Trickling filter

About: Trickling filter is a research topic. Over the lifetime, 1098 publications have been published within this topic receiving 20219 citations.

Designing biological filters to eliminate odors in septic tank based on the amount of hydrogen sulfide

Abstract: Introduction: Odor emission is a common environmental problem in septic tank. The feasibility of using trickling filter to eliminate the malodorous gases from the septic tank was studied. Methods and Material: A trickling filter is set up at the outlet of the waste gases of the septic tank, which was attached to the university's cafeteria. In this investigation, the trickling filter system was used, measuring the hydrogen sulfide and ammonia concentration to control the odor and to determine the elimination capacity (EC) of filtration. Results: The obtained results showed insignificant amount of ammonia, while the concentration of H2S was recorded at 90 ppm. Empty Bed Residence Time (EBRT) in the filter represented a significant relevance with the inlet concentration and the elimination rate of H2S. There is a significant linear relationship between the mass flow rate of H2S and the amount of cooked food as well as temperature. Also a significant relationship between EC and inlet concentration of H2S was observed. The trickling filter in an optimum condition with an EBRT of 200 seconds was able to remove H2S up to 99.9%. An empirical equation is developed to design a trickling filter. Conclusions: Trickling filter is an affordable and cost-effective method to remove hydrogen sulfide from the septic tank.

Trickling Filters Successfully Treat Milk Wastes

Abstract: More data is needed by milk industry regarding successful methods of waste treatment; paper discusses volume and strength of wastes discharged, and unit loadings and efficiencies at two waste treat...

Simulated Modelling, Design, and Performance Evaluation of a Pilot-Scale Trickling Filter System for Removal of Carbonaceous Pollutants from Domestic Wastewater

Abstract: The aim of the present study is to assess the wastewater treatment efficiency of a low-cost pilot-scale trickling filter (TF) system under a prevailing temperature range of 12 °C–38 °C. Operational data (both influent and effluent) for 330 days were collected from the pilot-scale TF for various physicochemical and biological parameters. Average percentage reductions were observed in the ranges of 52–72, 51–73, 61–81, and 74–89% for BOD5, COD, TDS, and TSS, respectively, for the whole year except the winter season, where a 74–88% reduction was observed only for TSS, whilst BOD5, COD, and TDS demonstrated reductions in the ranges of 13–50, 13–49, and 23–61%, respectively. Furthermore, reductions of about 43–55% and 57–86% in fecal coliform count were observed after the 1st and 6th day of treatment, respectively, throughout study period. Moreover, the pilot-scale TF model was based on zero-order kinetics calibrated at 20 °C using experimental BOD5 data obtained in the month of October to calculate the k20 value, which was further validated to determine the kt value for each BOD5 experimental setup. The model resulted in more accurate measurements of the pilot-scale TF and could help to improve its ability to handle different types of wastewater in the future.

Biofiltration of Odorous Gas Emissions

Abstract: Biofiltration has shown its potential as an interesting treatment alternative for contaminated gas streams. Unlike conventional technologies, such as adsorption, scrubbers, and incineration, biofiltration offers effective pollution control at relatively low capital and operating costs, and without the generation of secondary pollution that may require subsequent treatment. The disadvantages of biofiltration have been the large space requirements and frequent media replacements as a result of deterioration or ageing. Extensive biofilter research and development have taken place over the past 20 years internationally, in particular laboratory experiments that address the removal of single pollutants at fairly high concentrations under constant operating conditions. In field applications, such conditions are highly unusual and the feasibility of treating complex mixtures at very low concentrations relevant to many odorous gas emissions has not received much attention. The overall objective of this thesis was to reduce the knowledge gap between laboratory studies and field conditions on the topic of biofiltration for odorous gas emissions. Various operational and process related problems, such as fluctuating flows, temperatures, and pollutant concentrations, that affected the biofilter performance by creating suboptimal living conditions for the microbes were identified. A newly designed compact pilot-scale biofilter was used in three different applications with odour problems, namely restaurant, pulp mill and wastewater pumping station. The gas streams were complex mixtures with chemically diverse contaminants whose concentrations varied significantly with time. Aldehydes were the dominant compounds in restaurant emissions, while reduced sulphur compounds, primarily dimethyl sulphide, dominated the pulp mill and wastewater emissions. Overall, very low concentrations of individual compounds were found (ppb-level), and very low or no removal of the targeted compounds was achieved in the biofilter. Limitations of the biomass density in the filter media is a plausible explanation since pollutant concentrations at the ppb-level may have been too low to build up and support the bacteria. Due to the low solubility of many identified compounds, a mass transfer limitation may also have occurred due to the prevailing short residence times. Drying of the filter medium was partly a problem, pointing to the need for an improved humidification system or using a trickling filter design. In a case study at a wastewater treatment plant, a method to evaluate odour problems was developed involving local observers in an odour panel together with operational data and weather observations. Working with an odour panel proved useful in several ways; they took an active interest in and increased their knowledge of the complexity of odour problems. However, relating the panel reports to specific events at the treatment plant proved difficult, and the reports were not always consistent with current wind directions.