An anaerobic digestion system may include a material grinding/pulping portion, a hydrolysis portion arranged downstream of the grinding portion, a multiple chamber anaerobic reactor arranged downstream from the hydrolysis portion and including a gas collection and reintroduction system, a collection system for collecting digestate and gas from the anaerobic reactor.

A waste treatment process utilizes a two-stage digestion process with a thermophilic digester, a heat exchanger, and a mesophilic digester. The pH of the thermophilic digestate is increased by removal of carbon dioxide with an air stripper, or by adding a pH increasing reagent upstream of the heat exchanger. The pH adjustment of the digestate protects the heat exchanger and downstream equipment and processes from struvite formation. A struvite reactor may be located in various locations downstream of the heat exchanger to produce a treated digestate or effluent that contains struvite, which can optionally be recovered for beneficial use.

An anaerobic digestion system may include a material grinding/pulping portion, a hydrolysis portion arranged downstream of the grinding portion, a multiple chamber anaerobic reactor arranged downstream from the hydrolysis portion and including a gas collection and reintroduction system, a collection system for collecting digestate and gas from the anaerobic reactor.

Disclosed herein is a process for the treatment of wastewater for biosolids reduction and biogas (i.e. methane) generation where a wastewater is provided to a first reactor which is operated under anaerobic conditions, a hydraulic/solids retention time of from 0.1 to 1 day, a temperature of from 30 to 70° C. and a pH of from 6.5 to 10, with the effluent of the first reactor passing to a second reactor which is operated under anaerobic conditions, a hydraulic/solids retention time of from 3 to 10 days and a temperature of from 30 to 70° C. The process may further comprise feeding an effluent produced from the second reactor to a third reactor operated under anaerobic conditions, a hydraulic/solids retention time of from 3 to 20 days and a temperature of from 30 to 70° C.

The Biopowerplant is a system that integrates the generation of carbon-neutral energy through the cultivation and conversion of microalgal biomass, with sewage sanitation and environmental carbon recovery, with the additional and secondary production of biofertilizer, biofuel, water for reuse. This system integrates a suboptimal anaerobic digestion subsystem focused on the generation of biogas, the processing of the resulting digestate through a microalgal consortium culture subsystem with biofilm induction and smooth decreasing gradient of light radiation, and the transformation of the generated microalgal biomass into syngas through a subsystem of evaporation, torrefaction, pyrolysis, gasification, and combustion in separate chambers. The syngas and methane from the biogas are subsequently used as fuel in an electric power generator capable of operating with mixed gases. The biogas generation process is enriched through the recirculation of the microalgal biomass supernatant, the residual heat from the syngas generation subsystem, and the heat transferred from the combustion gases of the electric generator. The residual sludge from the biogas generation subsystem is recirculated towards a longitudinal biopile subsystem, where it acts as an anaerobic medium compared to the aerobic medium that constitutes the concentrated microalgal biomass, and both streams are mixed to be transformed into the syngas generation subsystem. Input inflows for system operation are mainly sewage, and optionally seawater and/or leachate. The inflows must be bioaugmented with a microalgal consortium dosed automatically by a Compact in situ bioaugmentation system, preferably more than 3 kilometers before the inflow enters the system.

The disclosure relates to anaerobic digestion of liquid waste streams. In one embodiment, the system for treating liquid waste comprises: an acid forming chamber; a plug-flow methanic chamber downstream from the acid forming chamber; and a weir structure provided between the acid forming chamber and the methanic chamber.

The present invention relates to a water treatment system comprising a pre-filtering device receiving water, such as waste water, to be treated and providing a filtrate, and a biological treatment device being fluidic connectable to or in fluidic connection with the pre-filtering device for receiving the filtrate from the pre-filtering device. The biological treatment device is adapted to perform a biological treatment of the filtrate and to provide sludge solids. The pre-filtering device is a cake filtration device having a filtration cake wherein the filtration cake is being provided by deposition of solids from the sludge formed in the biological treatment device. A water treatment process employing the system and a method of forming a filter cake are also described.

The invention relates to a process for separating off and/or recovering nitrogen compounds, in particular for separating off ammonia and/or recovering or producing nitrogen fertilizer, from a liquid or sludge substrate, in which a liquid or sludge substrate is introduced into a degassing vessel to which subatmospheric pressure is applied and ammonia gas formed is introduced by means of a vacuum pump into at least one scrubber which is located downstream of the degassing vessel and to which subatmospheric pressure is applied and into which acid is introduced, wherein the acid or an ammonium salt-containing liquid obtained in the at least one scrubber is taken off from the at least one scrubber, cooled and subsequently sprayed back into the at least one scrubber. The invention further relates to a plant for carrying out such a process.

The invention relates to a method for treating organic waste, in particular to a method for treating sludge from wastewater treatment plants, in order to produce power and/or hygienized organic matter, including a first step of mesophilic or thermophilic digestion (13) of at least one fraction of a stream of organic waste, and comprising the following steps: dehydrating (15) all of the digested and non-digested waste; aerated thermal hydrolysis (16) of the dehydrated waste, including an injection of an oxidizing agent in a quantity lower than the stoichiometric quantity for oxidizing organic matter, and setting to the required temperature by a heating means; and a second mesophilic or thermophilic digestion (17) of the stream of hydrolyzed waste.

A waste reduction system that utilizes organic solids suspended in a waste stream to produce carboxylic acids, which can then be employed as an input to a microbial fuel cell or other biological processes to further enhance biogas production, is provided. The organic waste stream influent undergoes a multistage fermentation process in which fermentative microorganism metabolize the organic waste materials and produce one or more carboxylic acids, especially short chain fatty acids. The carboxylic acids serve as a food source for bacteria within an anode compartment of an MFC that generates useable electricity therefrom.