Project Overview:

In July 2012, Botian Environment signed a contract with Pucheng Clean Energy Chemical Co., Ltd. to undertake the wastewater treatment unit, reuse water unit, and demineralized water unit for the company's 1.8 million tons/year methanol and 700,000 tons/year olefins project. All units have now been completed and commissioned. The project is located in Pucheng County, Weinan City, Shaanxi Province, and adopts Texaco gasifier and Dalian Institute of Chemical Physics' DMTO second-generation olefins-from-methanol technology. Therefore, the wastewater mainly comes from gasification wastewater and DMTO unit drainage, characterized by high ammonia nitrogen and high hardness. Leveraging our company's accumulated experience in the coal chemical industry, we adopted an economical and reasonable process route and secured this largest water treatment EPC contract in the new coal chemical field.

Process Overview:

Wastewater: Regulation + Coagulation + Sedimentation + SBR

Reuse Water: BAF + Clarification + Active Sand Filter + Dual-Membrane System + Concentrate RO

Concentrate Treatment System: Heterogeneous Catalytic Oxidation

Demineralized Water: UF + Two-Stage RO + Mixed Bed

Process Condensate: Filtration + Cation Bed + Mixed Bed

Turbine Condensate: Filtration + Mixed Bed

Project Scale:

Wastewater: 1300m³/h

Reuse Water: 2400m³/h

Concentrate Treatment System: 600m³/h

Demineralized Water: Primary Demineralized Water 1600m³/h

Process Condensate: 600m³/h

Turbine Condensate: 1200m³/h

Project Highlights:

The wastewater system combines multi-stage series technology with SBR process, dividing the SBR reaction into multiple alternating anoxic and aerobic stages over time. This environment restricts filamentous bacteria-induced sludge bulking, improving sludge settling rate. At the same time, the duration of each separated reaction stage matches microbial activity, fully utilizing the rapid denitrification phase, creating a favorable biological environment, promoting complete nitrification and denitrification reactions, enhancing organic removal efficiency, and achieving compliant treatment of high-ammonia-nitrogen wastewater pollutants.

The concentrate is treated with heterogeneous catalytic oxidation technology. The high-activity heterogeneous catalytic filler reacts with Fe³⁺ generated from the reaction to form FeOOH heterogeneous crystals, catalyzing the generation of more hydroxyl radicals with extremely strong oxidation capability, reducing chemical dosing and sludge production.