372 results about "Aerobic digestion" patented technology

An apparatus and method for treating and reusing the wastewater discharged from agricultural animal farms. The apparatus and method of the present invention is designed to be a zero discharge system in which no wastewater will be discharged or spray irrigated. The wastewater effluent is first passed through a mechanical screen were bulk solids are separated and partially de-watered. The screened effluent is then directed to a primary plastic-lined earthen lagoon where it undergoes aerobic digestion utilizing specially selected bacteria. After treatment in the primary lagoon, the wastewater effluent is used to wash the floors of the hog houses or undergoes a purification phase including solids separation/denitrification, filtration and sterilization. The solids separation/denitrification phase (clarification) preferably takes place in an anoxic environment in preferably above-ground tanks where suspended solids removal will occur as well as denitrification for nitrate reduction. The clarification process may be facilitated through use of polymer addition. The majority of solids will be sent to a plurality of drying beds for de-watering and subsequent removal.

This invention provides a waste-processing system capable of processing high-solids wastes such as manure. This invention provides a compact U-shaped digester that allows for recycling of activated sludge to improve the efficiency of the process. Efficiency is also improved through a sludge heating design that creates a current in the digester and efficiently heats the sludge. A composter is provided to further process the sludge through aerobic digestion to create usable fertilizer. Finally, one embodiment provides a turbine that is fueled by biological gases from the digester to generate heat and electricity to be used by the system.

The invention provides a method for producing biogas through high-solid two-phase three-stage anaerobic digestion by using perishable organic wastes, which comprises the following steps: the perishable organic wastes are hydrolyzed in a hydrolysis acidogenic reactor, and a mixture obtained after hydrolysis is acidified to generate a large number of organic acid products with low molecular weight; the bottom of the hydrolysis acidogenic reactor is communicated with the bottom of a methanogenic reactor through a circulation pump and a pipeline; the top of the methanogenic reactor is communicated with the top of the hydrolysis acidogenic reactor; and the acetic acid producing reaction is carried out in the methanogenic reactor and the methane producing reaction is continuously carried out. The invention can separate the hydrolysis acidogenic process from the acetic acid and methane producing process in the anaerobic digestion process so as to prevent organic acids generated by the perishable organic wastes from inhibiting methanogenesis. The device has simple processing procedure, low cost, easy maintenance and stable and reliable performance, is suitable for anaerobic digestion treatment of various perishable organic wastes, and has highly efficient and stable biogas production capacity of the perishable organic wastes through the anaerobic digestion.

The invention relates to a method for comprehensively treating municipal solid waste. The method comprises mechanical treatment steps of manual sorting, bag breaking, magnetic separation, screening with a roller, winnowing and pulpifying and biological treatment steps of anaerobic digestion and aerobic composting. By combining all the steps for use, different components in the municipal solid waste are classified according to physicochemical properties of the components and then are treated; magnetic metal, plastic paper and the like which are obtained through sorting are recycled; organic waste obtained through sorting is crushed and pulpified and then is subjected to anaerobic digestion so as to produce methane; sludge is subjected to aerobic composting so as to produce organic fertilizer; the residual inorganic substances which cannot be treated or recycled can be subjected to sanitary landfill; and odor which is produced in the waste treatment process is treated in a centralized way, and then is discharged after reaching the standard. The method has great significance for treating the increasing municipal solid waste.

A process for the production of highly purified water 44 from Fischer-Tropsch reaction water 12 includes distillation 14 as a primary treatment stage, biological treatment including anaerobic digestion 20 and aerobic digestion 22 as a secondary treatment stage, solid-liquid separation 32 as a tertiary treatment stage and a dissolved salt and organic removal stage 40 as final treatment stage.

The invention discloses a method for promoting anaerobic digestion of residual activated sludge to generate methane by a pretreatment combined electrochemical technology. The method comprises the following steps: 1) concentration treatment of sludge; 2) combined pretreatment of sludge: performing ultrasonic pretreatment of sludge and alkaline pretreatment to obtain pretreated sludge; and 3) microbial electrolysis cell coupling with anaerobic digestion of sludge to generate methane: feeding the sludge after the combined pretreatment into a MEC-AD coupling reactor and fermenting to generate methane. In the method, the pretreatment combined microbial electrolysis cell hydrogen generation technology is used for the first time, and the reduction and resource utilization of the sludge from a municipal sewage treatment plant are realized.

