The aim of the study was to investigate biodegradability of fat industry waste, characterized by very high contents of fatty substances (57%) and the re-sulting greasy consistency. The composting process was run under aerobic conditions using the compost heap method in three independent, simultaneously prepared compost heaps. A necessary pre-condition to ensure the effectiveness of the conducted process was to improve physical properties of the above mentioned waste by selecting an appropriate structure-forming material, providing aerobic conditions for the adequate functioning of microorganisms responsible for de-composition of fatty substances. In the conducted investigations it was essential to determine adequate moisture content of compost heaps at the beginning of the process (ranging from 60 to 75%) in order to provide appropriate water activity for the development of microorganisms and initiation of metabolite production by mesophilous bacteria, which when oxidized initiated generation of large amounts of heat, and thus a rapid increase in temperature in heaps already at the third day to 40oC, and next reaching the maximum temperature (60oC) at day 12, and the maintenance of the temperature range of 50–57oC for the next 15 days. De-termined optimal moisture contents and proportions of component materials for compost heaps contributed additionally to ...
Under applicable law (The Act on Fertilizers and Fertilization 2007) sewage sludge produced in wastewater treatment plants is treated as waste. The article presents 5 variants of alteration and management of sewage sludge from the wastewater treatment plant in Szamotuły. Some of them include the use of green mass that can be obtained as a result of urban greenery maintenance works. For the purpose of this article there was carried out a quantitative balance of sludge, taking into account different degrees of its hydration. There were also discussed the results of an experiment conducted on the semi-technical scale. The drying process took place under a plastic tunnel with a length of 10 m. Two series of sludge drying at different outdoor temperatures were carried out. The sludge drying time in conditions of high ambient temperatures (24-36˚C) was 18 days. There was also determined the dependance between hydration and drying time at lower temperatures. In the final analysis, there were employed two basic methods of sludge treatment: solar drying and composting. The introduction of new solutions removes numerous existing sludge disposal costs. The benefits will consist in the elimination of sludge disposal costs or sludge hygienisation costs. ...
In this study, composting of opium poppy processing solid waste with poultry manure and rough sawdust with five initial Carbon/Nitrogen (C/N ratio) ratio ranging from 20.45, 25.00, 29.03, 32.60 and 37.47 was carried out using fifteen-identical cylindrical stainless steel reactors, each of which has an effective volume of 100 L to determine the effects of initial C/N ratio on composting loss due to degradation (dry matter loss, organic matter loss, carbon loss, and nitrogen loss, and ammonia loss). The experiment lasted for 18.65 days. In the experiment, the temperature, electrical conductivity, pH, moisture, organic matter, total carbon (C) and nitrogen (N) contents and NH3-N were monitored. Dry matter loss, organic matter loss, carbon loss, nitrogen loss, and NH3-N loss were expressed as a function of initial C/N ratio. Results showed that the highest dry matter loss and organic matter loss existed at the CN ratio of 29.70 and 31.18, respectively. The highest carbon loss occurred at the C/N ratio of 30.83. Both nitrogen loss and NH3-N loss decreased as the C/N ratio increased. ...
