Water treatment developer Aquatech has been awarded a contract to provide a water treatment facility that includes a zero liquid discharge (ZLD) plant for a coal-to-liquid-fuels conversion project being developed by Shenhua Ningxia Coal Industry, a division of Shenhua Group, China’s biggest coal producer.
The ZLD plant will recycle more than 55 million liters per day (2,300 cubic meters per hour) of wastewater generated by the 4 million tons per year CTL plant and eliminate all wastewater discharge. The recycled water will be treated to a high purity level and reused in the process facility.
Shenhua selected Aquatech to design, engineer, and supply the integrated water facility, and to supervise installation and commissioning.
Aquatech will supply a fully integrated and automated system that it has developed for the CTX market. This system utilizes AquaEZ technology consisting of conventional UFRO, HERO (High Efficiency Reverse Osmosis), Unseeded Falling Film evaporators, followed by crystallizers at the back end to achieve compete zero liquid discharge.
Aquatech will also supply the post-treatment of the recycled water with an ion exchange process to give high purity water to be used back in the process.
The project will ensure that Shenhua Ningxia complies with statutory regulations and minimizes its overall water footprint, an important consideration since coal conversion requires substantial amounts of water — as much as 10 tons of fresh water for 1 ton of coal-derived fuel according to some estimates.
The project is located in northwest China, a dry, water-stressed region.
Last month Aquatech introduced the AquaR2RO membrane process designed for use in facilities requiring ZLD or very high recovery.
The process is designed for industries such as oil and gas, power generation, steel, pulp and paper, and where the feed water has high scaling / fouling potential. Aquatech says in some applications, AquaR2RO can achieve more than 98 percent recovery.