The invention discloses a method for promoting anaerobic digestion of sludge through microbial electrical mediation, and relates to a method for fast generating methane from organic waste biomass and at the method is used for solving the technical problems that the existing sludge anaerobic fermentation technology is difficult in sludge floc wall breakage, organic matters in sludge microbial cells is difficult to fully release to a liquid phase, and the utilization rate of organic matters of the sludge and the recovery rate of methane are low. The method comprises the following steps: I, pretreating sludge; II, performing the function microbial acclimation of an anode electrolysis flora; III, promoting the anaerobic digestion of sludge through microbial electrical mediation. According to the method, protons in a system can be more quickly converted by means of the electric mediation action of a microbial catalytic electrolysis system, complicated organic acid ingredients can be effectively converted in an electronic manner so as to eliminate the inhibition role of acid accumulation in the system, and the anaerobic digestion of sludge and the speed and yield of the generated methane can be effectively promoted. The method belongs to the fields of promoting sludge to generate methane through microbial electrolysis.

Systems and methods for integrating thermochemical processing of biomass and anaerobic digestion are provided. Light oxygenated organic compounds are produced as byproducts of thermochemical biomass processing e.g. by torrefaction and/or pyrolysis, and are converted to methane by anaerobic digestion. Thermochemical processing units may or may not be co-located with the anaerobic digestion units, with co-location providing benefits for e.g. rural agricultural enterprises.

The invention belongs to the technical field of sludge treatment and recycling and discloses a method for enhancing anaerobic digestion and methane production of excess sludge by zero-valent iron and activated carbon. The method comprises steps as follows: (1), the excess sludge, inoculated sludge and water are mixed, pH is regulated to 6-7.5, solid content of a mixture is enabled to be 8%-12%, and mixed sludge is obtained; (2), the mixed sludge, activated carbon and zero-valent iron are added to an anaerobic digestion device, and anaerobic digestion is implemented; (3), gas produced in the anaerobic digestion process is collected. According to the method, the anaerobic digestion is better promoted by adding activated carbon and zero-valent iron simultaneously; the method is simple, reaction conditions are mild, a gas producing effect is better than that of a traditional method, recycling, harmless and reducing treatment of the excess sludge of a sewage treatment plant is realized, and the method has good economic and social benefits.

The invention relates to a municipal solid waste reduction, energy regeneration and recycling method, and discloses a domestic waste comprehensive treatment method based on anaerobic digestion and hydrothermal carbonization. The domestic waste comprehensive treatment method comprises the following steps: slurry treatment, anaerobic digestion, hydrothermal carbonization, dewatering and drying. The domestic waste and kitchen waste are subjected to reduction, energy regeneration and recycling treatment, so that the domestic waste comprehensive treatment method is high in resource recycling degree, low in operation cost, clean and environment-friendly, and can ensure that pathogenic microorganisms in the wastes are completely killed, so that repugnant substances are converted and decomposed, and the domestic waste comprehensive treatment method has good economic value and social value.

Systems and methods for the treatment of lipid-extracted algae biomass and recycling nutrients are provided. The lipid-extracted algae biomass is hydrolyzed prior to anaerobic digestion, and the products generated by anaerobic digestion are further processed to yield by-products that are of use either for external use or as process inputs to carry out specific steps within an integrated algal growth and anaerobic digestion process designed to minimize economic costs, required costly inputs while improving upon system capabilities.

The invention belongs to the field of solid waste treatment and relates to a method for reducing sludge by adopting ultrasound-magnetic field coupling to disrupt sludge. The method comprises the following units: an aerobic biochemical unit is to remove organic pollutants through microbes in a biochemical tank; a sedimentation unit is to separate mud from water in a sedimentation tank; an ultrasound- magnetic field treatment unit is to disrupt rest of sludge by adopting ultrasonic wave and a magnetic filed to cooperate for more than 1 minute, wherein the frequency of the ultrasonic wave is 16-200kHz, the density of sound energy is 0.1-1.0W/mL, and the magnetic field strength is 300-20000Gs; an anaerobic digestion unit is to anaerobically digest the sludge in a digestion tank; and a sludge dehydration unit is to carry out solid-liquid separation by adopting centrifugal dehydration. The method greatly reduces the sludge disruption energy consumption, and the sludge is reduced by more than 80 percent when aerobic digestion is carried out to disrupt the sludge; in anaerobic digestion, the digestion time is reduced by more than 60 percent, the methane yield is increased by more than 35 percent, the sludge is reduced by more than 30 percent. The method has obvious economic benefits, thereby having popularization and application value.

