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Hydrated Lime Treatment is a cost-effective chemical treatment method for faecal sludge from pits and trenches. It uses hydrated or slaked lime (calcium hydroxide: Ca(OH)2) as an additive to create a highly alkaline environment and thereby stabilise sludge from human waste. It thereby significantly reduces the risk of latrine sludge causing negative impacts on human health and the environment.

The pros’ and cons’ of lime treatment

Pros

Short treatment time (6 Log removal of E-coli in <1day)
Simple process which uses readily available material
For liquid sludge – a sanitised and stabilised effluent is created suitable for soil infiltration.

Cons High chemical input Highly-alkaline sludge and effluent created requires subsequent neutralisation Lime quality can impact dosage rates Potential health risks if not handled properly

Design Considerations The treatment process can either take place above ground in a separate tank or below ground by digging a pit and lining with a tarpaulin in order to avoid leakage of highly alkaline effluents into the ground. In areas with high groundwater level or in flood prone areas it is recommended to always use above ground tanks rather than digging a pit. Separate tanks may be needed for the preparation of the lime slurry and for the post-neutralisation of the treated effluent respectively.

Source: Speedy Sanititazion And Stabilization. Appendix 2. Lime Dosage Determination Procedure –WASTE.
Note: If you use agricultural lime (calcium carbonate) and not hydrated lime (calcium hydroxide), the process will not work;

How to use it?

• Hydrated lime treatment needs a reactor vessel which can either be an above ground tank (between 1-30m3) or a pit below ground with tarpaulin lining.
• An additional smaller container is needed for the preparation of the lime slurry (e.g. 200l plastic drum). See here for video on how to make the lime slurry
  https://youtu.be/3PZsxXK-il4
• For an even distribution of hydrated lime in the tank it is mixed into the sludge either manually with a shovel or wooden stick or with a mixing pump.
• The type of pump required depends on the consistency of the sludge. A
  separate pump is needed for removing the treated effluent from the tank
  and a shovel or vacuum pump for the
  solid removal.
• In addition a water testing kit (particularly for pH, E.coli, TSS and turbidity) is needed as well as personal protective equipment (PPE) like mask, gloves, boots, apron or suit and the respective chemicals (hydrated lime,
  magnesium sulphate if needed).

Further reading

Research on lime application – Emergency Sanitation Project https://emergencysanitationproject.wikispaces.com/file/view/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf/607343967/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf

Compendium of different sanitation technologies appropriate for emergency situations. Compendium of Sanitation Technologies in Emergencies (pending publication) German WASH Network, EAWAG, Global WASH Cluster.

Lime treatment as promising sludge sanitising method in emergencies Anderson, C. et al. (2015): Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation, UCBI, URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4661620 General overview on lime treatment and case study from the Philippines Strande, L. et al (2014): Faecal Sludge Management (FSM) book - Systems Approach for Implementation and Operation, page 110 ff., IWA Publishing, UK, URL: https://www.susana.org/en/resources/library/details/2100 Case study from Cambodia on Household-level application of hydrated lime Chakraborty et al. (2014): Household-level application of hydrated lime for on-site treatment and agricultural use of latrine sludge, 37th WEDC International Conference, Hanoi, Vietnam, URL: https://sanitationupdates.files.wordpress.com/2014/06/ide_wedc-final.pdf Case study from Haiti on hydrated lime treatment of sludge from Cholera Treatment Centres Taylor et al (2011): SOP for the physicochemical treatment of CTC wastewaters, Médecins Sans Frontières (MSF), URL: https://www.solutionsforwater.org/wp-content/uploads/2011/12/SOP_WWT_15_Dic_11_Final.pdf

Implementer’s Guide to Lime Stabilization for Septage Management in the Philippines (USAID) https://forum.susana.org/media/kunena/attachments/818/ImplementersGuidetoLimeStabilizationforSeptageManagementinthePhilippines.pdf

Hydrated Lime Treatment is a cost-effective chemical treatment method for faecal sludge from pits and trenches. It uses hydrated or slaked lime (calcium hydroxide: Ca(OH)2) as an additive to create a highly alkaline environment and thereby stabilise sludge from human waste. It thereby significantly reduces the risk of latrine sludge causing negative impacts on human health and the environment.

