Wastewater micro discharge reuse equipment

Wastewater micro discharge reuse equipment：

Key considerations and equipment selection points:

1. Water quality and quantity: Accurate analysis of phosphorus forms (orthophosphate, hypophosphite, organic phosphorus?), fluoride concentrationpHCoexisting ions（Ca²⁺, Mg²⁺, Al³⁺, Fe³⁺, SO₄²⁻, ClThe content of organic matter, water content, and fluctuations. This is the basis for selecting the process and equipment scale.

2. Emission standards: Strictly define the emission limits for fluoride and total phosphorus that need to be met, as well as other indicators（COD, SS, pHEtc.).

3. Core process selection:

Calcium salt precipitation method (stone ash method): commonly used, low cost, can simultaneously remove phosphorus and fluorine. But the sludge production is large,pHHigh control requirements may result inCaSOThe precipitation effect is affected by factors such as ₄.

aluminum salt/Iron salt precipitation method: high phosphorus removal efficiency, good floc settling properties, and goodpHThe adaptability range is relatively wide. It has a certain removal effect on fluoride, but not as good as calcium salts. Iron salts may introduce chromaticity.

Combination process: such as "calcium salt defluorination+aluminium/Iron salt phosphorus removal "or" chemical precipitation+adsorption/Membrane treatment "to meet stricter standards.

4. Automated control:

Key:pHOnline monitoring and controlORP(oxidation-reduction potential, such as when treating secondary phosphorus), automatic control of chemical dosage (based on flow ratepHFluorine/Phosphorus online monitoring instrument feedback, liquid level control, equipment linkage. High level automation is the key to ensuring stable and compliant processing results, reducing operating costs, and minimizing manual intervention.

5. Equipment material:

Corrosion prevention is crucial: wastewater usually contains acid, alkali, fluoride ions (highly corrosive), and salt. Common materials:PP/PE/PVC/FRP(Pipeline, tank, agitator)316LStainless steel (key components), carbon steel lining rubber/plastic-lined/Apply epoxy. Avoid using ordinary carbon steel and glass.

6. Operating costs: Pharmaceutical expenses (lime, calcium salts, aluminum)/Iron saltPAMAcid and alkali), electricity (mixing, pumping, fan, dewatering machine), sludge disposal fee (high cost of hazardous waste disposal), labor cost, maintenance fee. Comprehensive consideration should be given to equipment selection and process optimization.

7. Floor area: Choose the appropriate equipment combination based on site conditions (such as efficient sedimentation tanks that save land compared to traditional sedimentation tanks).

Wastewater micro discharge reuse equipmentCore process and equipment composition

1. Quality pre-processing unit

-Nickel containing wastewater treatment:

-Equipment: Homogenization tank (corrosion-resistant steel mixing)+Fiberglass lined concrete pool（pHcontroller+NaOHDosing system, flocculation tank（PAMDosing), nickel precipitation tank.

-Function: Through chemical precipitation（pH 9~10）Generate nickel hydroxide sludge to ensure nickel meets the standard (≤)0.05 mg/L）.

-oily/Acid alkali wastewater treatment:

-Equipment: oil separation tank (density separation), regulating tank (water quality balance).

-Function: Remove floating oil and suspended solids, and reduce subsequent loads.

-Phosphorus containing wastewater treatment:

-Equipment: Dedicated coagulation tank (adding calcium salt or aluminum salt)+Design a sedimentation tank based on the characteristics of chemical polishing wastewater.

2. Deep processing and reuse unit

-Membrane separation system:

-Ultrafiltration（UF）：PPMaterial: Hollow fiber membrane（0.1 MmPrecision), removing colloids and emulsified oil.

-Reverse osmosis（RO）: Two levelsROSystem (such as8040Type membrane module), desalination rate>95%, achieve70%Reclaimed water (conductivity ≤)30 MS/cm）.

-Biochemical treatment:

-Biological Contact Oxidation Tank: Push Flow Design+Elastic three-dimensional filler, resistant to impact loads,CODHigh removal rate and low sludge production（90Tianpai Mud1Next time).

3. End of pipe guarantee and sludge treatment

-air flotation+Sand filtration: Remove residual suspended solids to ensure compliance with emission standards.

-Sludge dewatering: Plate and frame filter press (moisture content of sludge cake)<60%）Or centrifuge, nickel containing sludge classified as hazardous waste（HW32）Disposal.

Equipment characteristics and selection points

1. Integrated design

-Underground structure: saves surface space, can be covered with greenery, has good insulation, and is suitable for low-temperature environments.

-Fully automatic control:PLCReal time monitoring of the systempHAdd medication, membrane pressure difference, and reduce manual intervention for fault alarms.

3. Cost and Maintenance

-Investment: Membrane system accounts for a high proportion (approximately)40%）However, reusing profits can shorten the return period.

-Operation and maintenance:UF/RORegular chemical cleaning is required, and the filling material should be cleaned regularly5Annual replacement, medication（NaOHThePACThePAM）Proportion of operating costs60%

Summary: Equipment selection suggestions

-high-nickel/High phosphorus wastewater: choose 'chemical precipitation'+Membrane concentration "combination (such as Kangzheng)DF-ROProcess) to ensure compliance with heavy metal standards.

-highCOD/Oil wastewater: biological contact oxidation+Prioritize air flotation to reduce organic load.

-Emission demand:MVREvaporation realizes the resource utilization of salt crystallization.

Sludge treatment and resource recovery

Sludge classification: Cyanide containing sludge, chromium containing sludge, nickel containing sludge, etc. need to be classified and collected, and treated as hazardous waste by qualified units.

recycling:

Nickel containing sludge can be recovered by pyrometallurgy to recover metallic nickel;

Chromium containing sludge can be used to prepare chromium iron alloys or as a glass coloring agent;

Gypsum produced from acidic wastewater treatment（CaSO4）Can be used in the building materials industry.

Emission standards: Implement the "Emission Standards for Electroplating Pollutants"（GB 21900-2008）Key indicators:

totalhexavalent chromium≤0.5mg/LTotal nickel≤0.5mg/L(Direct emissions);

If discharged into a sewage treatment plant, it is necessary to negotiate with the receiving party to determine the pre-treatment standards.

Online monitoring: installationpHHeavy metals（Cr⁶⁺TheNi²⁺Online monitoring device, real-time monitoring of water quality.