How do large domestic environmental protection companies treat coal chemical wastewater?

Most of the coal chemical industries that have emerged in my country in recent years are located in the northwest region, which has little water resources. The coal chemical industry is an industry that consumes a lot of water resources and produces wastewater. Therefore, wastewater

The following will share with you Shenhua Baotou coal-to-olefins, Shenhua Ordos coal direct liquefaction, and Shaanxi Coal Chemical Group Pucheng

Project name: Overall coal chemical water system of Yuntianhua Group Hulunbuir Jinxin Chemical Co., Ltd. Solution

Keywords: Model of overall water system solution in the coal chemical industry

Project Introduction

Hulunbuir Jinxin Chemical Co., Ltd. is a subsidiary of Yuntianhua Group . The project is located deep in the Hulunbuir prairie, and the local government requires that the environmental protection facilities of such chemical projects must reach "zero emission" levels. At the same time, this project is the first in Asia to use BGL furnace (British Gas-Lurgi British Gas-Lurgi furnace) coal-to-gas production to produce synthetic ammonia and urea. The wastewater generated during the production process has complex composition, high pollution level, and difficult treatment. This project has also become a model for overall water system solutions in the domestic coal chemical industry.

Project scale

Gas water: 80m3/h Wastewater: 100m3/h

Recycled water: 500m3/h Desalted water: 540m3/h

Condensate: 100m3/h

Main processes

Gas water: oil removal, hydrolysis, acidification, SBR, coagulation and precipitation, BAF, mechanical stirring, clarification tank, sand filtration

Sewage: air flotation A/O

Desalted water: raw water heat exchange UF RO mixed bed

Condensate water: heat exchange iron removal filter mixed bed

Back Water: clarifier, multi-media filtration, ultrafiltration, one-stage reverse osmosis, concentrated water reverse osmosis

Botian Environmental Group

Technical Highlights

1. Coal gasification wastewater contains A large amount of oil, with a content of up to 500mg/L, exists in the form of heavy oil, light oil, emulsified oil, etc. The project is equipped with oil separation and air flotation units to remove oil. The air flotation uses nano-bubble technology, and the diameter of nano-scale micro-bubbles is 30-500nm. , compared with traditional dissolved air flotation, the number of bubbles is larger, the residence time is longer, and the utilization rate of bubbles is significantly improved, thus greatly improving the oil removal effect and processing efficiency.

2. The characteristics of coal gasification wastewater are high COD, high phenol, high salt, low B/C ratio, and contain a large amount of refractory substances. It adopts hydrolysis and acidification process and does not produce methane. It uses the hydrolysis and acidification tank. Hydrolysis and acid-producing microorganisms treat sewage in the subsequent biochemical treatment unit with less energy consumption and a shorter residence time.

3. Gas wastewater contains high ammonia nitrogen. Setting up SBR can achieve the purpose of nitrogen and carbon removal at the same time.

4. The mature application of the double-membrane method in desalted water and recycled water treatment processes can effectively reduce acid and alkali consumption per ton of water and is easy to operate. After three years of operation, the current system's desalination rate can still reach 98%.

Project name: Water treatment device EPC project of Shaanxi Coal Chemical Group Pucheng Clean Energy Chemical Co., Ltd.

Keywords: Water treatment EPC project with the largest contract value in the new coal chemical industry

Project Introduction

This project is located in Pucheng County, Weinan City, Shaanxi Province. It uses Texaco gasifier and Dalian Institute of Chemical Physics' DMTO second-generation olefins to methanol technology. Therefore, the wastewater is mainly gasification wastewater and DMTO device drainage, which has the characteristics of high ammonia nitrogen and high hardness. Potian Environment undertook the sewage plant, recycled water plant and desalted water plant of the company's annual production of 1.8 million tons of methanol and 700,000 tons of olefins. The total water treatment EPC contract amount reached 509 million yuan.

Project scale

Sewage: 1300m3/h Recycled water: 2400m3/h

Concentrated water treatment system: 600m3/h

Desalination Water: primary desalted water 1600m3/h

Process condensate: 600m3/h Turbine condensate: 1200m3/h

Main process

Sewage: regulation Coagulation and sedimentation SBR

Recycled water: BAF clarification activated sand filter double membrane system concentrated water RO

Desalted water: UF two-stage RO mixed bed

Concentrated water Treatment system: heterogeneous catalytic oxidation

Process condensate: filtered positive bed mixed bed

Turbine condensate: filtered mixed bed

Technical highlights

1. The sewage system combines multi-stage series technology with the SBR process, dividing the SBR reaction process into multiple alternating anoxic and aerobic conversion stages in time. In this environment, the pollution caused by filamentous bacteria Mud expansion will be limited and the sludge settling rate will increase; at the same time, the length of each separated reaction section is consistent with the microbial activity, making full use of the rapid denitrification stage to create a good biological environment and promote the thorough nitrification and denitrification reactions. carry out to improve the removal efficiency of organic matter and achieve standard treatment of high ammonia nitrogen sewage pollutants.

2. The concentrated water adopts heterogeneous catalytic oxidation treatment technology. The highly active heterogeneous catalytic filler used reacts with Fe3 to form FeOOH heterogeneous crystals, which catalyzes the generation of more hydroxyl radicals and has extremely strong oxidation properties. ability to reduce the dosage of chemicals and the amount of sludge generated.