Heavy metals determination in manures provides benefi cial information to predict the availability and the potential contamination of environment. Therefore, a study was carried out to investigate heavy metals changes in livestock manure during a co-composting process. The metals were stepwise fractionated into exchangeable, adsorbed, organically bound, carbonate precipitated and residual forms...

To ensure quick and uniform aerobic stabilization of biowaste through domestic composting and to prevent malodorous emissions, two modifications were made to a conventional steel barrel composter by: (1) providing 0.0125 m diameter openings throughout the sides and (2) placing a 0.0254 m diameter perforated polyvinyl chloride (PVC) pipe in the middle portion of the barrel. The volume of compost...

the aim of this study was to determine the optimum mixture ratios for composting separated cattle manure and pepper plant residues. five 127 liter laboratory-scale bioreactor were used to investigate of separated dairy manure addition on the composting process of greenhouse pepper plant residues. cattle manure is considerably rich in nitrogen. however, composting with cattle manure alone is not...

In the present paper, the idea of braking energy regeneration and reusing that energy during acceleration for a refuse truck is comprehended. According to their driving cycle, the refuse trucks have a good potential for braking energy regeneration. On the other hand, hydraulic hybrid is a powertrain with high power density which is appropriate for energy regeneration. In the primary stage of th...

The fate of 16 polycyclic aromatic hydrocarbons (PAHs), targeted by the USEPA agency, has been investigated during composting of lagooning sludge. Composting shows efficient decrease of the content and the bioavailability of each PAH. Biodegradation and sorption are suggested as the main mechanisms contributing to this decrease. During the stabilization phase of composting, extensive microbial ...

It is widely known that variation of the C/N ratio is dependent on many state variables during composting processes. This study attempted to develop a genetic algorithm aided stepwise cluster analysis (GASCA) method to describe the nonlinear relationships between the selected state variables and the C/N ratio in food waste composting. The experimental data from six bench-scale composting reacto...

The effects of thermochemical pretreatment and continuous thermophilic conditions on the composting of a mixture of rice straw residue and cattle manure were investigated using a laboratory-scale composting reactor. Results indicate that the composting period of rice straw can be shortened to less than 10 days by applying alkali pre-treatment and continuous thermophilic composting conditions. T...

Composting of deer carcasses was effective in reducing pathogen levels, decomposing the carcasses and producing a useable end product after 12 months. The composting process used in this project involved enveloping the carcasses of road-killed deer in woodchips and allowing those pues with natural air circulation to sit undisturbed. Temperatures were measured and samples from the piles were ana...

Waste management planners and engineers are sometimes faced with questions of how much land, equipment, labor, and investment is required for a proposed composting operation. The numerous factors that impact process design and costs such as type of materials composted, location of facility, cost of labor, etc. make it tedious to make these assessments quickly. To address this situation, a user-...

Composting of two different types of sludge from the recycled paper manufacturing industry was carried out at laboratory scale. Physico-chemical sludge (PCS) from the de-inking process and biological sludge (BS) from the wastewater treatment plant were composted and co-composted with and without addition of a bulking material. Despite its poor initial characteristics (relatively high C/N ratio,...