PPH pipe applications are mainly found in chemical wastewater treatment, acid and alkali drainage, electroplating wastewater1, acid pickling lines, scrubber systems and environmental protection equipment.
PPH pipe is suitable for many acid, alkali and salt solutions. It is widely used in welded plastic piping systems where good chemical resistance and reliable joint strength are required. However, PPH is not recommended for strong oxidizing acids2, aromatic hydrocarbons, some ketones, some esters and high-temperature solvent systems.
What is PPH pipe used for?
PPH pipe is used for acid and alkali wastewater, chemical drainage, scrubber circulation lines, electroplating wastewater and environmental protection equipment.
PPH industrial piping system installed in a chemical wastewater treatment plant.
| Application | Why PPH Is Used |
|---|---|
| Chemical wastewater treatment | Good resistance to many acid and alkali liquids |
| Electroplating wastewater | Suitable for acid and alkali discharge lines |
| Acid pickling lines | Suitable for many acid wastewater conditions |
| Alkali washing lines | Suitable for alkaline wastewater systems |
| Scrubber systems | Used for circulation and spray liquid lines |
| Acid mist purification towers | Suitable for many acidic circulation liquids |
| Environmental protection equipment | Welded piping provides good system integrity |
| Chemical tank connection lines | Suitable for many acid, alkali and salt solutions |
PPH is commonly used in welded piping systems for chemical wastewater, acid and alkali drainage, and scrubber circulation lines.
What chemicals can PPH pipe handle?
PPH pipe can handle many acid, alkali and salt solutions, especially in wastewater and environmental protection systems.
High-quality PPH pipes and fittings designed for excellent chemical resistance.
| Suitable Media | Typical Examples |
|---|---|
| Acid wastewater | Acid pickling wastewater, acidic industrial wastewater |
| Alkali wastewater | Alkaline cleaning wastewater, alkali washing liquid |
| Salt solutions | Sodium chloride solution, many inorganic salt solutions |
| Electroplating wastewater | Acid and alkali electroplating wastewater |
| Scrubber circulation liquid | Acid mist scrubber liquid, gas washing liquid |
| Common inorganic acids | Hydrochloric acid, low to medium concentration sulfuric acid, dilute nitric acid |
| Weak organic acid water solutions | Dilute acetic acid solution |
| Other water-based media | Carbonic acid solution, aluminum salt solution, ammonium salt solution, glycerin, glucose solution |
PPH is especially suitable for chemical wastewater systems where the medium is mainly water-based acid, alkali or salt solution.
What chemicals are not recommended for PPH pipe?
PPH pipe is not recommended for strong oxidizing acids, high-concentration nitric acid, high-temperature concentrated sulfuric acid, aromatic hydrocarbons, some halogenated hydrocarbons, some ketones and some esters.
| Not Recommended Media | Risk |
|---|---|
| High-concentration nitric acid | Strong oxidizing risk |
| High-temperature concentrated sulfuric acid | Oxidation and material degradation risk |
| Strong oxidizing mixed acids | Not recommended |
| Benzene | Aromatic hydrocarbon attack risk |
| Toluene | Not recommended for long-term use |
| Aromatic hydrocarbon solvents | May cause swelling or softening |
| Some halogenated hydrocarbons | Compatibility risk |
| Some ketone solvents | Not recommended without confirmation |
| Some ester solvents | Not recommended without confirmation |
| Strong solvent-based paints | Solvent attack risk |
| Long-term high-temperature oxidizing media | May reduce service life |
PPH is strong in many acid and alkali wastewater systems, but it should not be treated as a universal chemical pipe for all solvents and oxidizing media.
What standards are used for PPH pipe?
PPH pipe is commonly used in industrial and chemical piping systems, especially welded pipe systems.
PPH pipe jointing via hot-melt welding according to DVS guidelines.
| Application | Common Standards | Common Pressure Classes |
|---|---|---|
| Chemical piping | DIN 8077/8078, ISO 154943 | PN10, PN16 |
| Acid and alkali wastewater | DIN, ISO series | PN6, PN10 |
| Scrubber systems | DIN/ISO piping or project-specific design | Low-pressure circulation systems |
| Environmental equipment piping | DIN 8077/8078, ISO 15494 | PN6, PN10, PN16 |
| Welded plastic piping | DVS welding guidelines are commonly referenced | Based on system design |
PPH systems are often installed by hot-melt welding, socket welding or butt welding. The welding quality is important for long-term reliability.
What pressure ratings are available for PPH pipe?
Common PPH pipe pressure ratings include PN6, PN10 and PN16.
