Enhancing recovery of magnesium as struvite from landfill leachate by pretreatment of calcium with simultaneous reduction of liquid volume via forward osmosis.

Title Enhancing recovery of magnesium as struvite from landfill leachate by pretreatment of calcium with simultaneous reduction of liquid volume via forward osmosis.
Authors S. Wu; S. Zou; G. Liang; G. Qian; Z. He
Journal Sci Total Environ
DOI 10.1016/j.scitotenv.2017.08.038
Abstract

Landfill leachate contains substances that can be potentially recovered as valuable resources. In this study, magnesium in a landfill leachate was recovered as struvite with calcium pretreatment; meanwhile, the leachate volume was reduced by using a submerged forward osmosis (FO) process, thereby enabling significant reduction of further treatment footprint and cost. Without pretreatment, calcium exhibited strong competition for phosphate with magnesium. The pretreatment with a Ca(2+): CO3(2-) molar ratio of 1:1.4 achieved a relatively low loss rate of Mg(2+) (24.1±2.0%) and high Ca(2+) removal efficiency (89.5±1.7%). During struvite recovery, 98.6±0.1% of magnesium could be recovered with a significantly lower residual PO4(3-)-P concentration (<25mgL(-1)) under the condition of (Mg+Caresidual): P molar ratio of 1:1.5 and pH9.5. The obtained struvite had a similar crystal structure and composition (19.3% Mg and 29.8% P) to that of standard struvite. The FO process successfully recovered water from the leachate and reduced its volume by 37%. The configuration of calcium pretreatment - FO - struvite recovery was found to be the optimal arrangement in terms of FO performance. These results have demonstrated the feasibility of magnesium recovery from landfill leachate and the importance of the calcium pretreatment, and will encourage further efforts to assess the value and purity of struvite for commercial use and to develop new methods for resource recovery from leachate.

Citation S. Wu; S. Zou; G. Liang; G. Qian; Z. He.Enhancing recovery of magnesium as struvite from landfill leachate by pretreatment of calcium with simultaneous reduction of liquid volume via forward osmosis.. Sci Total Environ. 2018;610-611:137146. doi:10.1016/j.scitotenv.2017.08.038

Related Elements

Magnesium

12 Mg 24.305000000 Magnesium

Magnesium Bohr ModelSee more Magnesium products. Magnesium (atomic symbol: Mg, atomic number: 12) is a Block S, Group 2, Period 3 element with an atomic mass of 24.3050. The number of electrons in each of Magnesium's shells is [2, 8, 2] and its electron configuration is [Ne] 3s2. The magnesium atom has a radius of 160 pm and a Van der Waals radius of 173 pm. Magnesium was discovered by Joseph Black in 1775 and first isolated by Sir Humphrey Davy in 1808. Magnesium is the eighth most abundant element in the earth's crust and the fourth most common element in the earth as a whole. Elemental MagnesiumIn its elemental form, magnesium has a shiny grey metallic appearance and is an extremely reactive. It is can be found in minerals such as brucite, carnallite, dolomite, magnesite, olivine and talc. Commercially, magnesium is primarily used in the creation of strong and lightweight aluminum-magnesium alloys, which have numerous advantages in industrial applications. The name "Magnesium" originates from a Greek district in Thessaly called Magnesia.

Calcium

20 Ca 40.078000000 Calcium

See more Calcium products. Calcium (atomic symbol: Ca, atomic number: 20) is a Block S, Group 2, Period 4 element with an atomic weight of 40.078. The number of electrons in each of Calcium's shells is [2, 8, 8, 2] and its electron configuration is [Ar]4s2. Calcium Bohr ModelThe calcium atom has a radius of 197 pm and a Van der Waals radius of 231 pm. Calcium was discovered and first isolated by Sir Humphrey Davy in 1808. It is the fifth most abundant element in the earth's crust and can be found in minerals such as dolomite, gypsum, plagioclases, amphiboles, pyroxenes and garnets. In its elemental form, calcium has a dull gray-silver appearance. Calcium is a reactive, soft metal that is a member of the alkaline earth elements. Elemental CalciumIt frequently serves as an alloying agent for other metals like aluminum and beryllium, and industrial materials like cement and mortar are composed of calcium compounds like calcium carbonate. It is also an biologically essential substance found in teeth, bones, and shells. The name "calcium" originates from the Latin word "calics," meaning lime.

Publish your research on the American Elements website