Possibilities for developing combined recycling and renewable energy production in Juva and Järna

Two ways of local recycling of te solid fraction of biowaste, one of which is combined with the production of biogas, have been studied within the BERAS-project. On-farm biogas plant treatment in Juva could also support agriculture

The K-trial. A 33-years study of the connections between manuring, soils and crops

In 1958 started a comparative fertilization trial, called the K-trial, within the frames of Scandinavian Research Circle for Biodynamic Agriculture. The trial ended in 1990. This report accounts for the results that have been collected over this 33-year long trial-period. The ambition with the trial was to develop methods of analyses that could indicate foodstuff quality. The long-term trial-period also brought along, a possibility to study the correlation of fertilization, soil and crop. The difference between a cultivation that uses organic fertilizer compared to one that uses mineral fertilizer and where both achieves comparable yield-levels can according to the results from the K-trial be summarized as: Soil - higher enzyme-activity, soil respiration and occurrence of earthworms - more deep going soil processes - considerably higher nitrogen-mineralising capability - better soil-fertility Crop - better storage efficiency and resistance against decomposition - higher grade of maturity - higher amount of leguminous plants in the clover/grass ley The results from the K-trial in this report, has been compared to the results from two ”daughter-trials”. In these trials two different systems was compared, biodynamic agriculture and conventional agriculture. The effects of these different fertilizing-systems on the quality in products in the K-trial corresponded with the results from the daughter-trials. In comparison with the conventional methods, the crude protein content was lower in the organic variants, but the quality in the protein was higher in potatoes and wheat. Resistance against decomposition and storage-quality for potatoes, was higher in the organic variants and the same applied to the starch-quality in wheat. The organic fertilisation resulted in a higher fertility in soil and crops, with higher quality in protein and starch. The differences were more difficult to determine between de variant that was fertilized with compost and the ones that received raw farmyard manure, partly because the compost was also treated with the biodynamic compost-preparations. Somewhat simplified, the differences consisted in the fresh farm-yard manure more strongly did stimulate the vegetative processes and the metabolism in soil and crop, while the compost more strongly contributed to building up the soil structure and the form of the crop. The biodynamic field-preparations effects could be determined as a positive effect on the yield in all crops, except the first harvest of clover/grass ley. The effect of the preparations on yield was largest during the years when yield-level was low. Field-preparation effects were also apparent in the more deep-going soil processes, and in higher amount-amount in the clover/grass ley. This calculated supply of nitrogen by this higher amount of amount plants amounted to approx. 16 kg N per hectare and year. The results from the K-trial indicate the demand of a discussion on issues concerning food-stuff-quality. In this report a few aspects on the concept of quality has been treated. Furthermore, formulated is also a frame of a few possible future research-fields connected to the issue of quality

Effective recycling agriculture around the Baltic Sea: background report

In this report the historical background and present situation of the plant nutrient balances and surplus of plant nutrients within the agricultural sector in the eight countries of the Baltic Sea catchments area (Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Denmark, Germany and Russia) are presented and analysed. The Baltic Ecological Recycling Agriculture and Society (BERAS) project is evaluating the consequences of converting the whole agricultural sector according to recycling principles. This analysis is being based on data from selected ecological recycling farms within the Baltic drainage area and will be presented in a series of project reports of which this is the first for Work Package 2, Effects on environment, natural resources and health

Biogas plant in Järna

The Biodynamic Research Institute in Järna developed an on-farm biogas plant integrated within the highly self-supporting farm organism, Skilleby-Yttereneby, one of the farms studied in the BERAS project. The biogas plant digests dairy cattle manure and organic residues originating from the farm and the surrounding food processing units

The potential of ecological recycling agriculture (ERA) for improved nature resource conservation and reduced environmental impacts in the Baltic Sea drainage area

By integrating crop and animal production on a farm or farms in closed cooperation combined with soil formation legume crops in balanced crop-rotations it will be possible to maximize the efficient use of nutrients in manure, minimize inputs of limited nutrient resources, minimize nutrient surpluses and reduce the input of nutrients to the Baltic Sea by more than 50 %. This will be the basis for recommendation to convert the agriculture in the Baltic drainage area

