LPDC demoulding agent wastewater treatment, including pollution, demulsification, precipitation, reuse, and environmental compliance solutions

LPDC demoulding agent wastewater treatment, including pollution, demulsification, precipitation, reuse, and environmental compliance solutions
The wastewater from mold release agents contains organic silicon, emulsifiers, aluminum powder, and suspended aluminum slag, which directly discharge COD exceeding the standard. Many factories have environmental inspection checkpoints; Simple precipitation cannot break the emulsion, and the supernatant remains turbid and continues to exceed the standard.
1、 Wastewater pollutant indicators and control objectives
Main pollutants: organic silicon emulsifiers, suspended aluminum micro powders, oils and fats COD、SS； The COD of the original solution is generally 8000-20000mg/L.
Emission target after treatment: COD ≤ 500mg/L, SS ≤ 100mg/L; The recycling standards in the factory area are higher, COD≤200mg/L， Prevent the accumulation of silicon scale in the reuse pipeline.
Demulsifying agent: inorganic composite demulsifier is selected to break the silicone oil lotion and allow the silicone oil to agglomerate and float; Do not use a single PAC, as the demulsification may not be thorough.
PH control: pH 7.5-9.0 during the emulsion breaking stage; Low pH makes it difficult for silicone oil to become unstable; The pH is too high, causing aluminum ions to dissolve again.
A simple process plan for the treatment of mold release agent wastewater in Xinfeng Machinery is suitable for small and medium-sized casting workshops, reducing the amount of hazardous waste generated.
2、 Complete processing flow: water collection → demulsification → air flotation → sedimentation → filtration → reuse/discharge
1. Collecting tank: Collecting wastewater from mold spraying and washing, separating slag, and first settling large particle aluminum slag;
2. Reaction tank: adjust pH, add demulsifier and flocculant, stir to break the emulsion, and the silicone oil flocs float up;
3. Air flotation tank: Scrape off the upper layer of silicone oil scum (which belongs to hazardous waste);
4. Sedimentation tank: Sedimentation of aluminum micro powder sludge;
5. Quartz sand+activated carbon filtration, effluent detection; After passing the inspection, it can be reused or discharged through pipes.
Sludge and floating slag are packaged separately, while silicone oil floating slag is classified as hazardous waste and cannot be mixed with ordinary aluminum slag.
3、 Differences in wastewater control among overseas clients
Southeast Asia has a relaxed environmental protection policy, with most simply settling and discharging without deep treatment.
Online COD monitoring of North American factory wastewater, with priority given to using low COD biodegradable release agents and a complete hazardous waste ledger.
European foundries prioritize closed-loop reuse, wastewater is not discharged, emission taxes are reduced, and silicon free mold release agents are used to reduce treatment difficulty.
In the water scarce regions of the Middle East, mandatory wastewater reuse is required, with high treatment standards and supporting reverse osmosis deep filtration.
4、 Failure chain of wastewater treatment
Only PAC flocculation does not break the emulsion → Silicone oil maintains an emulsified state, COD remains high, and the supernatant is milky white;
PH not in the range of 7.5-9 → Failure of silicone oil destabilization and inability to remove floating oil through air flotation;
Mixing of floating slag and aluminum slag → all accounted for as hazardous waste, doubling the cost of hazardous waste;
The COD of the recycled liquid exceeds the standard → Silicon scale forms on the pipeline and mold spraying nozzle, blocking the atomizing nozzle.
5、 Long tail traffic layout ideas
Low pressure casting release agent wastewater treatment, silicone oil wastewater demulsification, and casting wastewater reuse, aimed at environmental protection and workshop supervisors.
keywords LPDC release agent wastewater treatment、silicone emulsion wastewater demulsification；
Problem class: COD control for aluminum casting release agent sewage;
Comparison category: silicone release agent vs silicone free release agent wastewater.
Suitable for workshop environmental protection and compliance management special pages.
6、 Common misconceptions in the industry
Misconception 1: Precipitation can treat mold release agent wastewater. Silicone oil is in an emulsified state, and simple precipitation cannot separate it.
Misconception 2: Scum and aluminum slag are both aluminum slag and can be mixed together. Silicone oil scum is a hazardous waste and should be disposed of as hazardous waste when mixed together.
Misconception 3: The treated wastewater is directly sprayed back into the mold, and high COD will clog the nozzle. It is necessary to filter and control COD.
FAQ
Q: Core pollutants in mold release agent wastewater?
A: Emulsified organic silicon, aluminum micro powder, high COD.
Q: What is the recommended pH range for demulsification?
A：7.5–9.0。
Q: What is the COD range of the original solution?
A：8000–20000mg/L。
Q: What are the properties of silicone oil scum?
A: Belonging to hazardous waste, collected separately.
Q: The core purpose of demulsification?
A: Breaking lotion, silicone oil agglomerates, floats and separates.
Q: Reuse additional filtering?
A: Sand filtration+activated carbon filtration.
Q: What is the reason for nozzle blockage?
A: Silicon scale and COD in recycled water exceed the standard.
Q: Low COD alternative solution?
A: Silicon free mold release agent.