treat manure generated by Tillamook County dairies. A computer program modeling animal waste anaerobic digester design served as the basis for generating cost and production estimates for several hypothetical scenarios assuming input data specific to the Tillamook situation. A follow up study was also made to determine the variability of the potential ultimate methane yield of manures from Tillamook dairies. This study indicates that the proposed system is technically feasible. The study estimates that a comprehensive treatment system could cost dairymen from $70 to $100 per cow per year to start, but the economic feasibility improves as more manure is treated and more dairies participate. A full scale system has the potential to break even economically from the sale of electricity produced by a 5 megawatt methane powered generator. With the marketing of treated solids as a high grade fertilizer the system could gross a return of $1 to $75 per cow per year, depending on the scenario. / Graduation date: 1992

Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2009. / As with any form of intensive agriculture, there are potential environmental impacts associated with the management and housing of livestock on dairy farms. Within the field of dairy farming, particular focus falls to the issue of environmental degradation of water resources, as this form of pollution is currently a major environmental issue around the world. Conventional agricultural practices involving the application of chemical fertilizers to land and crops are causing environmental problems as a result of poor management practices. Dairy wastewater and manures could however be a valuable resource for agricultural producers in the form of an alternate fertilizer for their crops. Waste application as a fertilizer is more environmentally friendly than chemical fertilizers, and could drastically reduce costs for farmers, whilst alleviating storage and management problems often associated with farmyard manures (FYM). The application of organic wastes, notably livestock manures, to land has historically been important for maintaining soil fertility on farms in terms of nutrient status and organic matter levels, as well as helping to reduce soil erosion and improve waterholding capacity. The research sought to investigate the environmental and economical feasibility of using dairy wastewater and manures as an alternative form of fertilizer within agriculture in South Africa.

The last decade has been a period of great expansion and land use intensification for the New Zealand dairy farming industry with a 44% increase in national dairy cow numbers. Intensive dairy farming is now considered to be a major contributor to the deterioration in the quality of surface and ground water resources in some regions of New Zealand. Previous research has demonstrated intensive dairy farming is responsible for accelerated contamination of wateways by nutrients, suspended solids, pathogenic organisms and faecal material. A number of common dairy farming practices increase the risk of nutrient leaching. In particular, farm dairy effluent (FDE) has been implicated as a major contributor to the degradation of water quality. With the introduction of the Resource Management Act in 1991, the preferred treatment for FDE shifted away from traditional two-pond systems to land application. However, on most farms, irrigation of FDE has occurred on a daily basis, often without regard for soil moisture status. Therefore, it has been commonplace for partially treated effluent to drain through and/or runoff soils and contaminate fresh water bodies. The objectives of this thesis were to design and implement a sustainable land application system for FDE on difficult to manage, mole and pipe drained soils, and to assess the impacts of FDE application, urea application and cattle grazing events on nutrient losses via artificial drainage and surface runoff from dairy cattle grazed pasture. To meet these objectives a research field site was established on Massey University's No.4 Dairy farm near Palmerston North. The soil type was Tokomaru silt loam, a Fragiaqualf with poor natural drainage. Eight experimental plots (each 40 x 40 m) were established with two treatments. Four of the plots represented standard farm practice including grazing and fertiliser regimes. Another four plots were subjected to the same farm practices but without the fertiliser application and they were also irrigated with FDE. Each plot had an isolated mole and pipe drainage system. Four surface runoff plots (each 5 m x 10 m) were established as subplots (two on the fertilised plots and two on the plots irrigated with FDE) in the final year of the study. Plots were instrumented to allow the continuous monitoring of drainage and surface runoff and the collection of water samples for nutrient analyses. An