Växtnäringens flöde genom jordbruk och samhälle – vägar att sluta kretsloppen

I dag går större delen av den växtnäring som tillförs jordbruket förlorat till luft och vatten eller binds i marken. Detta innebär en kostnad för jordbruket och leder samtidigt till skador på den omgivande miljön. Jordbruket bedöms svara för över 40 procent av kväveläckaget till Östersjön. Kväveförlusterna till luften i form av ammoniak bidrar också till övergödningen och det sura nedfallet. Målsättningen att halvera kväveförlusterna från jordbruket har inte uppnåtts. Trots att det är endast en liten del av fosforöverskottet i jordbruket som läcker ut i vattendragen har även detta skadliga konsekvenser för miljön i form av övergödning av sjöar, vattendrag och hav. I föreliggande studie beskrivs växtnäringsflödena i jordbruket och orsakerna till dagens överskott av växtnäring i jordbruket analyseras. Under tidsperioden 1950 – 1980 genomfördes en specialisering i jordbruket med renodlade växtodlingsgårdar och specialiserade djurgårdar. De tidigare mer slutna växtnäringsflödena mellan växtodling och djurhållning blev brutna. I skriften beskrivs också hur en strategiförändring skulle behövas som ökade växtnäringseffektiviteten i jordbruket med mer slutna näringsflöden, mindre tillförsel av handelsgödselmedel och mindre förluster i enlighet med det koncept som utvecklats inom den ekologiska odlingen. Vi har varit flera som beräknat och analyserat alla dessa flöden och näringsbalanser. Den första studien gjordes för landets samtliga län och på olika typgårdar för år 1990. I denna första studie var det agronom Lotten Westberg som gjorde mycket av beräkningsarbetet. Finansiär denna gång var Forskningsrådsnämnden (FRN). I denna förnyade studie för år 1995 som jämförelseår var det Paul Granstedt som gjorde mycket av kalkylarbetet. Finansiär denna gång var Skogs och Jordbrukets Forskningsråd (SJFR). Jag vill med detta varmt tacka såväl medarbetare som finansiärer som har gjort detta arbete möjligt. Nu när det överlämnas till läsekretsen sker det i förhoppning att vårt arbete skall leda till en ökad förståelse för orsakerna till förlusterna av växtnäring från jordbruket, en förståelse som också kan leda till åtgärder som på sikt gör att vi får mindre utsläpp från jordbruket av kväve och fosforföreningar, en bättre resurshushållning och bättre miljö

Material and methods

This chapter introduces the cases and the disciplinary approaches and methods. The BERAS study had a case study approach, and this report presents the interdisciplinary synthesis of the multidisciplinary study. Ultimately, the BERAS study attempted to clarify the potential impacts of enhanced localisation and recycling rather than to compare the average status of the present local, organic food systems and organic farms with the dominant food systems and agriculture

Biogas plant in Järna

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Two phase continuous digestion of solid manure on-farm: design, mass and nutrient balance

During the last decade some so called ‘dry fermentation’ prototype plants were developed for anaerobic digestion of organic material containing 15-50 % total solids. These plants show added advantages com-pared to slurry digestion plants: Less reactor volume, less process energy, less transport capacity, less odour emissions. However on-farm dry fermentation plants are not common and rarely commercially available. This paper reports about an innovative two phase prototype biogas plant designed for continuous digestion of solid dairy cattle manure

Nutrient balance of a two-phase solid manure biogas plant

So called "dry fermentation" prototype plants for anaerobic digestion of organic material containing 15-50 % total solids show added advantages compared to slurry digestion plants (Hoffman 2001): Less reactor volume, less process energy, less transport capacity, less odour emissions. However on-farm dry fermentation plants are not common and rarely commercially available. Recent on-farm research (Kusch & Oechsner 2004) and prototype research (Linke 2004) show promising technical solutions for dry fermentation batch reactors on-farm. The Biodynamic Research Institute in Järna developed a two-phase on-farm biogas plant. The plant digests manure of dairy cattle and organic residues originating from the farm and the surrounding food processing units containing 17.7-19.6 % total solids. A new technology for continuously filling and discharging the hydrolysis reactor was developed and implemented. The output of the hydrolysis reactor is separated into a solid and liquid fraction. The solid fraction is composted. The liquid fraction is further digested in a methane reactor and the effluent used as liquid fertiliser. Initial results show that anaerobic digestion followed by aerobic composting of the solid fraction improves the nutrient balance of the farm compared to mere aerobic composting. Composted solid fraction and effluent together contain about 70 % of total input nitrogen and 94 % of input NH4. The manure that was merely aerobic digested contained about 51 % of total input nitrogen and 3.9 % of input NH4. Additionally anaerobic digestion improves the energy balance of the farm producing up to 269 l biogas kg-1 volatile solids or 1,7 kWh heat kg-1 volatile solids