Characteristics：

1. Out of date pretreatment technologies have been used such as oil interceptor or DAF (dissolved air floatation), which effluent contains significant amount of oil more than 50 mg/L. Part of them is emulsified oil .

2. The major restriction for wastewater treatment in petroleum refinery is the poor performance of biological process. The key issues are: poor activated sludge and hardly degradable contaminates. 

3. Water reclamation, further polishing to reduce the hardly degradable contaminates have been paid more attentions: such as COD, total nitrogen and salt removal.


Problems of the wastewater treatment 

From too many different resources:

Include oily wastewater, salty wastewater, sulfur contaminated wastewater, initial rainwater, domestic sewage, process backwash water etc.

Hardly degradable contaminates:
Wastewater characteristics is strongly impacted by the resources of wastewater and different refinery processes. The major contaminates include: oil, phenols, sulphides and ammonia etc. With high content of COD, hardly degradable substances, and highly variable pH. The majority contaminates are hardly degradable organic materials, typically hydrocarbons and their derivatives.

High concentrations with highly variable:

Normally its BOD is within a range of 150 to 250 mg/L, COD is between 300 and 600 mg/L. Salty wastewater contains oil with a range of 100 to 300mg/L. The washing water from the oil tanker can be as high as 5000 mg/L oil. The range of benzene is between 1 and 100mg/L. Benzopyrene is less than 100mg/L. Chromium is in a range of 0.1 to 100mg/L, and lead is in a range of 0.2 to 10mg/L.

The wastewater treatment processes in petroleum refinery industrial

The wastewater treatment processes include: pretreatment, biological process and post-polishing (desalination and reuse).

Pretreatment: includes oil, SS removal and pH adjustment. It protects the downstream  processing.

Biological process: based on biological decomposition of organic contaminates such as COD, SS, N and P etc.

Post-polishing: To remove the residuals such as SS, COD and salts etc. It often uses DAF, ozone oxidation, filtrations: BAF, UF, RO, EDR, sand filter and other equipment.

The solution of Highnew 

Regards to technology

A. Apply typical lamella plate oil interceptor and followed a DAF to improve the pretreatment performance and achieve a residual oil in the effluent less than 10 ppm;

B. Optimize biological process. use a patent technology of combined multiple biological methods that are developed by Highnew;

C. Apply a patented DAF and filtration to polish the treated water and reclaim the effluent for reuse. 

Regards to management

A. Choose from multiple modes as EPC, BOT, BOO, trusteeing operation, TOT etc. to implement a professional management;

B. Focus on daily operation and maintenance. 

Regards to economic

A. Change mind, to be smart in capital investment and in operational cost saving;

B. Take the contaminates and water as resources, rather than a wastes. 


Highnew – preferred wastewater treatment processes

1. Powerful pretreatment process for oil removal

2. PACT enhanced biological process

3. New textile type of biological carrier for SAF

4. Mathematics modelling and simulating

5. MBR process

6. Highly efficient ammonia and nitrogen removal process

7. SODO process for upgrading

8. BAF used for effluent polishing

9. MF-RO effluent purify process

10. Zero discharge for salty wastewater process

Highnew - pretreatment

The oil interceptor is used to remove free oil from oily water. The oil content in its effluent is normally in a range of 50 to100 mg/L.

This pre-treatment relies on static settling, lamella plate and oil coagulant etc.

The unit can be used for gravity feed or pumped feed. It may require additional heating. flushing in case there is any blocking.

The pretreatment devices are:

Lamella plate oil interceptor used for oily wastewater treatment;

The pressured lamella plate vessel is normally used for offshore platform, which can be built in horizontal and vertical types.