The pros’ and cons’ of lime treatment

Pros

Short treatment time (6 Log removal of E-coli in <1day)
Simple process which uses readily available material
For liquid sludge – a sanitised and stabilised effluent is created suitable for soil infiltration.

Cons High chemical input input
Highly-alkaline sludge and effluent created created
requires subsequent neutralisation neutralisation
Lime quality can impact dosage rates rates Potential health risks if not handled properly

Design Considerations The treatment process can either take place above ground in a separate tank or below ground by digging a pit and lining with a tarpaulin in order to avoid leakage of highly alkaline effluents into the ground. In areas with high groundwater level or in flood prone areas it is recommended to always use above ground tanks rather than digging a pit. Separate tanks may be needed for the preparation of the lime slurry and for the post-neutralisation of the treated effluent respectively.

Source: Speedy Sanititazion And Stabilization. Appendix 2. Lime Dosage Determination Procedure –WASTE.
Note: If you use agricultural lime (calcium carbonate) and not hydrated lime (calcium hydroxide), the process will not work;

How to use it?

• Hydrated lime treatment needs a reactor vessel which can either be an above ground tank (between 1-30m3) or a pit below ground with tarpaulin lining.
• An additional smaller container is needed for the preparation of the lime slurry (e.g. 200l plastic drum). See here for video on how to make the lime slurry
  https://youtu.be/3PZsxXK-il4
• For an even distribution of hydrated lime in the tank it is mixed into the sludge either manually with a shovel or wooden stick or with a mixing pump.
• The type of pump required depends on the consistency of the sludge. A
  separate pump is needed for removing the treated effluent from the tank
  and a shovel or vacuum pump for the
  solid removal.
• In addition a water testing kit (particularly for pH, E.coli, TSS and turbidity) is needed as well as personal protective equipment (PPE) like mask, gloves, boots, apron or suit and the respective chemicals (hydrated lime,
  magnesium sulphate if needed).

Further reading

Research on lime application – Emergency Sanitation Project https://emergencysanitationproject.wikispaces.com/file/view/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf/607343967/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf

Compendium of different sanitation technologies appropriate for emergency situations. Compendium of Sanitation Technologies in Emergencies (pending publication) German WASH Network, EAWAG, Global WASH Cluster.

Lime treatment as promising sludge sanitising method in emergencies Anderson, C. et al. (2015): Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation, UCBI, URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4661620 General overview on lime treatment and case study from the Philippines Strande, L. et al (2014): Faecal Sludge Management (FSM) book - Systems Approach for Implementation and Operation, page 110 ff., IWA Publishing, UK, URL: https://www.susana.org/en/resources/library/details/2100 Case study from Cambodia on Household-level application of hydrated lime Chakraborty et al. (2014): Household-level application of hydrated lime for on-site treatment and agricultural use of latrine sludge, 37th WEDC International Conference, Hanoi, Vietnam, URL: https://sanitationupdates.files.wordpress.com/2014/06/ide_wedc-final.pdf Case study from Haiti on hydrated lime treatment of sludge from Cholera Treatment Centres Taylor et al (2011): SOP for the physicochemical treatment of CTC wastewaters, Médecins Sans Frontières (MSF), URL: https://www.solutionsforwater.org/wp-content/uploads/2011/12/SOP_WWT_15_Dic_11_Final.pdf

Implementer’s Guide to Lime Stabilization for Septage Management in the Philippines (USAID) https://forum.susana.org/media/kunena/attachments/818/ImplementersGuidetoLimeStabilizationforSeptageManagementinthePhilippines.pdf

Hydrated Lime Treatment is a cost-effective chemical treatment method for faecal sludge from pits and trenches. It uses hydrated or slaked lime (calcium hydroxide: Ca(OH)2) as an additive to create a highly alkaline environment and thereby stabilise sludge from human waste. It thereby significantly reduces the risk of latrine sludge causing negative impacts on human health and the environment.

