Manejo del agua en la vivienda: beneficios acelerados para la salud derivados del abastecimiento de agua mejorado
Chemical methods of water treatment (inglés)
| Coagulant | Community/Household Use | Advantages | Disadvantages | Cost* | Comments |
| Alum (aluminum sulfate, etc.), alum potash | Yes/rare-moderate | Community use common; simple technology | Difficult to optimize without training and equipment | Moderate? | Proper use requires skill |
| Iron salts (ferric chloride or sulfate) | Yes/rare | Same as Alum | Same as Alum | Moderate? | Proper use requires skill |
| Lime (Ca(OH2)), lime+soda ash (Na2CO3), caustic soda (NaOH) | Yes/rare-moderate | Same as Alum | Same as Alum; pH control and neutralization a problem; hazardous chemicals | Moderate to high? | Softeners; not applicable to many waters |
| Soluble synthetic organic polymers | Yes/no-rare | Improve coagulation with alum and iron salts | Same as Alum; hard to dose; need training & equipment; hazardous chemicals | High | Use with other coagulants; limited availability |
| Natural polymers (carbohydrates) from seeds, nuts, beans, etc. | Rare/Yes | ||||
| (in some developing countries) | Effective, available and culturally accepted in some places | Source plant required; training and skill required; cultural acceptability; may be toxic | Low | Traditional use based on historical practices |
| Adsorbent | Community/Household Use | Advantages | Disadvantages | Cost* | Comments |
| Clays | Rare/rare-moderate | Some efficiently adsorb microbes; adaptable to many treatment formats | Some adsorb microbes poorly; availability limited | Low to moderate | Use as an adsorbent or coagulant |
| Charcoal (C), Activated Carbon (AC) | Moderate/Moderate; (AC more in developed world; C more in developing world) | Adaptable to many treatment formats; charcoal often readily available | Poor microbe adsorption; can degrade microbial quality | Moderate (C ) to high (AC) | Used as adsorbents or coagulants; use varies regionally; C use based on traditional practice |
| Crushed organic matter: seeds, rice, etc. | No-very rare/Rare-moderate in some countries | Ditto charcoal and carbon | Poor microbe adsorption; can degrade microbial quality | Low | Used as adsorbent or coagulant |
| Exchange Resin | Community/Household Use | Advantages- | Disadvantages | Cost* | Comments |
| Softening resins | Yes/Yes | Easy to use | Do not inactivate microbes; spent resin replacement and disposal required; unavailable in some parts of the world | High | Lack of microbial reduction makes them unsuitable for microbial reductions in household water treatment |
| Deionizing Resins | Yes/Yes | Inactivate microbes; easy to use | Not recommended for drinking water; spent resin replacement and disposal required; unavailable in some parts of the world | High | The effects on long-term consumption of deionised water on health are not fully understood. |
| Iodine Disinfection (tri-iodide and penta-iodide) | No/Yes | Inactivates microbes; easy to use | Risk of soluble iodine leaching into water; spent resin replacement and disposal required; unavailable in some parts of the world | High | Difficult to determine useable life without added technology; impractical and limited availability in developing world |
| Adsorbent and scavenging resins | No/Yes | Easy to use | Not likely to inactivate microbes; microbial colonization and release a concern; not available in some parts of the world | High | Difficult to determine useable life without added technology; impractical and limited availability in many parts of the world |
| Disinfectant | Community/Household Use | Advantages | Disadvantages | Cost* | Comments |
| Free chlorine (NaOCl, Ca(OCl)2 | Yes/Yes (worldwide, but not in some regions) | Easy to use; effective against most pathogens; stable residual | Not available worldwide; some users object to taste and odor | Low | The most widely used drinking water disinfectant; proven technology |
| Electro-chemically generated oxidant from NaCl | Yes/Yes (limited distribution) | Easy to use; effective against most pathogens; stable residual | Not available worldwide; some users object to taste and odor (mostly chlorine) | Low | Practical for worldwide use; can generate on site by electrolysis of NaCl; proven technology |
| Chloramines (monochloramine) | Yes/Rare (less widely used than free chlorine; must react free chlorine with ammonia | Stable residual | Less effective microbiocide than free chlorine; requires skill and equipment to generate on-site; household use impractical | Moderate | More difficult to use than free chlorine; potentially available where free chlorine is used but requires ammonia source |
| Ozone | Yes/Rare(less widely than free chlorine; mostly in Europe) | Highly micro-biocidal; | No residual; Generate onsite; hard to use; need special facilities and trained personnel; hazardous | High | Not practical for household use in many regions and countries |
| Chlorine Dioxide | Yes/Rare (much less use than free chlorine; for individual use by acidifying chlorite or chlorate) | Highly micro-biocidal; | Poor residual; generate on-site; some technologies require special facilities, trained personnel and are hazardous; toxicologic concerns | High | Can be generated on-site by reacting chlorate or chlorite salts with acids; reactants may not be available and some are hazardous |
| Acids (especially lime juice and mineral acids) and hydroxide (caustic) | Limited/Limited (in community systems mineral acid and base for pH control; lime (CaO) and soda ash for chemical softening; in household Treatment lime juice for inactivation of V. cholerae | Acids inactivate V. cholerae & some other bacteria; limes and chemicals widely available | Limited microbiocidal activity; CaO use requires special facilities and trained personnel and is hazardous; CaO process difficult to control | High for CaO; low-moderate for lime juice | Lime juice has been reported to be effective for cholera control at the household level; Chemical acids and lime precipitation not practical for household use |
| Combined chlorina-tion, coag-ulation-flocculation-filtration systems | Yes/Yes As sequential processes in community systems and as combined processes in household systems | Highly effective for microbe reductions | Availability now limited; requires some training and skill; efficacy varies with water quality; | High | Limited availability and higher cost (compared to chlorine) are barriers to household use in some countries and regions |