application of 25 mm of FDE to a soil with limited soil water deficit - simulating a 'daily' irrigation regime - resulted in considerable drainage of partially treated FDE. Approximately 70% of the applied FDE left the experimental plots with 10 mm of drainage and 8 mm of surface runoff. The resulting concentrations of N and P in drainage and runoff were approximately 45% and 80% of the original concentrations in the applied FDE, respectively. From this single irrigation event, a total of 12.1 kg N ha-1 and 1.9 kg P ha-1 was lost to surface water representing 45% of expected annual N loss and 100% of expected annual P loss. An improved system for applying farm dairy effluent to land called 'deferred irrigation' was successfully developed and implemented at the research site. Deferred irrigation involves the storage of effluent in a two-pond system during periods of small soil moisture deficits and the scheduling of irrigation at times of suitable soil water deficits. Deferred irrigation of FDE all but eliminated direct drainage losses with on average <1 % of the volume of effluent and nutrients applied leaving the experimental plots. Adopting an approach of applying 'little and often' resulted in no drainage and, therefore, zero direct loss of nutrients applied. A modelling exercise, using the APSlM simulation model, was conducted to study the feasibility of practising deferred irrigation at the farm scale on No 4 Dairy farm. Using climate data for the past 30 years, this simulation exercise demonstrated that applying small application depths of FDE, such as 15 mm or less, provided the ability to schedule irrigations earlier in spring and decreased the required effluent storage capacity. A travelling irrigator, commonly used to apply FDE (a rotating irrigator), was found to have 2-3 fold differences in application depth and increased the risk of generating FDE contaminated drainage. New irrigator technology (an oscillating travelling irrigator) provided a more uniform application pattern allowing greater confidence that an irrigation depth less than the soil water deficit could be applied. This allowed a greater volume to be irrigated, whilst avoiding direct drainage of FDE when the soil moisture deficit is low in early spring and late autumn. A recommendation arising from this work is that during this period of low soil water deficits, all irrigators should be set to travel at their fastest speed (lowest application depth) to minimise the potential for direct drainage of partially treated FDE and associated nutrient losses. The average concentrations of N and P in both 2002 and 2003 winter mole and pipe drainage water from grazed dairy pastures were all well above the levels required to prevent aquatic weed growth in fresh water bodies. Total N losses from plots representing standard farm practice were 28 kg N ha-1 and 34 kg N ha-1 for 2003 and 2004, respectively. Total P losses in 2003 and 2004 were 0.35 kg P ha-1 and 0.7 kg P ha-1, respectively. Surface runoff was measured in 2003 and contributed a further 3.0 kg N ha-1and 0.6 kg P ha-1. A number of common dairy farm practices immediately increased the losses of N and P in the artificial drainage water. Recent grazing events increased NO3--N and DIP concentrations in drainage by approximately 5 mg litre-1 and 0.1 mg litre-1, respectively. The duration between the grazing and drainage events influenced the form of N loss due to a likely urine contribution when grazing and drainage coincide, but had little impact on the total quantity of N lost. Nitrogen loss from an early spring application of urea in 2002 was minimal, whilst a mid June application in 2003 resulted in an increased loss of NO3--N throughout 80 mm of cumulative drainage suggesting that careful timing of urea applications in winter is required to prevent unnecessary N leaching. Storage and deferred irrigation of FDE during the lactation season caused no real increase in either the total-N concentrations or total N losses in the winter drainage water of 2002 and 2003. In contrast, land application of FDE using the deferred irrigation system resulted in a gradual increase in total P losses over the 2002 and 2003 winter drainage seasons. However, this increase represents less than 4% of the P applied in FDE during the lactation season. An assessment of likely losses of nutrients at a whole-farm scale suggests that it is standard dairy farming practice (particularly intensive cattle grazing) that is responsible for the great majority of N and P loss at a farm scale. When expressed as a proportion of whole-farm losses, only a very small quantity of N is lost under an improved land treatment technique for FDE such as deferred irrigation. The management of FDE plays a greater role in the likely P loss at a farm scale with a 5% contribution to wholefarm P losses from deferred irrigation.