The pros’ and cons’ of lime treatment

Pros

Short treatment time (6 Log removal of E-coli in <1day)
Simple process which uses readily available material
For liquid sludge – a sanitised and stabilised effluent is created suitable for soil infiltration.

Cons Cons

High chemical input
Highly-alkaline sludge and effluent created
requires subsequent neutralisation
Lime quality can impact dosage rates Potential health risks if not handled properly

Design Considerations The treatment process can either take place above ground in a separate tank or below ground by digging a pit and lining with a tarpaulin in order to avoid leakage of highly alkaline effluents into the ground. In areas with high groundwater level or in flood prone areas it is recommended to always use above ground tanks rather than digging a pit. Separate tanks may be needed for the preparation of the lime slurry and for the post-neutralisation of the treated effluent respectively.

Source: Speedy Sanititazion And Stabilization. Appendix 2. Lime Dosage Determination Procedure –WASTE.
Note: If you use agricultural lime (calcium carbonate) and not hydrated lime (calcium hydroxide), the process will not work;

How to use it?

• Hydrated lime treatment needs a reactor vessel which can either be an above ground tank (between 1-30m3) or a pit below ground with tarpaulin lining.
• An additional smaller container is needed for the preparation of the lime slurry (e.g. 200l plastic drum). See here for video on how to make the lime slurry
  https://youtu.be/3PZsxXK-il4
• For an even distribution of hydrated lime in the tank it is mixed into the sludge either manually with a shovel or wooden stick or with a mixing pump.
• The type of pump required depends on the consistency of the sludge. A
  separate pump is needed for removing the treated effluent from the tank
  and a shovel or vacuum pump for the
  solid removal.
• In addition a water testing kit (particularly for pH, E.coli, TSS and turbidity) is needed as well as personal protective equipment (PPE) like mask, gloves, boots, apron or suit and the respective chemicals (hydrated lime,
  magnesium sulphate if needed).

Further reading

Research on lime application – Emergency Sanitation Project https://emergencysanitationproject.wikispaces.com/file/view/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf/607343967/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf

Compendium of different sanitation technologies appropriate for emergency situations. Compendium of Sanitation Technologies in Emergencies (pending publication) German WASH Network, EAWAG, Global WASH Cluster.

Lime treatment as promising sludge sanitising method in emergencies Anderson, C. et al. (2015): Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation, UCBI, URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4661620 General overview on lime treatment and case study from the Philippines Strande, L. et al (2014): Faecal Sludge Management (FSM) book - Systems Approach for Implementation and Operation, page 110 ff., IWA Publishing, UK, URL: https://www.susana.org/en/resources/library/details/2100 Case study from Cambodia on Household-level application of hydrated lime Chakraborty et al. (2014): Household-level application of hydrated lime for on-site treatment and agricultural use of latrine sludge, 37th WEDC International Conference, Hanoi, Vietnam, URL: https://sanitationupdates.files.wordpress.com/2014/06/ide_wedc-final.pdf Case study from Haiti on hydrated lime treatment of sludge from Cholera Treatment Centres Taylor et al (2011): SOP for the physicochemical treatment of CTC wastewaters, Médecins Sans Frontières (MSF), URL: https://www.solutionsforwater.org/wp-content/uploads/2011/12/SOP_WWT_15_Dic_11_Final.pdf

Implementer’s Guide to Lime Stabilization for Septage Management in the Philippines (USAID) https://forum.susana.org/media/kunena/attachments/818/ImplementersGuidetoLimeStabilizationforSeptageManagementinthePhilippines.pdf

Hydrated Lime Treatment is a cost-effective chemical treatment method for faecal sludge from pits and trenches. It uses hydrated or slaked lime (calcium hydroxide: Ca(OH)2) as an additive to create a highly alkaline environment and thereby stabilise sludge from human waste. It thereby significantly reduces the risk of latrine sludge causing negative impacts on human health and the environment.

