Chemical Engineering MagazineChementator Briefs
Bio-isoprene Yokohama Rubber Co. (Tokyo, Japan; has developed what…
Chemical Engineering MagazineCO2-to-methanol
Researchers from Penn State University (State College, Pa.; and…


New phosphoric acid process expands available resources

By Mary Page Bailey |

Almost all phosphoric acid is produced via the wet-acid process (WAP), which requires relatively pure raw materials and produces large volumes of a potentially hazardous, special waste called phosphogypsum, which is highly regulated in terms of storage and disposal. A typical WAP operation will produce around 5 tons of phosphogypsum per ton of phosphate in phosphoric acid.

JDCPhosphate Inc. (Fort Meade, Fla.; has demonstrated its Improved Hard Process (IHP) for producing high-quality phosphoric acid, which not only avoids the production of phosphogypsum, but also enables the use of much lower-grade ores (13–14% phosphate content versus the 28% or more required for WAP). “The wet-acid process simply doesn’t work that well if the impurities in the phosphate rock are too high, things like iron, magnesium, aluminum and so on,” explains Timothy Cotton, CEO of JDCPhosphate. Furthermore, phosphoric acid produced via WAP requires various levels of upgrading, depending on the end use. “We can use more of the phosphate rock than the wet-acid process allows. We can’t overstate how important it is for the phosphate industry to widen the parameters of acceptable phosphate rock from what is currently used in the wet-acid process,” he adds.

IHP is a kiln-based process where raw materials are ground, mixed and agglomerated into feed balls with petroleum coke and clay, similar to iron-ore processing. The balls are then run through a rotary kiln, where a series of reduction and oxidation reactions pull elemental phosphorus out of the balls, converting it to phosphate. The phosphate is then captured in a hydration unit where it is absorbed into water, resulting in high-quality phosphoric acid. Once the phosphate content is removed, the processed balls are a co-product (mostly hard calcium silicate) that can be used as a construction aggregate. JDCPhosphate runs a demonstration plant that can process about 100 kg/h of feed. Recently, the company successfully produced high-quality phosphoric acid from a low-grade ore that contained just 14% phosphate and included high levels of impurities like silica and magnesium oxide. The company plans to continue upgrading this facility to validate an even wider range of phosphate ores and further scale up the operation.



Related Content
Making multifunctional windows
Concern with energy efficiency has increased the popularity of window glass coatings that control the amount of sunlight that passes…
Researchers from Penn State University (State College, Pa.; and Dalian University of Technology (Dalian, China; have improved the…

Chemical Engineering publishes FREE eletters that bring our original content to our readers in an easily accessible email format about once a week.
Subscribe Now
Simplify sensor handling and maintenance with ISM
Three reasons to measure pH in-line
ABB Ability™ technology to transform BASF rotating equipment into intelligent machinery and improve uptime and reliability
Detect and correct anomalies early in your batch processes
ABB at ACHEMA 2018

View More

Live chat by BoldChat