TECHNOLOGY FOCUS - MECHANICAL ENGINEERING - Preferred device: The anaerobic digester system includes pressure controller(s) and temperature controller(s). The pressure controller(s) has actuator for the pressurizer, and a pressure monitor. The temperature controller(s) is a coil inside the digester, and/or a jacket outside the reaction vessel. It has recirculating fluid source outside the reaction vessel. The recirculating fluid source is solar water heater, gas-powered water heater, steam generator, or heat exchanger. The system also has vessel(s) for preparing a feedstock slurry, a feedstock particle size reducer, and storage tank(s) for receiving the enriched effluent. The storage tank(s) includes a scum storage tank, a supernatant storage tank and a sludge storage tank. The gas processor(s) is gas scrubber, gas compressor, gas separator, gas treater, and aerial cooler.The agitator is a fluid recirculator, gas recirculator, sparger bar, mechanical agitator, gas bubbler, aerator, and/or fluid stream. The pressurizer is of the feedstock slurry feeder, external compressed gas source, fluid inlet, sparger bar, gas recirculator, or fluid recirculator. The system includes a gas recirculation system comprising gas separator for reducing methane from a discharge gas received (in)directly from the anaerobic digester to form a methane-reduced gas which is subsequently fed (in)directly back into the anaerobic digester. It also has fluid recirculation system for adding scum, sludge, supernatant or effluent (in)directly back into the anaerobic digester. It also has an internal combustion engine, electrical current generator, electric engine, water heater, furnace, air conditioning unit, ventilation fan, conveyor, pump, heat exchanger, and fuel cell. The configuration of the anaerobic digester system permits batch, semi-continuous or continuous operation.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred components: The gas is methane or carbon dioxide. The feedstock slurry comprises 1-90 wt.% solids. The aqueous slurry of cellulose-containing feedstock comprises animal tissue, biomass, fish tissue, plant parts, fruits, vegetables, plant-processing waste, animal-processing waste, animal manure, animal urine, mammalian manure, mammalian urine, solids isolated from fermentation cultures, bovine manure or urine, poultry manure or urine, equine manure or urine, porcine manure or urine, wood shavings or chips, slops, mostos, shredded paper, cotton burrs, grain, chaff, seed shells, hay, alfalfa, grass, leaves, sea shells, seed pods, corn shucks, weeds, aquatic plants, algae, and/or fungus. The enriched effluent comprises organic acid, protein, carbohydrate, charcoal, and carbon black.    TECHNOLOGY FOCUS - BIOLOGY - Preferred microbes: The anaerobic microbe is methanogenic bacterium. It is psychrophilic or thermophilic. It is particularly Clostridium spp., Bacillus spp., Escherichia spp., Staphylococcus spp., Methanobacter (Mb.) omlianskii, Mb. formicicum, Mb. soehngenii, Mb. thermoautrophicum, Mb. ruminatium, Mb. mobile, Mb. methanica, Methanococcus (Mc.) mazei, Mc vannielii, Mc. mazei, Mb. suboxydans, Mb. propionicum, Methanosarcina (Ms.) bovekeri, Ms. methanica, Ms. Alcaliphilum, Ms. acetivorans, Ms. thermophilia, Ms. barkeri, Ms. vacuolata, Propionibacterium acidi-propionici, Saccharomyces cerevisae, S. ellipsoideus, Clostridium propionicum, Clostridium saccharoacetoper-butylicum, or Clostridium butyricum.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred components: The gas is ammonia, hydrogen, or hydrogen sulfide. The enriched effluent comprises nitrogen-rich fertilizer, feed additive, insecticidal mixture, ammonia, amino acid, mineral, and insect repellant.