The pros’ and cons’ of lime treatment

Pros

Short treatment time (6 Log removal of E-coli in <1day)
Simple process which uses readily available material
For liquid sludge – a sanitised and stabilised effluent is created suitable for soil infiltration.

Cons

High chemical input
Highly-alkaline sludge and effluent created
requires subsequent neutralisation
Lime quality can impact dosage rates Potential health risks if not handled properly

Design Considerations The treatment process can either take place above ground in a separate tank or below ground by digging a pit and lining with a tarpaulin in order to avoid leakage of highly alkaline effluents into the ground. In areas with high groundwater level or in flood prone areas it is recommended to always use above ground tanks rather than digging a pit. Separate tanks may be needed for the preparation of the lime slurry and for the post-neutralisation of the treated effluent respectively.

Source: Speedy Sanititazion And Stabilization. Appendix 2. Lime Dosage Determination Procedure –WASTE.
Note: If you use agricultural lime (calcium carbonate) and not hydrated lime (calcium hydroxide), the process will not work; work.

How to use it?

• Hydrated lime treatment needs a reactor vessel which can either be an above ground tank (between 1-30m3) or a pit below ground with tarpaulin lining.
• An additional smaller container is needed for the preparation of the lime slurry (e.g. 200l plastic drum). See here for video on how to make the lime slurry
  https://youtu.be/3PZsxXK-il4
• For an even distribution of hydrated lime in the tank it is mixed into the sludge either manually with a shovel or wooden stick or with a mixing pump.
• The type of pump required depends on the consistency of the sludge. A
  separate pump is needed for removing the treated effluent from the tank
  and a shovel or vacuum pump for the
  solid removal.
• In addition a water testing kit (particularly for pH, E.coli, TSS and turbidity) is needed as well as personal protective equipment (PPE) like mask, gloves, boots, apron or suit and the respective chemicals (hydrated lime,
  magnesium sulphate if needed).

Further reading

Research on lime application – Emergency Sanitation Project https://emergencysanitationproject.wikispaces.com/file/view/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf/607343967/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf

Compendium of different sanitation technologies appropriate for emergency situations. Compendium of Sanitation Technologies in Emergencies (pending publication) German WASH Network, EAWAG, Global WASH Cluster.

Lime treatment as promising sludge sanitising method in emergencies Anderson, C. et al. (2015): Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation, UCBI, URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4661620 General overview on lime treatment and case study from the Philippines Strande, L. et al (2014): Faecal Sludge Management (FSM) book - Systems Approach for Implementation and Operation, page 110 ff., IWA Publishing, UK, URL: https://www.susana.org/en/resources/library/details/2100 Case study from Cambodia on Household-level application of hydrated lime Chakraborty et al. (2014): Household-level application of hydrated lime for on-site treatment and agricultural use of latrine sludge, 37th WEDC International Conference, Hanoi, Vietnam, URL: https://sanitationupdates.files.wordpress.com/2014/06/ide_wedc-final.pdf Case study from Haiti on hydrated lime treatment of sludge from Cholera Treatment Centres Taylor et al (2011): SOP for the physicochemical treatment of CTC wastewaters, Médecins Sans Frontières (MSF), URL: https://www.solutionsforwater.org/wp-content/uploads/2011/12/SOP_WWT_15_Dic_11_Final.pdf

Implementer’s Guide to Lime Stabilization for Septage Management in the Philippines (USAID) https://forum.susana.org/media/kunena/attachments/818/ImplementersGuidetoLimeStabilizationforSeptageManagementinthePhilippines.pdf

Hydrated Lime Treatment is a cost-effective chemical treatment method for faecal sludge from pits and trenches. It uses hydrated or slaked lime (calcium hydroxide: Ca(OH)2) as an additive to create a highly alkaline environment and thereby stabilise sludge from human waste. It thereby significantly reduces the risk of latrine sludge causing negative impacts on human health and the environment.

