Co-digestion of cultivated microalgae and sewage sludge from municipal waste water treatment.

In this study two wet microalgae cultures and one dried microalgae culture were co-digested in different proportions with sewage sludge in mesophilic and thermophilic conditions. The aim was to evaluate if the co-digestion could lead to an increased efficiency of methane production compared to digestion of sewage sludge alone. The results showed that co-digestion with both wet and dried microalgae, in certain proportions, increased the biochemical methane potential (BMP) compared with digestion of sewage sludge alone in mesophilic conditions.

Phosphorus in soil treatment systems: accumulation and mobility.

Septic tanks with subsequent soil treatment systems (STS) are a common treatment technique for domestic wastewater in rural areas. Phosphorus (P) leakage from such systems may pose a risk to water quality (especially if they are located relatively close to surface waters). In this study, six STS in Sweden (11-28 years old) were examined.

Hazards for farmers with disabilities: working in cold environments.

In consequence of working in cold environments, agricultural workers may be exposed to higher risk of cold-related injuries, compared with the general population. These injuries can include tissue damage due to the exposure to subfreezing temperatures, more generalized symptoms caused by hypothermia, and secondary injuries caused by impaired performance. Risk of cold injury is increased for older workers and for those with disabling health conditions, both of which occur in above-average numbers in agriculture.

Cleaning effectiveness of chlorine-free detergents for use on dairy farms.

A method for evaluating cleaning effect based on Bacillus cereus spores was developed and tested in a model system designed to resemble actual farm conditions. A test rig with four removable sampling plates was mounted in a milk line. The plates were attached at the end of T-junctions protruding either 1·5 or 3-times the milk pipe diameter from the main loop to reflect different levels of cleaning difficulty.

Co-digestion of energy crops and the source-sorted organic fraction of municipal solid waste.

The biological and technical performance during co-digestion of energy crops and the source-sorted organic fraction of municipal solid waste has been investigated at laboratory and pilot scale. A 50:50 (TS-based) mixture of energy crops and organic waste reached a loading rate of 6.0 gVS L(-1)d(-1) with a methane yield of 0.

Methods for determining the presence of slurry on the crop and in the upper soil layer after application to grassland.

Slurry injection in grassland may lead to lower ammonia losses and enhance silage quality compared to surface spreading. In order to evaluate the performance of different slurry injectors, there is a need for methods which measure the degree of crop contamination and the position of the slurry in the soil after spreading. The aim of this study was to identify and test possible methods.