Compact Treatment System Research Articles

The microbiome of two strategies for ammonia removal with the sequencing batch moving bed biofilm reactor treating cheese production wastewater.

Cheese production facilities must abide by sewage discharge bylaws that prevent overloading municipal water resource recovery facilities, eutrophication, and toxicity to aquatic life. Compact treatment systems can permit on-site treatment of cheese production wastewater; however, competition between heterotrophs and nitrifiers impedes the implementation of the sequencing batch moving bed biofilm reactor (SB-MBBR) for nitrification from high-carbon wastewaters. This study demonstrates that a single SB-MBBR is not feasible for nitrification when operated with anerobic and aerobic cycling for carbon and phosphorous removal from cheese production wastewater, as nitrification does not occur in a single reactor. Thus, two reactors in series are recommended to achieve nitrification from cheese production wastewater in SB-MBBRs. These findings can be applied to pilot and full-scale SB-MBBR operations. By demonstrating the potential to implement partial nitrification in the SB-MBBR system, this study presents the possibility of implementing partial nitrification in the SB-MBBR, resulting in the potential for more sustainable treatment of nitrogen from cheese production wastewater.

Research at Varian on applied superconductivity for proton therapy

Proton therapy is a rapidly increasing modality to treat cancerous tumors, but large-scale implementation, and therefore widespread availability for patients, is hindered by the size and upfront investment for treatment facilities. Superconducting technology can enable more compact, and therefore more affordable treatment systems, by increasing the magnetic field in the magnets for the proton accelerator (typically a cyclotron) and in the beam guidance up, over, and into the patient (the gantry). In this article, we discuss research at Varian Medical Systems Particle Therapy GmbH on various superconducting technologies for potential application in future, more compact cyclotrons and gantries. We discuss which technologies are feasible, and to what extent. We demonstrate why certain conductor choices are made, and show the development of novel new conductor and magnet technologies that will be required to enable the next generation of cryogen-free, conduction-cooled compact treatment systems. We conclude that superconductivity is certainly required for the next generation of proton treatment systems, but also that the amount of compactness that can eventually be achieved is not solely determined by the magnetic field strength that is generated in the magnets.

First full-scale combined MBBR, coagulation, flocculation, Discfilter plant with phosphorus removal in France

Abstract The suspended solids (SS) concentrations in effluent from moving bed biofilm reactors (MBBRs) used for secondary biological treatment can be up to 500 mg/L. Microscreens (Drumfilters or Discfilters) can be used as alternatives to traditional clarification or dissolved air flotation to remove SS and total phosphorus (TP). This study shows how a small-scale municipal WWTP for 5,700 population equivalent (PE) can be upgraded to 12,000 PE by combining MBBR with coagulation-flocculation tanks and a Discfilter with a total footprint of 160 m2. This long-term investigation demonstrated that even though influent turbidity (range 146–431 NTU) and flow (25–125 m3/h) varied considerably, very low effluent turbidities (below 10 NTU) could be achieved continuously. Furthermore, this compact treatment system can provide average reductions of ammonium (NH4-N) from 19 to 0.04 mg/L, COD from 290 to 10 mg/L, and TP from 4.5 to 0.3 mg/L. The results show that effluent requirements can be reached by combining MBBR, coagulation-flocculation and disc filtration at full scale, without a primary clarifier upstream of MBBR.

ELIPSE: An Innovative Technology for the Treatment of Radioactive Organic Liquids

The CEA is studying the development of processes with a sufficiently large operating range in order to propose a general treatment system and make it possible to absorb a significant quantity of radioactive liquid stocks awaiting treatment around the world. A solution may be the use of submerged plasma into which the organic liquids would be injected. Current research has demonstrated that such a technique may enable the instantaneous and complete destruction of liquids with a wide variety of constituents, such as chlorine, fluorine, or phosphorus. The ELIPSE process was designed based on the results of this research. In this process, an arc plasma torch is submerged in the core of an aqueous solution. The submersion solution offers many advantages: quenching and cleaning of combustion gases; filtering of the particles they contain; and cooling maintained for the entire process, which guarantees excellent corrosion control. An advantage of this type of design is that the gas treatment system can be reduced to a demister-condenser followed by a simple safety filter, thereby offering the additional advantage of an extremely compact treatment system. This design also allows the ELIPSE process to become by this way an embeddable process if required.The present paper will first describe the state of the art concerning this concept and secondly research currently conducted using the ELIPSE process to destroy a wide variety of liquids such as tributylphosphate, trichloroethylene, and perfluoropolyether with an efficiency of over 99% at rates of several liters per hour. The apparent absence of any corrosion observed in the treatment system would indicate that, following optimization, a universal and compact process may soon be available, which may be transportable and dedicated to the treatment of orphan waste products awaiting treatment.

