A Sustainable Solution for CTX Wastewater Treatment

The coal-to-chemicals (CTX) and coal-to-olefins (CTO) processes are highly water intensive, and the resulting wastewater is particularly toxic and difficult to clean. In China alone, the water footprint from existing and planned CTX facilities is projected to reach more than 3 billion cubic meters of water per year, and many of these facilities are located in areas that are already struggling to meet demands for water.

If all of this toxic wastewater was discharged into local waterways, it would be a public health and ecological disaster, which is why CTX wastewater is required to undergo zero liquid discharge (ZLD) treatment processes so that none of this wastewater is dumped into local waterways. This vital process turns this toxic wastewater into clean water and plays a crucial role in ensuring environmental sustainability, protecting human health, and promoting responsible industrial practices. Treating wastewater also allows it to be reused within the process, alleviating the demand on the local water supply. However, it can be an energy intensive process and create an additional cost burden on manufacturers.

Reverse osmosis (RO) membrane technology, in conjunction with energy recovery devices (ERDs), can vastly reduce the energy consumption and costs required to reach ZLD.

• Energy Efficiency: Membrane-based wastewater treatment is far more energy efficient than traditional thermal processes, particularly when paired with Energy Recovery devices such as the PX Pressure Exchanger resulting in significant OPEX savings.
• Reduced Footprint: Membrane systems are more compact and more flexible to design and install than traditional thermal systems.
• Circular Economy: Some valuable heavy metals, such as nickel, can be recovered from the wastewater and used in other industrial processes, helping to offset some treatment costs.

Performance, Reliability, and Design Simplicity

Our line of energy recovery devices can significantly compound the benefits of RO at a wide range of pressures. Our core PX® Pressure Exchanger®, its ultra high-pressure counterparts the PX U Series, and low pressure PXs work by harnessing pressure as the brine leaves the system and recirculating the energy, maximizing system efficiency. Systems using the PX are able to reduce energy consumption by as much as 60%, and significantly reduce the size of other system components.

Energy Recovery’s line of low, high, and ultra high-pressure solutions, as well as our Turbochargers and pumps, can dramatically reduce the energy costs, energy consumption, and emissions of membrane-based systems, delivering significant OPEX savings as well as CAPEX savings by minimizing the need for other system components. Our devices cover a wide range of pressures and flow rates to accommodate any size plant and have successfully been used in CTX and steel facilities to deliver significant energy and cost savings.

The PX has a simple design with just one moving part and no controls or electronics to boost reliability, making them easy to install and scale. They require no scheduled maintenance to maximize facility uptime and are effective under a wide range of operating conditions, providing efficiency and savings even as flow rate, pressure, or salinity levels change.