Shale Gas Wastewater Treatment Process - Effective Solutions for Shale Gas Wastewater
Shale gas extraction generates a significant amount of wastewater that contains complex contaminants, including high salinity, heavy metals, and organic compounds. Proper treatment of this wastewater is essential for environmental protection and sustainable resource management.
The treatment of shale gas fracturing flowback wastewater is a sophisticated and essential process designed to minimize environmental pollution, safeguard water resources, and enable the resourceful utilization of wastewater.
In the treatment process of shale gas fracturing flowback fluid, MVR evaporation technology plays a pivotal role. It works by introducing the wastewater into an evaporator, where heat energy is used to evaporate the water, effectively reducing the volume of wastewater. Simultaneously, during the evaporation process, salts in the wastewater crystallize, allowing for the separation and recovery of valuable components, thereby enabling resource utilization of the wastewater. WTEYA Group's advanced MVR evaporation technology not only ensures efficient wastewater treatment but also significantly reduces treatment costs, offering a sustainable and cost-effective solution.
Characteristics of Fracturing Flowback Wastewater
Shale gas fracturing flow back wastewater exhibits the following key characteristics:
High Salinity
Due to the dissolved minerals and salts carried from the geological formation, the wastewater contains a high concentration of salt substances.
High Organic Matter Content
It includes additives from fracturing fluids, such as thickeners, organic boron cross-linking agents, gel breakers, and natural organic matter present in the formation.
High Suspended Solids
Initially, the wastewater contains a significant amount of suspended solids, which gradually decreases as flowback progresses.
Presence of Heavy Metals and Radioactive Substances
In rare cases, the wastewater may also contain trace amounts of heavy metals and naturally occurring radioactive materials.
Treatment Process Flow
1. Pretreatment
Purpose: To remove large suspended particles, organic matter, and heavy metals from the wastewater.
Methods:
· Technologies such as cyclones, flotation, flocculation sedimentation, chemical softening, and filtration are employed.
· Specific techniques include electro-flocculation, composite alkali softening, and breakpoint methods to remove ammonia nitrogen.
2. Desalination Treatment
Purpose: To reduce salt content, ensuring wastewater meets subsequent treatment or discharge standards.
Methods:
· Processes like multi-effect evaporation desalination effectively remove salts and heavy metals, lowering conductivity and total dissolved solids (TDS).
3. Deep Treatment
Purpose: To further eliminate organic matter, heavy metals, and other pollutants.
Methods:
· Technologies such as activated carbon adsorption and membrane separation offer high efficiency, stability, and automation, enhancing the overall treatment effect.
4. Improve Resource Utilization
Purpose: To reduce treatment costs and convert wastewater into valuable resources.
Methods:
· Vacuum evaporation separates water, producing condensate that meets discharge standards.
· Crystallized salts extracted from wastewater can be repurposed as industrial salt for chemical production.
5. Final Treatment and Discharge
Purpose: To ensure treated wastewater complies with discharge standards or is suitable for reuse.
Methods:
· Comprehensive testing confirms compliance with Level I standards of the Comprehensive Sewage Discharge Standard.
· Additional stringent purification steps are applied in specific cases to meet higher requirements.
Technical Challenges and Solutions
Challenges:
· Complex Wastewater Composition: Varying contaminants make treatment difficult.
· High Treatment Costs: Energy-intensive processes increase operational expenses.
Solutions:
Developing Advanced Technologies:
Innovations in desalination and deep treatment processes improve efficiency and lower costs.
Focusing on Resource Utilization:
Extracting valuable materials like industrial salts reduces waste and enhances economic benefits.
External Discharge Treatment for Fracturing Flowback Wastewater
For standard external discharge, the treatment must remove SS (suspended solids), oil, COD (chemical oxygen demand), ammonia nitrogen, hardness, and TDS. A critical focus is on separating high TDS from water to meet stringent discharge standards.
Process Overview:
· Pre-treatment: Flotation, catalytic oxidation, and softening precipitation.
· Filtration: Ultrafiltration and concentration.
· Final Stages: Evaporation crystallization and deep treatment.
Resource Utilization:
NaCl is extracted as a by-product, usable as a chemical raw material or livestock salt.
Deep treatment equipment is tailored to water quality, ensuring compliance with discharge standards.
For instance, when using electrodialysis, additional COD removal systems are required. Similarly, if evaporation crystallization occurs under alkaline conditions, ammonia nitrogen removal systems are necessary for compliance.
Given the complexity and high standards of external discharge, centralized treatment facilities are recommended to optimize the process and manage return fluid effectively.
Why Choose WTEYA Group?
· Tailored Solutions: Every enterprise has unique needs. WTEYA Group specializes in providing customized water treatment solutions that consider wastewater type, treatment scale, and specific operational requirements.
· Proven Expertise: With rich industry experience, WTEYA Group ensures reliable and effective system design and implementation.
· Cutting-Edge Technology: Our MVR systems are designed for superior performance, helping you achieve zero discharge and meet environmental regulations.
Let WTEYA Group design an MVR evaporation system that is perfectly suited to your requirements. Contact us today for a detailed quotation:
· Email: info@wteya.com
· WhatsApp: +86-1800 2840 855
Get the right solution to turn your wastewater challenges into sustainable outcomes!