Separation methods and systems for converting high concentrations of animal wastes and other nutrient-rich organic materials into nutrients and other useful products such as struvite and potassium struvite. Advantageously, the system and methods do not require the addition of external chemicals other than an acid and a base.

Separation methods and systems for converting high concentrations of animal wastes and other nutrient-rich organic materials into nutrients and other useful products such as struvite and potassium struvite. Advantageously, the system and methods do not require the addition of external chemicals other than an acid and a base.

A gravel packing apparatus includes a base pipe defining an interior fluid conduit, the base pipe having a production section configured to provide fluid communication between an exterior of the base pipe and an interior of the base pipe, the base pipe having a blank section. The apparatus also includes a screen surrounding the production section, the screen in fluid communication with an annular region of a borehole and configured to prevent particulate matter from passing therethrough, and a filtration assembly disposed proximate to the blank section, the filtration assembly including a fluid passage extending between an exterior of the blank section and an interior of the blank section.

Methods and systems for calcining dewatered tailings and/or mine waste are disclosed herein. In some embodiments, the method comprises (i) processing dewatered tailings comprising clay minerals, (ii) calcining the processed tailings to produced calcined tailings, and (iii) altering a composition and/or one or more characteristics of the calcined tailings to produce a cementitious product. Altering the composition can include blending the calcined tailings with one or more additives, such as lime, dolomitic lime, lime kiln dust, argillaceous limestone, limestone, pulverized quicklime, ground calcium carbonate, quicklime, gypsum, natural pozzolans, artificial pozzolans, water, flow aids, or the like.

Methods and systems including processing dredge spoils to reclaim soil therefrom. The techniques may include a feed system for receiving dredge spoils, a dewatering system for removing water from the dredge spoils, and a grinder/mixer for grinding the dredge spoils from the dewatering system while mixing the dredge spoils with one or more additional materials.

Disclosed are an apparatus and a method for recovering effective resources including nitrogen and phosphorus. According to one aspect of the present embodiment, provided are an apparatus and a method for recovering effective resources, which efficiently recover resources such as methane, nitrogen, and phosphorus while minimizing the use of chemicals.

A method of processing pulp, extracted from red mud in processing bauxite, includes the following steps. The pulp is filtered to obtain a first filter cake and a first filtrate. Aluminum is leached from the first filter cake by adding, to the first filter cake, sodium hydroxide (NaOH) solution to form an aluminum-containing first slurry. The first slurry is filtered to obtain an aluminum-containing second filter cake and a second filtrate. From the second filtrate, in presence of carbon dioxide gas, first aluminum compounds are filtered out. Aluminum is leached out from the second filter cake by adding, to the second filter cake, NaOH solution to form a second slurry. The second slurry is filtered to obtain a third filter cake and an aluminum-containing third filtrate. From the third filtrate, second aluminum compounds are precipitated out which include sodium hydroaluminocarbonate and aluminum hydroxide.

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.

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.

Exemplary apparatus or method implementations for a universal feeder system configured with a transfer screw feeder within a multi-section clamshell pipe permitting access to the feed screw and pipe interior for inspection, maintenance and/or cleaning during production, without disassembly or screw removal. The clamshell screw feeder pipe provides access to the screw by opening or removing the multi-section top portion of the clamshell pipe. The top pipe section is bolted and or hinges to the bottom portion of the clamshell pipe. The number of segmented multiple clamshell top sections depends on the length of the screw. One or more clamshell top sections may be configured with an inspection port. The universal feeder system configured with a transfer screw feeder within a multi-section clamshell pipe transfers feedstock feed from one or more feed vessels to one or more reactor vessel.