Microsoft word - f6_phd_plan.doc

SAFE – Graduate School of Agriculture, Food and Environment
Faculty of Agricultural Sciences, Aarhus University (safe@agrsci.dk) The PhD plan is jointly prepared by the student and the supervisors and a complete PhD plan must be submitted no later than 3 months after the beginning of the PhD study. Later amendments to the plan may be submitted in connection with the half-year evaluations. 1. Name of the PhD student
2. Project working title
The chemical and physical effects of animal slurry ozonation, pH regulation and separation 3. Project description
Background:
Livestock manure is a complex mixture from a chemical, physical and biological point of view. The content is largely dependent on the digestion of the specific feed by the individual animal. During storage the manure characteristics change continuously due to further degradation. It is therefore difficult to predict the manures behaviour upon different treatments like pH adjustments, separation and oxidation. Several manure treatment projects have hitherto been carried out by commercial companies in pilot or full scale. The pilot and full scale experiments are primarily based on trial-and-error because the fundamental understanding of the processes involved is limited. Therefore, there is an urgent need for an improved understanding of these processes in order to ensure the best possible treatment of manure. Important treatments include: pH adjustments i.e. reducing and increasing pH of the manure have been tested as an approach to solve some of the problems associated with livestock production and manure management: Reducing the pH minimizes ammonia degassing and thus has potential to reduce the emission of ammonia to the environment thereby reducing the eutrophication of natural ecosystems. However reducing pH also increase the degassing of carbon dioxide and malodorous hydrogen sulphide and volatile fatty acids (VFA). Increasing pH has been used to increase the efficiency air stripping ammonia, a technique for removing Nitrogen from manure and subsequently recollecting the Nitrogen to be re-used as fertilizer. Air stripping of ammonia has been suggested as a means to reduce the N-fertilizer value of manure and as a pre-treatment to biogas production to reduce NH3-inhibition in the process. Ozonation has been proposed as a technique to reduce the emission of malodorous compounds associated with livestock production, due to the ability of ozone to oxidize a variety of chemical substances. The target compounds for this type of treatment include malodorous compounds hydrogen sulphide, indolic and phenolic substances and steroid hormones such as estrogens. Solid-liquid separation produces a liquid fraction, along with a particulate and nutrient rich solid fraction. Separation may be performed to improve the fertilizer value of the manure or produce material for biogas production. Choosing the best possible combination of manure technologies can induce multiple positive environmental effects. These include reduced emissions of ammonia and malodorous sulphur compounds, as well as reduced loss of phosphorous from fields and an improved utilization of the nutrients in the manure. pH adjustment, ozonation and separation cause multiple changes in the chemical contents in a complex solution like manure, and in consequence such treatments will affect the efficiency of downstream treatments of the manure. Hypothesis/aim of project:
The overall aim of the project is to increase the understanding of the physical and chemical propertied of manure and to understand and predict the change caused by manure treatments like pH-adjustments, ozonation and separation and combinations thereof. This knowledge can be used to provide inputs for optimization of manure management strategies. The hypothesis is that an intelligent combination of pH adjustments, separation and ozonation can lead to environmental and economic benefits that exceed the sum of the individual benefits of these treatments. Description of methods:
Ozonation will be performed in batches. Different ozone doses will be added to liquid manures. pH regulation will be performed in batches using selected acids and bases to achieve a range of acidic and alkaline conditioned manure Separations will be performed on lab scale, using filtration, centrifugation and polymer flocculation, similar or equivalent to commercial separation types. Combinations of the treatments will be tested in lab scale. Experimental conditions will be based on results and experiences gained from of single and dual treatment experiments. Consequences of repeated treatment and intervening storage of the manure approximately corresponding to full scale manure treatments set-ups will be tested. Experiments with the full scale commercial unit “Smellfighter”, a treatment involves repeated treatment of the manure combining pH reduction, ozonation and separation of manure. The experiments will involve extrapolation of results and conclusions made from small scale experiments. Analysis will mainly focus on components in the manure (little or no measurements of emission of volatile species), Suitable methods will be applied and analysis will involve: speciation of nutrients Phosphorus, Nitrogen and Sulphur. measurements of particle size distribution and particle surface-charge density dry matter(DM), chemical oxygen demand (COD) o particle composition with respect to organic matter and nutrients o measurements of alkalinity, buffer capacity and redox. o soluble pH controlling compounds in the liquid phase like bicarbonate, sulphide, phosphate, VFA and ammonia and their equilibrium and speciation systems o insoluble and soluble odorous compounds like hydrogen sulphide, methyl Work plan:
Laboratory experiment on estrogens in cattle manure assessing the combined effect of ozonation and separation on estrogen concentrations. Laboratory experiment on the combination of pH regulation and separation to identify the effect and optimize the process of combining the two treatments. Pilot or full scale separation experiments with different separation systems on the same manure to compare effects/consequences of mechanical and chemical parameters on separation efficiency 1-2 scientific paper drafts (Estrogens in manure, the effect of separation and ozonation; The effect of pH on separation products from solid-liquid separation of manure) Lab scale study on the combined effect of acidification and ozonation to identify effect of pH on the ozonation-process and optimization of the two techniques. Travel abroad to Agriculture and Agri-Food Canada Full scale experiment on the combined effect of ozonation, acidification and separation 1-2 scientific paper drafts (The effect of mechanical and chemical parameters on separation of manure; The effect of acidification and separation followed by ozonation on manure composition,) • Full scale experiment on the environmental effects of separation, ozonation and acidification to assess the environmental consequences of the combination of treatments 1 scientific paper draft (Environmental consequences of advanced manure management) 5. Planned study periods in other research environments in Denmark or abroad. Please
indicate the period, institution and country. If the PhD plan does not comprise a study
period abroad please briefly state the reasons for this.
Period: 3 months in 2012 (period not planned yet). Institution: Agriculture and Agri-Food Canada. (colaboration w. Lucie Masse) 6. Planned dissemination of knowledge/teaching. Please indicate type, institution and
extent.
Supervision of Bachelor/Master student(s) . h 7. Time schedule (courses, stays abroad/at other institutions, publishing of results).
ozonated and separated manure pH-adjustment + separation same manure (in coop. w. Grundfos, Al2, Gea) Acidification + ozonation of manure (lab scale) Acidification+ozonation+ separation (full scale, Cleanwaste phd-students) Identifying Environmental effects (experiment/modeling) Study abroad Articles
of separation and ozonation The effect of pH on separation products from solid-liquid separation of manure The effect of mechanical and chemical parameters on separation of manure The effect of acidification and separation followed by ozonation on manure composition, Environmental consequences of 8. Date and signatures

Source: http://cleanwaste.dk/onewebmedia/RC1%20Ozonation%20and%20Separation.pdf