In environmental protection systems and scrubber circulation lines, the pressure is often not very high. PN6 or PN10 may be enough for many low-pressure circulation or drainage systems. For pressurized chemical liquid transfer, PN10 or PN16 may be required.
Pressure selection should consider:
- Chemical medium
- Working temperature
- Pipe diameter
- Welding method
- Pump pressure
- System layout
- Continuous operation time
- Safety factor
Like other plastic pipes, PPH pressure capacity decreases when temperature increases4.
How to select PPH pipe for different applications?
PPH pipe is suitable for acid and alkali wastewater, electroplating wastewater, scrubber systems and welded chemical drainage lines.
PPH piping used in gas scrubber and acid mist purification tower systems.
| Application Condition | PPH Selection Advice |
|---|---|
| Acid and alkali wastewater | PPH is often suitable |
| Electroplating wastewater discharge | PPH is commonly used |
| Scrubber circulation liquid | PPH is a common choice |
| Acid pickling wastewater | PPH may be suitable after checking concentration |
| Environmental equipment piping | PPH is often suitable because of welded joints |
| Strong oxidizing acid | PPH is not recommended |
| Aromatic hydrocarbon solvent | PPH is not recommended |
| High-purity chemical system | PVDF may be better |
| Standard water treatment | PVC or CPVC may be more economical |
PPH is widely used for acid and alkali wastewater.
For standard water treatment, PVC pipe may be more economical.
For higher temperature systems, CPVC pipe may be considered.
For high-purity or stronger chemical systems, PVDF pipe may provide better long-term stability.
Summary
PPH pipe is suitable for:
Acid wastewater, alkali wastewater, industrial wastewater, electroplating wastewater, acid pickling wastewater, alkali washing liquid, scrubber circulation liquid, salt solutions, acid-alkali neutralization liquid and chemical environmental protection systems.
PPH pipe is not recommended for:
High-concentration nitric acid, high-temperature concentrated sulfuric acid, strong oxidizing mixed acids, benzene, toluene, aromatic hydrocarbons, halogenated hydrocarbons, some ketones, some esters and strong solvent-based paints.
PPH is best positioned as a welded plastic pipe material for chemical wastewater, acid and alkali drainage, electroplating wastewater, scrubber systems and environmental protection equipment.
"Treatment of electroplating industry wastewater: a review ... - PubMed", https://pubmed.ncbi.nlm.nih.gov/35084684/. Polypropylene piping is used in electroplating wastewater systems due to its resistance to the acidic and alkaline solutions commonly present, though compatibility should be verified for specific metal salt concentrations and additives. Evidence role: case_reference; source type: research. Supports: the use of polypropylene materials in electroplating wastewater systems. Scope note: Electroplating wastewater composition varies significantly by process type and may contain chemicals requiring individual compatibility assessment ↩
"Polypropylene Chemical Compatibility Chart - CP Lab Safety", https://www.calpaclab.com/polypropylene-chemical-compatibility-chart/?srsltid=AfmBOop_eDO9pEDZsF6A_ycEdvOEiIBoPWQrMyq4mQcdZnPro4wB97JE. Polypropylene exhibits limited resistance to strong oxidizing acids such as concentrated nitric acid and hot concentrated sulfuric acid, which can cause oxidative degradation of the polymer chain. Evidence role: mechanism; source type: research. Supports: the degradation mechanism of polypropylene when exposed to strong oxidizing acids. Scope note: Degradation rates depend on acid concentration, temperature, and exposure duration ↩
"[PDF] Polypropylene Pipe Din8077 - extnag.tacc.utexas.edu", https://extnag.tacc.utexas.edu/fetch.php/s24ABL/243240/polypropylene_pipe__din8077.pdf. DIN 8077/8078 specifies requirements for polypropylene pipes and fittings for pressure applications, while ISO 15494 covers plastic piping systems for industrial applications. Evidence role: general_support; source type: institution. Supports: the applicability of these standards to polypropylene piping systems. Scope note: Standards may have specific scope limitations regarding material grades, applications, or geographic adoption ↩
"Temperature Dependence of Tensile Properties and Deformation ...", https://pubmed.ncbi.nlm.nih.gov/41470913/. The allowable pressure rating of polypropylene piping decreases with increasing temperature due to reduction in tensile strength and modulus as the material approaches its glass transition and softening temperatures. Evidence role: mechanism; source type: research. Supports: the temperature-dependent mechanical behavior of polypropylene. Scope note: Specific derating factors vary by material grade and must be obtained from manufacturer data or applicable standards ↩
