A wastewater treatment plant has the task to refine the wastewater from substances that should not be released into the environment. The decomposition process can, in a simple way, be described as follows: micro-organisms breathe oxygen and eat unwanted substances. The environment in which the micro-organism lives is known as sludge and the correct amount of oxygen available in the sludge is important for the decomposition to be effective. The oxygenation of the sludge alone stands for about 30% of the plant?s energy consumption.

What makes a Swede betake himself into the Chinese wilderness? How does the Rio Convention influence a plant collector? And who will crack the nut positioned 12 meters up in the crown of a tree? There are many secrets behind the act of collecting plants. In many regards, the documentation of the collection of plants for a Swedish purpose has been unsatisfactory. The focus of the publications is on what plant species that have been found rather than information on how these plants have been collected. Only few results of experimental cultivation are available. There is no doubt that there exists knowledge that has not been publicised yet.

Svensk Växtkraft is the owner of the biogas plant in Västerås. The company is planning to increase their treatment capacity at their biogas plant. In connection to this work it is also possible to make some energy saving changes to the biogas plant. The objective of this study was therefore to make an electricity and heat survey of the biogas plant, a detailed study of the heat consumption in the sanitation step and also a comparison of energy consumption with the present sanitation method and an alternative strategy where the waste is treated in 55 °C during 10 hours (the current method is heating to 70 °C during 1 hour). The energy survey was conducted in close collaboration with staff at the biogas plant. The current during normal operation was measured, power was calculated and multiplied by the time of usage to obtain the energy consumed.

Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer (system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.

Gunnebo House and Gardens was designed during the late 18th century by architect Carl Wilhelm Carlberg as a summer residence for the wealthy merchant John Hall Sr. and his family. The garden consists of formal garden, kitchen garden and English park. For the first two parts several original drawings have been preserved and here a lot of restoration work has been carried out. This paper aims to examine how the English park might have been implemented during John Hall Sr.?s time and to create a plant scheme for the area called ?Engelska kullen? (The English hill).

This report is about the experiments with mixing of the separated water and the vacuum pump seal water at Hellisheiði power plant. This is done to prevent silica scaling and clogging in pipes and reinjection wells as well as eliminating vacuum pump seal water from the plant. The experiments were done in four stages: the first stage comprised of tests with different flows of separated water at 70°C, the second stage was carried out by mixing the separated water at 70°C and the seal water with different amounts of the seal water, the third and the fourth stages were like the first and second but with the separated water at 120°C. The results show that this method is good if the mixture is around 50/50 separated water and seal water, to control the silica scaling in the separated water and to be able to reinject the seal water with the separated water. This does not eliminate the silica scaling in all of the separated water because the amount of separated water is much more than the amount of seal water that comes from the plant. .

Better, more efficient fertilizers with great productivity and economic returns are needed, but it is important today to find fertilizers that are also sustainable. It is also important to carefully monitor their impact on the environment, including potential side-effects. In this context, the microbial communities that carry out numerous essential functions contributing to a functional ecosystem are of particular interest. The present study is a complement to a pot experiment that investigated the potential of different waste products for use as fertilizers and how they affect the microbial community. In the pot experiment, the clearest treatment change in microorganism community function was found in the fully fertilized treatment used as a positive control. The question was whether this was indirect, i.e.

The impact of the distribution in the soil volume of two farm manures on the net mineralization and immobilization processes of nitrogen were studied in an incubation experiment. Cattle slurry and broiler litter were placed in the soil with three procedures for incorporation including placement on top of the soil (TOP), in the middle of the soil (MID) and mixed homogenously with the soil (MIX). During the two weeks of incubation, few significant differences in net mineralization were seen between TOP, MID and MIX. However, there was a tendency that MIX led to a larger net immobilization of N than placement at one point (TOP and MID). This is also the result in the literature.

This study analyses the economic consequences due to ethanol production in Eastern Sweden. The analyses consider the cooperative and the farmers as one vertically integrated company. The area that found the market in this study is illustrated in figure 1. The analyses assume that all members act jointly with the objective of maximizing joint profits at the farm level as well as at the cooperative firm. A mathematical model is created to calculate the optimal use of arable land.

In order to maintain a high safety level at a nuclear power plant it is important not only to measure the reliability of the components and systems of the plant, but also to investigate how the plant responds to human actions. One of the most hazardous situations in managing a power plant is fire occurring in critical areas. This study concerns the prospect of the local fire brigade to suppress a fire that has started in one of the most critical rooms for maintaining high reactor safety. The model created gives an indication on the possibilities of succeeding in suppressing a fire. In order to get a more reliable fire fighting the following advice are given:- Let the fire brigade go rounds in the plant together with the personnel, during which recommended fire suppressing methods are determined to avoid long preparation time in an actual situation.- Prepare rooms with two subsystems to make them partly with no voltage.- Give the fire brigade better feedback from actual events on nuclear power plants.- Education and training in suppressing fires in electrical equipment.The probabilistic safety assessment strives to be as realistic as possible.

This study evaluates the retention of nitrogen and phosphorus in four newly constructed wetlands in the municipality of Falkenberg, Sweden. The four wetlands have been selected because they have been specifically constructed with the aim to reduce nitrogen and phosphorus in farming areas. The process of selecting the specific wetlands has been done in collaboration with the county administration in Halland. Through field studies in collaboration with the landowners where the wetlands are sited, the areas that provide the wetlands with water were determined. The size of these drainage areas were determined in a GIS computer program. The type of land use within the drainage areas was also determined.

Starting point to this Paper is the idea and wish to adapt the society and its different activities to a recycle society. A building area in Göteborg is planned and investigated for such adaptation. In the district named Skogaberg, about 130 households totally are planned from what 20 are blocks of flats. The idea with this project is to constitute an alternative sewage system, a Blackwater system, were the fractions of most nutrients and least pollution are separated, taken care of and utilised. The aim is to get a market and use the nutrients of the organic waste from the household in agriculture use.

This study evaluates the retention of nitrogen and phosphorus in four newly constructed wetlands in the municipality of Falkenberg, Sweden. The four wetlands have been selected because they have been specifically constructed with the aim to reduce nitrogen and phosphorus in farming areas. The process of selecting the specific wetlands has been done in collaboration with the county administration in Halland. Through field studies in collaboration with the landowners where the wetlands are sited, the areas that provide the wetlands with water were determined. The size of these drainage areas were determined in a GIS computer program. The type of land use within the drainage areas was also determined.

The Baltic Sea is one of the world?s most polluted seas. Increased discharge of nutrients due to greater populations of people, together with a slow water exchange, creates great stress on the sea. Too much nutrients leads to increased growth of algae and causes problem in the ecosystem. Even if we reduce nutrient discharge the problem still exist in the ocean. When algae dies and sinks, more nutritional substances is produced called "internal eutrophication". This phenomenon will grow in the future due to a warmer climate and the problem is spreading towards the coastal zone, which is an important site for fish recreation. By removing the abundance of algae, the nutritional and toxic substances are reduced and the algae biomass can be a future resource for biofuel production..

In the pilot plant at Hammarby Sjöstad, Sjöstadsverket, several new methods are tested in order to achieve a good use of resources. When a new technique is considered it is often the performance of the technique itself, under given conditions, that is evaluated. However, in order to evaluate the overall function the whole picture is needed. With a system analysis it becomes possible to make a comparison where all the positive aspects are put up against the negative ones, for the technique itself as well as its requirements. In this way the influence that minor components have on an entire system can be considered.This report presents a system analysis of an anaerobic membrane reactor (MBR) with a VSEP-membrane (Vibratory Shear Enhanced Process).