Aquatech awarded contract to install wastewater recycle and zero liquid discharge system in China

“With this order intake, Aquatech is now well-equipped to offer optimized wastewater recycle and zero liquid discharge solutions not only to the emerging coal chemical market segment but also to other complex wastewater recycle and ZLD requirements in other industries in the Chinese market,” said Tom Tseng, General Manager, Aquatech (Guangzhou) Water Treatment Co. Ltd.

 

Ordos is in a locality in China where water scarcity is critical and the area is under the threat of desertification. Hence, the pollution control norms are very strict, and a zero liquid discharge (ZLD) facility in local projects is a mandatory requirement. The EPC contractor for the project, East China Engineering Science & Technology (ECEC), selected Aquatech to implement a wastewater recycle and ZLD system at the site.

 

Chinacoal Tuke fertilizer project (Phase I) is invested by Chinacoal Ordos Energy Chemicals Limited Company. Phase I will manufacture 1 million tons per year of synthetic ammonia and 1.75 million tons per year of urea. When the whole project is completed, it will produce 2 million tons of synthetic ammonia and 3.5 million tons of urea. This project uses the rich coal resources in the Ordos coal mines to realize local resource transformation with mature, advanced and reliable technology.

 

In this project, the coal chemical process uses broken coal slag pressurized gasification technology to make raw gas, which is converted to hydrogen production. After cooling, purification and removal of impurities such as sulfide, CO2 and methane, hydrogen will be compressed with nitrogen in a synthesis gas compressor. The final product, urea, will come out from the ammonia synthesis working section. The product is urea, and the byproducts are methane gas and oil, etc. This project includes a urea unit, ammonia synthesis unit, gasification unit, air separation unit and utilities.

 

As part of the water treatment system, Aquatech is supplying two units – a high efficiency reverse osmosis (HEROTM) unit and a ZLD unit. The reject water from the effluent treatment plant is fed to the HERO plant, which consists of a clarifier, followed by a dual media filter, a weak acid cation unit, and then a reverse osmosis (RO) unit. The reject from the RO is sent to a brine concentrator and then to an evaporation pond. The RO permeate and the distillate from the brine concentrator is collected in the RO permeate tank.

 

Aquatech will provide the concentrated brine treatment plant in the utilities unit. It will treat concentrated brine from the water reuse plant. The reuse water plant is for treating discharge from waste water treatment plant, reject/waste from the demineralization plant, and blow down from the circulating water station.

 

The wastewater treatment plant treats all the industrial waste from the fertilizer project. The wastes are mainly recycled wastewater from phenol ammonia, blow down from gasification circulating water, wash waste from low temperature methyl alcohol and other integrated wastewater (such as ground rinse water, sanitary wastewater). The main pollutants in wastewater are from phenol ammonia waste in the gasification process.

 

ECEC has evaluated various technologies available in the industry, and has selected this process offered by Aquatech in view of its proven record of higher recovery from wastewater systems and better life cycle costs. ECEC’s decision was also influenced by Aquatech’s installation in the YTH project in China, which has a similar scheme.