Design, Supply, Start-Up and Operation of an Industrial Wastewater Treatment Plant, at a Petrochemical Complex in Lake Charles, Louisiana, USA

This petrochemical plant produces a broad portfolio of commodity chemicals globally, with three key divisions: Polymers, Solvents, and Explosives & Fertilizers (E&F). Their products are used in countless applications in our daily lives to add value, security and comfort. Typical applications include aerosols, cosmetics, fragrances, packaging, paints, adhesives, pharmaceuticals, polishes, printing and plastics and mining, pulp and paper, steel, textiles, water treatment and purification, agricultural fertilizers and chemicals. In 2014 the company approved the investment at The Lake Charles Complex, in Lake Charles Louisiana, USA which would roughly triple the company’s chemical production capacity in the country. Lake Charles Complex is located by the Gulf of Mexico in Louisiana and the facility extends over 400 acres. In addition to the seven manufacturing units, the complex also houses an R&D Laboratory. With plans to expand the site up to four times the capacity by 2020, the Lake Charles Complex will have a capacity of producing 1.5 million tons of ethylene annually. To support plant operations, SUEZ Water Technologies and Solutions designed and supplied four water treatment systems: • Raw Water Treatment - Sabine River canal water treated to reduce TSS and TOC • Demineralized Water - Make up high purity water for plant steam system and other users • Condensate Polishing - Treats return steam condensate for use as boiler feed water • Wastewater Treatment - Combined wastewater streams from the chemical plant The wastewater treatment system combines multiple streams from the plant and has a total flow rate of up to 1,200 gpm. Chemical products are added in different sections of the WWTP and coagulant and flocculant are added to the influent prior entering the DNF units. The wastewater treatment system consists of the following processes: The Dissolved Nitrogen Flotation (DNF) units are the first treatment stage that is used for oil and grease removal prior to the biological treatment line. Space for Nutshell Filters were incorporated to the design, but so far have not been installed. The biological treatment stage is composed of a Membrane Bioreactor using hollow fiber ultrafiltration (UF) membranes, which combines biological treatment by suspended growth activated sludge and the UF membranes that provides an absolute barrier for suspended solids. The MBR sludge is thickened in a biological sludge thickener prior to dewatering in the belt filter press. The belt filter press dewaters the sludge with the addition of polymer and hauled off site. Oil and grease from the DNF are sent to the Corrugated Plate Interceptor (CPI), the oil is recovered and sent back to the facility and the sludge from the CPI is dewatered in the plate filter press and hauled off site.