1.1 Project Overview
Drilling wastewater generation 610,000 tons/Years, approx.8 ton/h, which contains various salts, chemicals and petroleum residues.
1.2 Water quality analysis
The main characteristic pollutants of the drilling wastewater provided by the owner are: oil,TDS, chlorides, etc. Due to the chlorides and TDS concentration up to 200000mg/L and 267588mg/L, biochemical treatment is no longer applicable. Therefore, the wastewater should be treated by physical and chemical methods. For characteristic pollutants such as oil and total organic carbon, targeted physical and chemical treatment methods should be used for pretreatment.
1.3Treatment process selection
According to the above analysis, the pollutants are TDS. The salt content of the chlorine and chloride is very high. Therefore, the evaporation process is the most feasible way. Considering that the project site may not have steam or natural gas supporting facilities, evaporation is considered to be MVR. It has certain advantages in terms of operating costs, operating stability and ease of operation and maintenance.
For oil substances, conventional oil separation and flotation processes are used for treatment. The dissolved air flotation equipment consists of flotation tank, dissolved air system, dissolved air return pipeline, dissolved air water release device, scraper device and electric control cabinet.
1.4 Solution design:Process flow chart
1.5Main structures and equipment
*1Main buildings: Original water pool, intermediate water pool and auxiliary rooms
*Main Equipment：Lifting pump, flotation device, stirring fan, lifting pump, evaporation equipment, electrical automatic control and instrumentation, cable tray, pipeline valve