The invention relates to a processing method for fermenting straws in a dry-process and wet-process combined way, which can realize dry-process and wet-process combined fermentation treatment of straw garbage through a straw pre-softening step, a solid-liquid primary fermentation step, a dry-process aerobic digestion and decomposition step, a wet-process anaerobic digestion step and a desulfurization and drying step. By means of the method disclosed by the invention, kitchen garbage is subjected to resource treatment safely and effectively; the harmless treatment is realized; the treatment process is free from pollution; bacterial virus can be prevented from spreading; and the method is an environment-friendly straw garbage treatment method, has good economical efficiency and is capable of realizing virtuous ecological cycle.

The invention discloses an aerobic composting method of food residue, and the method comprises the following steps: A. adding water to the food residue, performing rinsing and desalination treatment on the food residue to dilute and reduce salt content of the food residue; B. performing high-speed centrifugal dewatering treatment on the rinsed and desalinized food residue; and C. putting the dewatered food residue, auxiliary materials, biological agents and biological growth promoters in a biological reactor according to a preset proportion, and allowing aerobic digestion at high temperature to obtain an organic fertilizer. In the method, salt content and moisture in the food residue are reduced by pretreatment of the food residue, and special biological agents are used for increasing content of nutritive substances. An organic fertilizer product prepared by the method has the advantages of low moisture content, high organic matter content, low content of salt and other impurities, and high content of nutritive substances such as nitrogen, phosphorus and the like.

The invention discloses a method for producing biogas through anaerobic digestion of fruit and vegetable waste, and belongs to the field of high-efficiency recycling of organic solid waste. The fruit and vegetable waste is firstly subjected to acidification as well as a high-efficiency extrusion process to realize solid-liquid separation, and then a solid-state product and a liquid-state product are treated respectively. Solid-state residue is subjected to secondary reinforcing acidification to enter a high-efficiency anaerobic digestion methane production reactor together with a liquid-state acidification product; and meanwhile, effluent water of the methanator is used as reflux liquid to be circulated in a solid-state residue secondary reinforcing hydrolytic acidification reactor to speed up the hydrolytic acidification reaction. According to the method, high-efficiency transformation of the waste is realized, and the effluent water in the methanator is pumped into the secondary reinforcing acidification reactor for recycling. The method has the advantages of high treatment rate, high gas production rate, short period, capability of realizing continuous stable gas production, no wastewater discharge and the like.

The invention relates to a treatment method of organic solid waste. The treatment method comprises the following steps of: homogenizing the organic solid waste and then preheating, carrying out a thermal hydrolysis reaction on the preheated organic solid waste, then pushing the material into a depressurization tank and a buffer tank to be subjected to primary depressurization and secondary depressurization and then temporary storage, then carrying out heat exchange on the material, carrying out anaerobic digestion on the material subjected to heat exchange, carrying out vacuum degassing treatment on digested sludge in a digested sludge tank, dehydrating the treated digested sludge to form dehydrated sludge, conveying the dehydrated sludge to a drying room to be dried, and producing dried biogas residue. According to the treatment method of the organic solid waste, high temperature hydrolysis and anaerobic digestion technologies are adopted, the problems that resource is wasted when a burning method is adopted and secondary pollution can be easily caused when a burying method is adopted can be avoided, digestive efficiency in follow-up anaerobic digestion is improved, standing time of an anaerobic digestion process is also reduced, and sludge subjected to anaerobic digestion is subjected to vacuum degassing, so that carbon dioxide and ammonium nitrogen in the digested sludge can be effectively removed, and sludge dehydration efficiency is improved.

A process for effecting anaerobic digestion of plant biomass, which entails the step of anaerobically digesting plant biomass with at least one species of rumen microorganisms.

