Sewage sludge, which is a semi-solid material, is obtained as a byproduct of municipal wastewater treatment [1]. Producing biogas from sewage sludge by the means of conventional anaerobic digesters has an energy conversion efficiency of about 33–50%. Thus, more than 50% of sludge energy content remains trapped in digested sludge (digestate) [2].
Recovery of nitrogen-fertilizer from centrate of anaerobically digested sewage sludge via gas-permeable membranes. S. P. Munasinghe-Arachchige P. Cooke N. Nirmalakhandan. Environmental Science, Engineering. 2020; 22. Save. Nitrogen-fertilizer recovery from urban sewage via gas permeable membrane: Process analysis, modeling, and …
Contaminants in sludge can, however, nullify the benefits. Polycyclic aromatic hydrocarbons (PAHs) are a class of persistent organic pollutants, if present, can pose health risks by virtue of their carcinogenic potential and persistence in soil. The present study deals with profile analysis of PAHs in digested sewage sludge of a megacity, Delhi.
The commonly used disposal methods for sewage sludge are agricultural spreading, landfills, composting, anaerobic digestion, recycling as a construction material, …
Sewage sludge, which is a semi-solid material, is obtained as a byproduct of municipal wastewater treatment [1]. Producing biogas from sewage sludge by the means of conventional anaerobic digesters has an energy conversion efficiency of about 33–50%. Thus, more than 50% of sludge energy content remains trapped in digested sludge (digestate ...
Sludge source. A dewatered and digested sludge sample was collected from a sewage treatment plant purifying the domestic sewage of G city in Korea (population 230,000). The plant utilizes an anaerobic–anoxic–oxic process at a flow rate of 75,000 tons/day, anaerobically digesting and dewatering sludge before disposal.
Anaerobically digested sludge (ADS) collected from the Sha Tin Sewage Treatment Works, Hong Kong had a pH of 7.45, EC of 14.39 mS cm −1, salinity of 8335 ppm and a low ORP of −183 mV indicating the reductive environment of the sludge. The content of TS and OM were 2.05% and 42.5%, respectively while the CST and SRF of the sludge were 27 s and …
Metal forms in sewage sludge were fractionated by a sequential selective extraction method. In this study, the procedure shown in Table 2 was employed (Stover et al., 1976).The extraction of heavy metals from the sludge was carried out by shaking a centrifugal tube containing the extraction reagent and the sludge in the ratio shown in Table 2.The …
Sewage sludge incineration reduces the volume of the material to be disposed of, completely destroys pathogens, decomposes most organic chemicals, and recovers the small amount of heat value contained in sewage sludge. The residual ash is a stable, relatively inert, inorganic material that has just 10 to 20% of the original sludge's volume. ...
The number of pathogenic organisms in sewage sludge can be significantly reduced or eliminated by applying appropriate sludge treatment processes (i.e., digestion, …
The high ash content is the most important factor preventing hydrochar from ADE of sewage sludge from being used as fuel (Wang et al., 2019), and what makes it more appropriate to be used as soil amendment. The hydrochar produced from ADE of sewage sludge had ash content between 52.3% and 67.8%.
This study is the first to show that biochars from raw and digested sewage sludge can be used as effective sorbents for PFAS in most environmental contexts, with efficiencies similar to or better than those of AC. High porosity in the right size range and carbon content were probably the most important parameters responsible for the high ...
This study has been performed to better understand the effects of several common variables when upscaling HTL of digested sewage sludge from small scale (25 mL reactors) to bench scale (5.3 L ...
The use of composted sewage sludge (CSS) and centrate as alternatives to synthetic fertilizers in rice cultivation holds great promise. This study aims to determine the effects of varying doses and timings of centrate derived from anaerobically digested sewage sludge on rice yield, nutrient quality, and soil fertility when applied as a topdressing to rice fields fertilized …
Struvite recovery is an ideal way to simultaneously recover phosphate (P i) and ammonia from digested sludge.A full-scale plant to recover struvite directly from digested sludge was implemented at Higashinada Wastewater Treatment Plant (WWTP) having the sewage treatment capacity of 241,500 m 3 /day in Kobe City. The struvite recovery plant has …
in the raw and the digested sewage sludge were smaller than 0.1 mm (Mahmoud et al., 2006). Anaerobic digestion conditions have a substantial influence on the sludge physical .
Hydrothermal carbonization (HTC) is a treatment technique with great potential for sanitizing digested sewage sludge (SS) and converting it into valuable products. In particular, phosphorus (P) recovery from hydrothermally carbonized SS has attracted special attention in recent years. This work aims to examine the leaching efficiency of P and ...
