TOKYO -- Worldwide demand for phosphorus is growing despite its limited supply, so Japanese companies such as Hitachi Zosen, are finding ways to recycle the valuable commodity from sewage and animal droppings for reuse in fertilizers and lithium-ion batteries, among other applications.

Phosphorus is used to make lithium-ion batteries used in many electronics such as cell phones and cars.

     Given that phosphorus reserves are only found in several countries, efficient recycling methods could create a stable supply of the resource.

     Hitachi Zosen has created a way to recover phosphorus from swine manure more efficiently than before. The recovery system is capable of removing 600 tons of phosphorus annually from 14,000 tons of pig manure, according to the company. The manufacturer hopes to sell the technology to agricultural and livestock producers at a cost of at least 500 million yen ($4.08 million) per unit. The company has set an annual sales target of 3 billion yen. It plans to start marketing the system in fiscal 2015.

     Approximately half of the 3.7 million tons of pig manure generated annually across Japan has been used almost free of charge by farmers to fertilize their fields, with the remainder being treated as industrial waste. If the compost can be recycled effectively, this could make possible the recovery of roughly 80,000 tons of phosphorus from the waste. This approach will provide a new source of income for agricultural and livestock farmers.

     Swing, a Japanese water consultancy and provider of related equipment, will begin selling phosphorus retrieved from sewage. The company, jointly invested by Mitsubishi, Ebara and JGC, plans to launch phosphorus recycling activities as early as fiscal 2015, which ends in March 2016.

     Swing, in collaboration with Kobe's city government, tested phosphorus recovery methods on sewage sludge, and manged to create a new way to remove impurities from wastewater. Improving phosphorus recovery efficiency is likely to keep the cost of the material at almost the same level as import prices of the expensive commodity. The company aims to sell fertilizers containing phosphorus to farmers and other buyers.

     Because phosphorus can crystallize in wastewater, clogging pipes, its removal also reduces maintenance costs for sewage infrastructure. Metawater, an environmental water engineering company, also offers a system for recovering phosphorus from sewage.

     Phosphorus is mainly used in fertilizers and as a material for lithium-ion batteries. Japan relies almost entirely on imports from countries such as China and Jordan for supplies of the substance. The price of phosphorus rock has jumped dramatically to slightly over 24,000 yen per ton from around 10,000 yen in the early 2000s due to growing demand for phosphorus fertilizers used to enhance food production and because of export restrictions by some countries.   

(Nikkei)