The invention relates to a dry and wet combined digestion treatment method for livestock manure and straw. The method mainly comprises steps as follows: mixing a separation liquid after separation of cow dung with an inoculum, and performing wet anaerobic digestion on the mixture to produce first biogas and a digestion liquid; mixing and turning the straw and the livestock manure except the cow dung to obtain a first mixed material, mixing the first mixed material with the digestion liquid to obtain a second mixed material, and performing dry digestion treatment on the second mixed material to produce second biogas, biogas slurry and biogas residues; collecting and feeding the first biogas and the second biogas into a power generating set after desulfurization and dehydration; feeding the biogas residues into an organic fertilizer production line, and recovering the biogas slurry to the dry anaerobic digestion process for recycling. According to the method, dry and wet combined digestion is adopted, dry aerobic digestion is performed before dry anaerobic digestion, meanwhile, backflow of leachate is performed, mutual contact and actions among the material, microbes and moisture are enhanced, and the problems of crusting of materials, thickening of fermentation broths and difficulty in mass and heat transfer during dry fermentation are solved.

The invention discloses a resource utilization and treatment method of livestock breeding wastewater, which comprises the following steps of (1) producing biogas through anaerobic digestion, (2) deslagging, (3) performing biological aerated filter (BAF) biochemistry, (4) disinfecting, and (5) manufacturing an organic fertilizer. According to the method, an anaerobic digestion biogas producing technology, a BAF technology and a disinfection technology are combined, the livestock breeding wastewater is taken as a resource and subjected to anaerobic fermentation treatment, the biogas is produced, the wastewater after the biogas is produced is subjected to solid-liquid separation, solid slag serves as a raw material for producing the organic fertilizer, the organic fertilizer is produced, and the wastewater is recycled after the BAF technology and disinfection and is discharged up to a standard, so that the treatment effect is good, the energy consumption is low, the resource is comprehensively utilized, and the method has economic benefits.

The invention relates to a method for promoting hydrolysis of sludge by using calcium peroxide and increasing effect of anaerobic digestion of sludge, which comprises the following steps: 1)a calcium peroxide processing unit: placing the calcium peroxide in the sludge, wherein the mass ratio of calcium peroxide to sludge is 0.01: 1-0.6:1, reacting for 1-24 hours, and hydrolyzing the sludge; and 2)an anaerobic digestion unit: after processing the calcium peroxide, performing anaerobic digestion on sludge under the effect of anaerobe and amphimicrobe in an anaerobic digestion tank, rapidly using an organic compound in the sludge, conversing to methane, carbon dioxide and water, increasing the sludge biogas output and then realizing the quantitative reduction. Compared with the prior art, the method for promoting hydrolysis of sludge by using calcium peroxide and increasing effect of anaerobic digestion of sludge has the advantages of low cost, shortened digestion time and easy enforcement.

The invention discloses a method for improving the sludge anoxic/aerobic digestion property by utilizing ultrasonic pretreatment. The method comprises the following steps of: supplying sludge to a sludge anoxic/aerobic digestion reactor and providing an anoxic/aerobic environment through intermittent aeration, wherein the sludge retention time is 12 days, 24 hours form a period, the aerobic time is 12 hours, the anoxic time is 12 hours, 8.3 percent of digested sludge is discharged every day, and sludge which is equivalent to the discharged sludge and pretreated through ultrasonic waves is input every day. In the invention, low-energy ultrasonic pretreatment and sludge anoxic/aerobic digestion are combined, thus the sludge is cracked to a certain extent, the bioactivity of the sludge is enhanced, and the anoxic/aerobic digestion property of the sludge is improved; compared with a technology singly adopting sludge anoxic and aerobic/anoxic digestion or the traditional ultrasonic-aerobicdigestion technology, the method has the advantages of improving the sludge digestion efficiency and shortening the digestion time; and the method also has the advantages of reducing the aeration energy consumption and saving the energy expense.

The high temperature aerobic sludge digesting apparatus has sludge circulating system comprising sludge circulating pipeline, sludge circulating bump and sludge flowmeter; sludge aerating system comprising aerating pipeline, aerating bump and gas flowmeter; and digesting pond covered with heat insulting material. The sludge jetting section of the sludge circulating pipeline is set horizontally in the bottom of the digesting pond, the aerating section of the aerating pipeline is set below the sludge jetting section, sludge defoaming pipeline is located below the gas exhausting pipeline, the gas valve of the defoaming pipeline is connected to the aerating pipeline, and liquid sludge valve is connected to the sludge circulating pipeline. The present invention has separated sludge aerating system and sludge circulating system, conventional aerating process and direct defoaming.