In this paper, hydrochars and pyrochars were produced at 260 °C under different residence times (2 and 4 h) using anaerobic digested sewage sludge (SSL) as initial feedstock. The effect of reaction time on the fuel properties of hydrochars and pyrochars was evaluated. Moreover, the combustion kinetics of raw SSL and the derived pyrochars and hydrochars …
Digested sewage sludge (wet or dewatered) and sewage sludge ash (mono-incinerated) are the preferred streams for P recovery within a WWTP due to their high P recovery potential (max. 90% of the WWTP inflow P). However, the enforced leaching of P from the sludge leads to simultaneous undesirable dissolution of metals and organic pollutants ...
From digested sewage sludge sampled in Espoo, 60% of all phosphate could be recovered in the magnetic fraction (Wilfert et al., 2017). Vivianite has been directly applied as a slow release fertilizer, however, the fertilizer value of iron phosphates has been discussed controversially ...
A process to improve anaerobic biodegradation of wastewater treatment sludges is investigated. Recalcitrant organic compounds which are contained in biologically stabilized digested sludge become biodegradable by partial oxidation using ozone and ozone in combination with hydrogen peroxide respectively. By oxidation with ozone, cell walls of …
Single samples (n = 1) of anaerobically stabilized sewage sludge (digested sludge) were collected from eight municipal waste water treatment plants (plants A–H, see Table S1) in the greater Zürich area in 1993, 2002, 2007 and 2012 (2008 instead of 2007 for PFOS and PFOA). The treatment plants served between 4000 and 115,000 people.
Nevertheless, HSAD of sewage sludge poses several challenges due to structural and rheological characteristics of dewatered sludge and to toxic compounds originating during (H 2 S, NH 3, siloxanes, volatile organic compounds) and before (polyelectrolytes added prior to dewatering) the anaerobic treatment. This work critically reviews HSAD of ...
Anaerobically digested sludge, dehydrated by: Plate press filter—solid content from 30 to 40%. Belt press filter—solid content from 16 to 25%. ... Anaerobic digestion can reduce the concentration of volatile solids in the sewage sludge by up to 60%. The treatment, disposal, and reuse of WWTPs sludge are gaining more and more expression on ...
The sludge sample in the 120 L tank was homogenised by stirring using a Lightnin open tank mixer (Fig. 1).The mixer consists of two sets of A310 high performance three blade impellers of 160 mm diameter mounted on the shaft 240 mm apart.Two or three small samples (∼200 g) of the sludge were collected and weighed before being dried in an oven at 105 °C …
In the present study, LCA of different sewage sludge anaerobic digestion processes was conducted. The four processes were evaluated in terms of their environmental, …
For plants with chemical P-elimination, the most preferred P-recovery pathway is from the digested sewage sludge or sludge ash due to highest recovery potential (max. 90% of the WWTP inflow P), dealing with more concentrated streams, decoupled from the wastewater treatment process. The main disadvantage, however, is that the phosphorus bound ...
High-solid anaerobic digestion (HSAD) of sewage sludge is a promising alternative to conventional anaerobic digestion (AD) as it reduces treatment volumes, …
Thermochemical conversion of sewage sludge was proven as a useful method for waste management. Moderate temperatures in the absence of oxygen (pyrolysis) and hydrothermal carbonisation (HTC) performed in the presence of water, under autogenous pressures, were selected to treat the same sample of anaerobic-digested sewage sludge …
Digested sewage sludge has been reported to be rich in organic materials such as cellulose, hemi-cellulose and lignin (Romdhana et al., 2009) and is generally denoted as biomass owing to its properties. The main reason for the increasing global interest in energy recovery using sewage sludge is the energy consumption associated with discarding ...
To achieve this, the sewage sludge samples that were taken from the decanter outlet of the WWTP were spiked with pharmaceutical compounds at concentrations of 100 μg/kg and 1000 μg/kg. After adding 10 mL of acetone, the suspension was shaken on a mechanical shaker at 220 rpm for 30 min. ... Before digested sludge is applied to agricultural ...
1.. IntroductionManagement of sewage sludge is a challenging issue for water industries. The direct disposal of the sludge to the environment has been found to impact on the environment and human health, due to the presence of heavy metals, pathogens and pesticides in the sludge (Parr et al., 1978, Singh et al., 2004).Methods like incineration of dried sludge to …
