Processes and system are provided for digesting biosolids in a multistage digestion system. The processes and system are well suited for producing Class A biosolids and biogas containing a high content of methane. Methods and systems are also provided for recovery of phosphorus from wastewater and biosolids.

Provided is a wastewater treatment process including: (a) circulating wastewater including biodegradable organic material, between an anaerobic digester (AD) and at least one microbial electrolysis cell (MEC), the MEC including an anode and a cathode; (b) applying voltage on said anode and said cathode; and (c) discharging from said AD biogas with a methane fraction of above 70% v/v. Also provided is a biological wastewater treatment system including wastewater inlet, and (i) an anaerobic digester (AD) comprising biogas outlet, and effluent outlet; and (ii) at least one microbial electrolysis cell (MEC) including an anode and a cathode; said AD and said at least one MEC being in liquid communication through liquid circulation lines configured for at least circulating wastewater between said AD and said at least one MEC.

Provided are an anaerobic ammoxidation synergistic nitrogen removal process device of municipal sewage main and side streams and an application method thereof, comprising a municipal sewage raw water tank (1), a biological reaction pool (2), a secondary sedimentation pool (3), a sludge digestion solution raw water tank (4) and a sludge digestion solution AOB strengthening pool (5); wherein, the municipal sewage raw water tank (1) is connected with a water inlet valve (2.2) of the biological reaction pool (2) through a water inlet pump (2.1) of the biological reaction pool (2); the biological reaction pool (2) is connected with the secondary sedimentation pool (3) through a secondary sedimentation pool connection pipe (3.3); the sludge digestion solution raw water tank (4) is connected with a water outlet valve (4.1) of the sludge digestion solution raw water tank (4) through a water inlet pump (4.2) of the sludge digestion solution raw water tank (4); the sludge digestion solution AOB strengthening pool (5) is connected with an anaerobic ammoxidation region compartment of the biological reaction pool through a sludge-water mixture reflux pipe (5.8) and a sludge-water mixture reflux pump (5.11). It has the advantages of reasonability in structure design, convenience in operation, low running and maintenance cost, relatively low energy consumption, no need of an additional carbon source and the like, it can realize that short distance nitrification of municipal sewage is more stable, and it is high in low-temperature, water quantity and water quality shock resistance and can further increase volumetric load at the same time.

The present disclosure generally relates to a system for monitoring and/or controlling the delivery of one or more organic carbon compounds to a wastewater treatment system. The system comprises a bio-electrochemical sensor to monitor metabolic activity of a population of exo-electrogenic bacteria and provide an electrical output corresponding with the metabolic activity, the bio-electrochemical sensor comprising an electrode pair and a power source to deliver a voltage across the electrode pair, and an electrical output analyzer to analyze the electrical output and correlate the electrical output with a value representing the amount of the one or more organic carbon compounds in the wastewater treatment system. A method and sensor for monitoring and/or controlling the delivery of one or more organic carbon compounds to a wastewater treatment system are also provided.

Provided is a wastewater treatment process including: (a) circulating wastewater including biodegradable organic material, between an anaerobic digester (AD) and at least one microbial electrolysis cell (MEC), the MEC including an anode and a cathode; (b) applying voltage on said anode and said cathode; and (c) discharging from said AD biogas with a methane fraction of above 70% v/v.

Also provided is a biological wastewater treatment system including wastewater inlet, and (i) an anaerobic digester (AD) comprising biogas outlet, and effluent outlet; and (ii) at least one microbial electrolysis cell (MEC) including an anode and a cathode; said AD and said at least one MEC being in liquid communication through liquid circulation lines configured for at least circulating wastewater between said AD and said at least one MEC.

The present disclosure generally relates to a system for monitoring and/or controlling the delivery of one or more organic carbon compounds to a wastewater treatment system. The system comprises a bio-electrochemical sensor to monitor metabolic activity of a population of exo-electrogenic bacteria and provide an electrical output corresponding with the metabolic activity, the bio-electrochemical sensor comprising an electrode pair and a power source to deliver a voltage across the electrode pair, and an electrical output analyzer to analyze the electrical output and correlate the electrical output with a value representing the amount of the one or more organic carbon compounds in the wastewater treatment system. A method and sensor for monitoring and/or controlling the delivery of one or more organic carbon compounds to a wastewater treatment system are also provided.

Processes and system are provided for digesting biosolids in a multistage digestion system. The processes and system are well suited for producing Class A biosolids and biogas containing a high content of methane. Methods and systems are also provided for recovery of phosphorus from wastewater and biosolids.

A method of controlling a volatile fatty acid in an aqueous industrial system is provided in the present disclosure. The method includes determining a level of dissolved oxygen in process water in the aqueous industrial system and adding an effective amount of a control agent to the process water if the determined level of dissolved oxygen is above a predetermined level. The compositions and methods can lower the amount of VFA present in the aqueous industrial system.

A method and system for hydrogen production from organic material such as waste. The system includes a bioreactor for continuous anerobic fermentation to produce hydrogen in which a mixture containing a microorganism and organic material is sonicated. The system optionally includes a biomethanator connected in-line with the bioreactor.

The invention is in the field of organic sludge digestion from various sources, such as manure, sludge from a wastewater treatment plant, and an organic fraction of dredging sludge. The present method provides advanced control for serially treating aqueous organic sludge by anaerobic digestion. It further relates to dewatering of the obtained biomass.