OS PROCESSOS DE SEPARAÇÃO POR MEMBRANAS E SUA UTILIZAÇÃO NO TRATAMENTO DE EFLUENTES INDUSTRIAIS DA INDÚSTRIA DE LATICÍNIOS: REVISÃO BIBLIOGRÁFICA

As indústrias de laticínios são grandes geradoras de efluentes em seus processos de produção. Esse efluente precisa ser tratado antes de seu lançamento em corpos hídricos, para atender aos padrões da legislação, especialmente a Resolução nº 357/2005 do Conselho Nacional do Meio Ambiente (CONAMA) complementada e alterada pela Resolução nº 430/2011(CONAMA) que “dispõe sobre condições e padrões de lançamento de efluentes”. Os processos de separação por membranas têm ganhado destaque no que se refere ao tratamento de efluentes por meio de sistemas compactos de tratamento, pois possibilitam a geração de águas de reúso que podem ser reaproveitadas nos processos industriais. Nesse sentido, buscou-se na literature estudos na área de tratamento de efluentes de laticínios por meio dos processos de separação por membranas, com o objetivo de elucidar sobre a importância desse tipo de tecnologia no tratamento de efluentes de laticínios.

Separação sólido-líquido em efluentes da suinocultura

A produção de suínos vem aumentando muito no Brasil e a contribuição da suinocultura industrial, que se baseia nos Sistemas de Produção de Animais Confinados (SPACs), tem sido cada vez mais representativa. Na região Oeste de Santa Catarina o crescente aumento da densidade de animais está associado a um passivo ambiental de grandes proporções, principalmente em virtude dos efluentes da produção dos suínos possuírem uma matriz com altas concentrações de matéria orgânica e nutrientes. São inúmeras as alternativas de processos através dos quais se pode realizar o tratamento dos dejetos de suínos: físicos, físico-químicos e biológicos; esses processos podem ser empregados de forma conjunta e sequencial. Neste trabalho se estudou um processo de separação sólido-líquido, baseado no uso de um extrato natural de taninos para a coagulação e floculação de dejeto de suínos com posterior separação gravimétrica em flotodecantador. Realizou-se a comparação da eficiência de remoção de sólidos e de nutrientes em períodos distintos, antes e após as otimizações. As modificações realizadas aumentaram a eficiência do sistema atingindo índices de 46 a 56% de redução da Demanda Química de Oxigênio (DQO), melhor compactação do lodo e diminuição no arraste de sólidos sedimentáveis do flotodencantador.

Towards a low complexity carbon removal model for the optimal design of compact decentralised wastewater treatment systems

On-site decentralised wastewater treatment systems can provide a financially attractive alternative to a sewer connection in locations far from existing sewer networks. Operational problems and shortcomings in the design of these systems still occur frequently. The aim of this paper is to provide a low complexity (i.e. easy to calibrate) but still accurate mathematical model that can be used to optimise the operational design of compact individual wastewater treatment systems. An integrated hydraulic and biological carbon removal model of a biofilm-based compact decentralised treatment system is developed. The procedure for drafting the model is generic and can be used for similar types of wastewater treatment systems since (i) the hydraulic model is based on an N-tanks-in-series model inferred from tracer test experiments and (ii) (biofilm) respirometry experiments are exploited to determine the biodegradation kinetics of the biomass. Based on the preliminary validation results of the integrated model, the carbon removal in the system can be predicted quite accurately. While some adjustments could further improve the modelling strategy, the here presented results can already assist the manufacturers of compact treatment systems in efficiently (re)designing their systems.

Wastewater treatment using a novel bioreactor with submerged packing bed of polyethylene tape

The performance of a novel aerobic bioreactor with a specially designed submerged packing bed of high specific surface area density, made of polyethylene tape, was studied for the treatment of domestic wastewater. The reactor has a volume of 0.71 m(3) and the specific area of the packing bed was 1,098 m(2)/m(3). The operation was performed with and without effluent recycling, applying different organic loads in the range of 4.0-17.6 g COD m(-2) d(-1). No back-washings were carried out. Overall BOD(5) removals of 90-95% were obtained with organic loads of 4.0-17.6 g COD m(-2) d(-1) and HRT of 0.2-1.1 h. Overall TN removal of 69-72% was obtained at loads of 0.8-4.6 g TN m(-2) d(-1) when effluent recycling was used. The reactor allowed obtaining high quality water for urban reuse and demonstrated an effective process performance and resistance to load variations. The developed biofilm was completely penetrated by the organic matter, ammonia and oxygen, providing high removal rates. Large biomass quantities, up to 13 g dry VS/m(2), were reached in the reactor and the determined sludge yield coefficient was relatively low, of 0.25 g VSS/g COD. These results allow obtaining compact treatment systems with low sludge production and make the technology a suitable option for small wastewater treatment plants.

Direct influent filtration as a pretreatment step for more sustainable wastewater treatment systems

Within the scope of a research programme into wastewater treatment scenarios based on physical-chemical pretreatment, the application of direct influent filtration (DIF) as a first treatment step in a wastewater treatment system was investigated. The aim of the experimental research was to investigate the feasibility of DIF as a pretreatment step for advanced particle removal. With a large scale pilot-plant filter at WWTP Leiden-Noord, The Netherlands the removal characteristics for suspended and colloidal material were investigated as well as operational conditions of eight different filter configurations. From the experimental research it was concluded that filtration of raw wastewater is possible, notwithstanding the relatively short run-times due to clogging. In general, the filters produced a filtrate with a constant quality with low concentrations of solids and low turbidity. Without addition of chemicals hardly any colloids and solubles were retained, but only suspended particulates were removed. After dosage of iron or polymer, it was possible to remove more suspended matter and a high proportion of colloidal material. Finally it was concluded that DIF could be applied as a compact treatment system to produce a high quality primary effluent with a constant composition, but for practical application further research has to be done.