A new integrated method to capture polluted CO.sub.2 using CaO produced from phosphogypsum calcination using sulfur as non-CO.sub.2 fuel where (1) both pollutants of phosphogypsum and CO.sub.2 are transformed into environmentally neutral or useful products such as limestone or clinker and sulfuric acid; (2) low-CO.sub.2 CaO produced from calcination of phosphogypsum with sulfur as fuel can be used to produce low-CO.sub.2 clinker that replaces the use of high-CO.sub.2 limestone as raw material; (3) the use of sulfur as fuel to calcine phosphogypsum allows the production of low-cost sulfuric acid.

A system for making oxide material may comprise a preheating cyclone stage for receiving a solid carbonate material and operating at a temperature less than a calcination temperature of the solid carbonate material, a calcination cyclone stage for heating the preheated solid carbonate material and operating at a temperature of at least the calcination temperature to convert the preheated solid carbonate material to a solid oxide material and carbon dioxide gas, a cooling cyclone stage for cooling the solid oxide material and operating at a temperature less than the calcination temperature to cool the solid oxide material to ambient temperature, a first recirculating system to extract and recirculate a first gas from an outlet of the calcination cyclone stage to an inlet of the calcination cyclone stage zone, and a second recirculating system to extract and recirculate a second gas from the cooling cyclone stage to the preheating cyclone stage.

A process and device for enhancing the chemical protection capability of a collective protection filter whereby the process stream exiting the collective protection filter is passed through an Auxiliary Filter. The auxiliary filter containing an ammonia removal media, such as zirconium hydroxide impregnated with zinc chloride (ZnCl.sub.2/Zr(OH).sub.4), an oxidizing media, preferably zirconium hydroxide impregnated with potassium permanganate (KMnO.sub.4/Zr(OH).sub.4), and a methyl bromide removal media, preferably activated carbon impregnated with triethylenediamine (TEDA/carbon). The auxiliary filter and process are configured to remove toxic industrial chemicals including NH.sub.3, NO.sub.x (mixtures of NO and NO.sub.2) and CH.sub.2O, and CH.sub.3Br.

Methods and systems for producing aromatics and light olefins from a mixed plastics stream are described. The method may include feeding a plastic feedstock to a dechlorination operation to melt the plastic feedstock to release HCl and generate a liquid plastic stream; feeding the liquid plastic stream to a pyrolysis reactor, the pyrolysis reactor to generate hydrocarbon vapors; feeding the hydrocarbon vapors to an acid gas removal reactor with a solid inorganic alkali salt disposed within the reaction vessel to remove residual HCl and sulfur-containing compounds from the hydrocarbon vapors to generate a plastic derived oil; and feeding the plastic derived oil to a fluid catalytic cracking reactor to generate a product stream comprising light olefins having a carbon number of C.sub.2-C.sub.4 and aromatics. The associated system for processing mixed plastics into aromatics and light olefins is also described.

The methods and embodiments described herein involve installation of a gas sparging manifold into crude oil storage tanks, which facilitates removal of hydrogen sulfide (H.sub.2S) from bulk crude oil. Hydrogen sulfide stripped from the crude oil is scavenged via a forced-draft scavenging gas into a scavenging duct, and passes through an in-line filter. An alternative embodiment can be adapted for mobile use in a tank trailer/tank car capable of being towed by a tractor truck or locomotive.

The methods and embodiments described herein involve installation of a gas sparging manifold into crude oil storage tanks, which facilitates removal of hydrogen sulfide (H.sub.2S) from bulk crude oil. Hydrogen sulfide stripped from the crude oil is scavenged via a forced-draft scavenging gas into a scavenging duct, and passes through an in-line filter. An alternative embodiment can be adapted for mobile use in a tank trailer/tank car capable of being towed by a tractor truck or locomotive.

Disclosed is an adsorbent containing a metal oxide for adsorption of hydrogen sulfide in biogas, and a biogas purification system using the same.

A method for recycling CO.sub.2 from CO.sub.2 containing inputs to produce hydrocarbon products includes the steps of (i) capturing CO.sub.2 from at least one CO.sub.2 containing input, at least one of the at least one CO.sub.2 containing input including air; (ii) producing a CO.sub.2 feed stream from the captured CO.sub.2; (iii) reacting the CO.sub.2 feed stream with a H.sub.2 feed stream to produce a methane containing output; and (iv) separating the methane containing output so as to at least provide methane and a first waste output, wherein the first waste output is incinerated or gasified to provide one of the at least one CO.sub.2 containing inputs for step (i).

Capturing mercury or arsenic heavy metal from a moist gas containing water vapour, by: a) cooling the moist gas by heat exchange with a heat transfer fluid produced in e) in order to obtain a gas cooled to a temperature Tf, vaporizing the heat transfer fluid; b) separating condensed water and condensates contained in the cooled gas obtained in a) obtaining a gas depleted in water and a liquid stream containing water; c) compressing vaporized heat transfer fluid obtained from a) obtaining compressed heat transfer fluid; d) heating water-depleted gas by heat exchange with compressed heat transfer fluid obtained in c) obtaining a cooled heat transfer fluid and a gas reheated to a temperature Tc; e) decompressing cooled heat transfer fluid obtained in d), recycling heat transfer fluid to a); f) contacting reheated gas obtained in d) with a capture mass for said heavy metal.

Methods of sequestering carbon dioxide (CO.sub.2) are provided. Aspects of the methods include contacting an aqueous capture ammonia with a gaseous source of CO.sub.2 under conditions sufficient to produce an aqueous ammonium carbonate. The aqueous ammonium carbonate is then combined with a cation source under conditions sufficient to produce a solid CO.sub.2 sequestering carbonate and an aqueous ammonium salt. The aqueous capture ammonia is then regenerated from the from the aqueous ammonium salt. Also provided are systems configured for carrying out the methods.