Drain Cleaners
The blockages in sinks, toilets, and bathtubs are primarily caused by substances such as fats, proteins, cellulose, and calcium soaps. Calcium soaps result from the reaction of washing soap with heavy metal ions like calcium and magnesium, as well as the products of alkaline decomposition of fatty dirt. These substances mix with body dirt and hair dirt, adhering to the pipe walls and causing blockages in the sewer system.
Types of Sewer Cleaning Agents
1. Strong Acid, Strong Base, and Oxidizer Type
These cleaners are effective in eliminating blockage, but they are not safe. Pipe dredging agents composed of sodium hydroxide, aluminum powder, etc., according to their strong alkalinity, saponify the blockage and grease and other organic pollutants adhering to the pipe wall, and then corrode, destroy, until dissolving the hair, fibers, cloth strips, vegetable leaves and other organic matter in the drain pipe, and can eliminate microorganisms in the pipe and remove odor. The strong oxidation reaction of aluminum powder generates hydrogen gas and heats up, generating a loose mechanical driving force. The smaller the particle size of aluminum powder, the faster the heat generation, among which 30-42 days account for about 80% is good. Some additives and surfactants have a suspending, dispersing, emulsifying and saponifying effect on mud and oil. The biochemical reaction of enzymes accelerates the dredging effect.
2. Mild Sewer Cleaning Agents
The most commonly used unblocking components are sulfur-containing compounds (such as sodium thiosulfate and mercaptocarboxylate salts) used as depilatories in cosmetics, which can decompose the most difficult hair blockages. Surface-active agents help remove oil stains and increase the suspension and dispersion of dirt. Given the high difficulty and particularity of sewer cleaning, fluorinated surfactants are very effective even when added in amounts of 0.3% to 0.5%. Since the walls of sewer pipes are often vertical, the viscosity of the cleaning agent can extend its retention time on the pipe wall. Common thickeners include inexpensive sodium carboxymethyl cellulose. However, incorporating thickeners into redox cleaning agents presents certain challenges. In inorganic salts, sodium chloride is commonly used. Inorganic salts help the cleaning agent sink to the bottom of the blockage and play an unblocking role. Heavy metal ions form insoluble salts with depilatories and sodium carboxymethyl cellulose, which should be strictly avoided. Sulfides and urea are effective corrosion inhibitors for steel pipes; organic solvents help dissolve, disperse, and emulsify grease and calcium soaps.
Formulations
Formulation 1: Exothermic Sewer Pipe Unblocking and Cleaning Agent
| Raw Material | Mass Fraction / % |
|---|---|
| Sodium Hypochlorite | 35~50 |
| Phosphate | 20~25 |
| Nitrate | 15~20 |
| Aluminum Shavings | 10~20 |
| Sodium Dichloroisocyanurate | 2~7 |
Formulation 2: Oxidizing Type Liquid Sewer Cleaning Agent
| Raw Material | Mass Fraction / % |
|---|---|
| Sodium Hypochlorite | 5.0 |
| Sodium Hydroxide | 2.0 |
| Sodium Silicate | 1.5 |
| Sodium Xylenesulfonate | 0.30 |
| Sodium Lauryl Sulfate | 1.0 |
| Sodium Lauryl Sarcosinate | 0.30 |
| Water | Balance |
The thickener used is a combination of three anionic surfactants, which gives the detergent a certain viscosity and resistance to the oxidation of hypochlorite salts. The active half-life of the hypochlorite salts is more than half a year, and the viscosity is 0.1 to 0.225 Pa.
Formulation 3: Alkaline Metal Hydroxide-Free Drain Cleaner
| Raw Material | Mass Fraction / % |
|---|---|
| Alkylbenzenesulfonic Acid Sodium | 1.5 |
| Carboxymethyl Cellulose (CMC) | 3.0 |
| Thioglycolic Acid | 3.0 |
| N-Methyl-2-pyrrolidone | 3.0 |
| Sodium Chloride | 15.0 |
| Water | Balance |
N-Methyl-2-pyrrolidone, in addition to acting as a solvent, can also produce an effective synergistic unblocking effect with sulfides and other compounds.
Formulation 4: Alkaline Metal Hydroxide-Free Toilet Sewer Drain Cleaner
| Raw Material | Mass Fraction / % |
|---|---|
| Ethanol | 2~4 |
| Aniline | 0.5~1 |
| Paper Fiber Debriding Agent | 1~3 |
| Sodium Hydrosulfide | 0.5~1 |
| Surfactant | 0.1~1 |
| Urotropin | 0.5~1 |
| Hydrochloric Acid | 3~8 |
| Phosphoric Acid | 1~3 |
| Water | Balance |
This formulation utilizes ethanol for its penetrating and dissolving properties, aniline for its reactivity with sulfur compounds, and a combination of debriding agents and hydrosulfide to break down blockages. The inclusion of surface-active agents enhances the cleaning effect, while urotropin, hydrochloric acid, and phosphoric acid contribute to the dissolution and removal of various blockage materials.
Conclusion
Sewer cleaning agents play a critical role in maintaining unclogged and functional sewer systems. The choice of cleaning agent depends on the nature and severity of the blockage. It is essential to follow safety precautions when using these chemicals, as some can be highly reactive or corrosive. The formulations provided offer a range of options, from strong alkaline and oxidizing agents to milder alternatives that are safer to use but still effective for clearing blockages.