digestate Articles
-
Model assisted startup of anaerobic digesters fed with thermally hydrolysed activated sludge
This paper presents the use of the IWA ADM1 to predict and interpret results from two full-scale anaerobic digesters fed with thermal hyrolysate (waste activated sludge with a long upstream sludge age) from a Cambi hydrolysis process operating at 165°C and 6 bar-g. The first digester was fed conventionally—though intermittently, while the second was heavily diluted through a substantial component ...
-
Effect of thermal alkaline pretreatment on the anaerobic digestion of wasted activated sludge
The effect of alkaline pretreatment of waste-activated sludge, using two models to study the sequential hydrolysis rates of suspended (Sanders' surface model) and dissolved (Goel's saturation model) solids, on the mesophilic and thermophilic anaerobic digestion rate is evaluated. The pretreatment, which reduces the size of the solids, increases the reaction rate by increasing the surface area and ...
-
An asymptotic observer-based monitoring scheme for a class of plug flow reactors
In this paper a monitoring tool is designed for a class of plug flow reactors whose mathematical model is described by a set of first-order partial differential equations with different coefficients in the convective terms. The infinite dimensional structure of such a tool is derived according to the methodology established in the design of the well-known asymptotic observer. As a consequence, it ...
-
A modified anaerobic digestion process with chemical sludge pre-treatment and its modelling
Activated Sludge Models (ASMs) assume an unbiodegradable organic particulate fraction in the activated sludge, which is derived from the decay of active microorganisms in the sludge and/or introduced from wastewater. In this study, a seasonal change of such activated sludge constituents in a municipal wastewater treatment plant was monitored for 1.5 years. The chemical oxygen demand ratio of ...
-
Thermal protection - WWTF gets ahead of the curve with thermal mass flowmeters
For the Santa Cruz Wastewater Treatment Facility (WWTF), dependability matters. Since 1989, this state-of-the-art WWTF, nestled in a shallow canyon in the coastal city of Santa Cruz, Calif., has been leading the way for renewable energy programs and environmental protection in the West. Santa Cruz WWTF generates its own electric power by using internal combustion engines that burn a mixture of ...
-
Anaerobic digestion: a new model for plant-wide wastewater treatment process modeling
Abstract: This paper describes a new anaerobic digestion model for wastewater treatment systems (MantisAD). The model has been developed specifically for plant-wide wastewater treatment modelling. That is, rather than modelling nitrogen as a series of fractions of other carbonaceous state variables, this new model includes six dedicated nitrogen state variables. This structure makes this new ...
-
Dairy shed wastewater treatment and modelling by anaerobic digestion technology
There is a growing interest in the application of Anaerobic Digestion (AD) technology to Australian dairy farms not only for the reduction of environmental pollution caused by the effluents but also for recovering bioenergy. To be able to design and operate efficient AD systems, appropriate mathematical models need to be developed to observe and analyse the anaerobic process dynamics, such as the ...
-
CFD for wastewater treatment: an overview
Computational fluid dynamics (CFD) is a rapidly emerging field in wastewater treatment (WWT), with application to almost all unit processes. This paper provides an overview of CFD applied to a wide range of unit processes in water and WWT from hydraulic elements like flow splitting to physical, chemical and biological processes like suspended growth nutrient removal and anaerobic digestion. ...
-
Biological Nutrient Removal Model No. 2 (BNRM2): a general model for wastewater treatment plants
This paper presents the plant-wide model Biological Nutrient Removal Model No. 2 (BNRM2). Since nitrite was not considered in the BNRM1, and this previous model also failed to accurately simulate the anaerobic digestion because precipitation processes were not considered, an extension of BNRM1 has been developed. This extension comprises all the components and processes required to simulate ...
-
Measuring methane at the UK`s first viable compact anaerobic digester plant
At the UK's first viable compact anaerobic digester (AD) plant aimed at local food waste treatment, a Geotech GA3000 fixed biogas analyser monitors methane (CH4), carbon dioxide (CO2), oxygen (O2) and hydrogen sulphide (H2S). The plant, a modular scalable AD system, unveiled by React Environmental in July 2012 at Llangadog, Carmarthenshire, can handle some 1,000 to 5,000 tonnes of food waste a ...
