Anaerobic digestion is a naturally occurring biological process in which large numbers of anaerobic bacteria convert organic matter into methane and carbon dioxide (a mixture called biogas) in the absence of air. It is a widely used biological process for treating wastewater solids. This process stabilizes the organic matter in wastewater solids, reduces pathogens and odors, and reduces the tot...

The presented work studies the possibilities of using maize silage for biogas production in laboratory as well as in full-scale conditions. From the results of long-term operation of a mixed laboratory anaerobic reactor, it follows that processing of maize silage as a single substrate is an unstable process due to the low alkalinity of silage that has to be compensated by pH adjustment. Specifi...

The performance of mesophilic anaerobic digesters of four large Italian wastewater treatment plants without primary sedimentation were studied. Only the waste activated sludge is stabilised by means of the mesophilic (35–37 8C) anaerobic digestion process. The anaerobic digesters generally worked with a hydraulic retention time in a range of 20–40 days and an organic loading rate of some 1 kg V...

Composting toilets aim to recycle excrement into safe, stable humus. Preceding this, low costs, low risks, and mass reduction should be ensured. Source separating vermicomposting toilets (SSVCs) outperformed mixed latrine microbial composting toilets (MLMCs) in all categories. MLMCs: incurred ten times greater operational costs; created 10x more operator exposure; employed no proven pathogen re...

Conventional landfills are built to dispose of the increasing amount of municipal solid waste (MSW) generated each year. A relatively new type of landfill, called a bioreactor landfill, is designed to optimize the biodegradation of the contained waste to stabilized products. Landfills with stabilized waste pose little threat to the environment from ozone depleting gases and groundwater contamin...

A correct separation of solids from liquid fraction is crucial for a successful treatment of swine manure. For this reason an in-depth study of flocculant addition on different livestock wastewaters was carried out. Two flushed swine manure matrices, namely the mixture from nursery and feeder-to-finish pigs and the feeder-to-finish slurry alone, were tested for solids and nutrients removals fro...

This study investigated the chemical and thermal properties of faecal sludge from 10 dry VIP latrines in Bester’s Camp in the eThekwini Municipality, Durban, South Africa. Faecal sludge samples were selected at different depths and from the front and back sections of 10 VIP latrines during a manual emptying process. The samples were analysed for: moisture content; volatile solids; chemical oxyg...

The sonochemical decomposition of volatile organometallic compounds produces high surface area solids that consist of agglomerates of nanometer clusters. For iron pentacarbonyl and tricarbonylnitrosylcobalt, nanostructured metals and alloys are formed; for molybdenum hexacarbonyl, the metal carbide is produced. These sonochemically produced nanostructured solids are active heterogeneous catalys...

This paper describes a GC/MS system capable of performing Volatile Organic Analysis on liquids, solids, and air. When combined with a syringe auto-injector, the system is completely automated for both volatile and semi-volatile analyses. An OI Analytical Model 4551 Vial Multisampler and an OI Analytical DPM-16 Multisampler are interfaced and then connected to an OI Analytical Model 4560 Sample ...