-
Energy analysis of conventional and source-separation systems for urban wastewater management using Life Cycle Assessment
This study investigates the cumulative energy demand (CED) of different systems for the management of urban wastewater, following the methodology of Life Cycle Assessment. In a hypothetical case study for an urban area (5,000 inhabitants), all relevant processes for wastewater collection and treatment and the construction of infrastructure are described in a substance flow model. The conventional ...
-
Modelling shortcut nitrogen removal from wastewater using an algal–bacterial consortium
A shortcut nitrogen removal process was investigated for treatment of high ammonium strength wastewater using an algal–bacterial consortium in photo-sequencing batch reactors (PSBRs). In this process, algae provide oxygen for nitritation during the light period, while denitritation takes place during the dark (anoxic) period, reducing overall energy and chemical requirements. Two PSBRs were ...
-
Mathematical modeling of upflow anaerobic sludge blanket (UASB) reactor treating domestic wastewater
Although the upflow anaerobic sludge blanket (UASB) reactor has been widely applied for domestic wastewater treatment in many developing countries, there is no sufficient mathematical model for proper design and operation of the reactor. An empirical model based on non-linear regression was developed to represent the physical and chemical removal of suspended solids (SS) in the reactor. ...
-
Dynamic modelling of nitrous oxide emissions from three Swedish sludge liquor treatment systems
The objective of this paper is to model the dynamics and validate the results of nitrous oxide (N2O) emissions from three Swedish nitrifying/denitrifying, nitritation and anammox systems treating real anaerobic digester sludge liquor. The Activated Sludge Model No. 1 is extended to describe N2O production by both heterotrophic and autotrophic denitrification. In addition, mass transfer ...
-
Occurrence and fate of Ascaris lumbricoides ova in biosolids in Victoria, Australia: a human health risk assessment of biosolids storage periods
Reuse of sewage biosolids in Victoria, Australia, typically involves mesophilic anaerobic digestion followed by air-drying and long-term storage to ensure removal of ova of soil-transmitted helminths (STH) such as Ascaris lumbricoides. Long-term storage degrades the biosolids' agronomic quality due to the loss of key plant nutrients and takes up large areas of storage space. The impact of ...
-
Coupling ASM3 and ADM1 for wastewater treatment process optimisation and biogas production in a developing country: case-study Surat, India
The overall performance of the Anjana wastewater treatment plant (WWTP) located in Surat, India, was assessed by coupling the Activated Sludge Model No. 3 (ASM3) and the Anaerobic Digestion Model No. 1 (ADM1). Guidelines developed by the Dutch Foundation for Applied Water Research (STOWA) were successfully applied for the determination of wastewater characteristics. Concerning the fractionation ...
-
An effective feature selection approach using hybrid particle swarm optimisation with spectral projected gradient algorithm for an up–flow anaerobic filter
Wastewater treatment plant (WWTP) helps to overcome water from excessive pollution. Chemical oxygen demand (COD) or biological oxygen demand (BOD) is the measure for the wastewater effluents. Up–flow anaerobic filter (UAF) is used for the removal and digestion of organic matter present in wastewater. In this work, the performance of the UAF with cheese–dairy wastewater was considered for ...
-
New framework for standardized notation in wastewater treatment modelling
Many unit process models are available in the field of wastewater treatment. All of these models use their own notation, causing problems for documentation, implementation and connection of different models (using different sets of state variables). The main goal of this paper is to propose a new notational framework which allows unique and systematic naming of state variables and parameters of ...
-
Melbourne water’s, Werribee wastewater treatment plant, Victoria, Australia - Case Study
Werribee Wastewater Treatment Plant The GE Jenbacher generator runs on sewage gas (a type of biogas) produced from the sites anaerobic digesters. The generator is connected, via an integrated 415V circuit panel to step-up transformer. High voltage electricity is exported via transformers to provide base load power to Melbourne Water. The plant is designed to supply Melbourne Water with its ...
-
Mathematical Modelling of Anaerobic Reactors Treating Domestic Wastewater: Rational Criteria for Model Use
Anaerobic digestion modelling is an established method for assessing anaerobic wastewater treatment for design, systems analysis, operational analysis, and control. Anaerobic treatment of domestic wastewater is a relatively new, but rapidly maturing technology, especially in developing countries, where the combination of low cost, and moderate-good performance are particularly attractive. The key ...
Need help finding the right suppliers? Try XPRT Sourcing. Let the XPRTs do the work for you