The pros’ and cons’ of lime treatment

Pros

Short treatment time (6 Log removal of E-coli in <1day)
Simple process which uses readily available material
For liquid sludge – a sanitised and stabilised effluent is created suitable for soil infiltration.

Cons

High chemical input
Highly-alkaline sludge and effluent created
requires subsequent neutralisation
Lime quality can impact dosage rates Potential health risks if not handled properly

Design Considerations The treatment process can either take place above ground in a separate tank or below ground by digging a pit and lining with a tarpaulin in order to avoid leakage of highly alkaline effluents into the ground. In areas with high groundwater level or in flood prone areas it is recommended to always use above ground tanks rather than digging a pit. Separate tanks may be needed for the preparation of the lime slurry and for the post-neutralisation of the treated effluent respectively.

Source: Speedy Sanititazion And Stabilization. Appendix 2. Lime Dosage Determination Procedure –WASTE.
Note: If you use agricultural lime (calcium carbonate) and not hydrated lime (calcium hydroxide), the process will not work.

How to use it?

• Hydrated lime treatment needs a reactor vessel which can either be an above ground tank (between 1-30m3) or a pit below ground with tarpaulin lining.
• An additional smaller container is needed for the preparation of the lime slurry (e.g. 200l plastic drum). See here for video on how to make the lime slurry
  https://youtu.be/3PZsxXK-il4
• For an even distribution of hydrated lime in the tank it is mixed into the sludge either manually with a shovel or wooden stick or with a mixing pump.
• The type of pump required depends on the consistency of the sludge. A
  separate pump is needed for removing the treated effluent from the tank
  and a shovel or vacuum pump for the
  solid removal.
• In addition a water testing kit (particularly for pH, E.coli, TSS and turbidity) is needed as well as personal protective equipment (PPE) like mask, gloves, boots, apron or suit and the respective chemicals (hydrated lime,
  magnesium sulphate if needed).

Further reading

Research on lime application – Emergency Sanitation Project https://emergencysanitationproject.wikispaces.com/file/view/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf/607343967/HIF%20Line%201%20Speedy%20Sanitization%20%26%20Stabilization%20Final_Report_draft_23.5.2016.pdf

Compendium of different sanitation technologies appropriate for emergency situations. Compendium of Sanitation Technologies in Emergencies (pending publication) German WASH Network, EAWAG, Global WASH Cluster.

Lime treatment as promising sludge sanitising method in emergencies Anderson, C. et al. (2015): Lactic Acid Fermentation, Urea and Lime Addition: Promising Faecal Sludge Sanitizing Methods for Emergency Sanitation, UCBI, URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4661620 General overview on lime treatment and case study from the Philippines Strande, L. et al (2014): Faecal Sludge Management (FSM) book - Systems Approach for Implementation and Operation, page 110 ff., IWA Publishing, UK, URL: https://www.susana.org/en/resources/library/details/2100 Case study from Cambodia on Household-level application of hydrated lime Chakraborty et al. (2014): Household-level application of hydrated lime for on-site treatment and agricultural use of latrine sludge, 37th WEDC International Conference, Hanoi, Vietnam, URL: https://sanitationupdates.files.wordpress.com/2014/06/ide_wedc-final.pdf Case study from Haiti on hydrated lime treatment of sludge from Cholera Treatment Centres Taylor et al (2011): SOP for the physicochemical treatment of CTC wastewaters, Médecins Sans Frontières (MSF), URL: https://www.solutionsforwater.org/wp-content/uploads/2011/12/SOP_WWT_15_Dic_11_Final.pdf

Implementer’s Guide to Lime Stabilization for Septage Management in the Philippines (USAID) https://forum.susana.org/media/kunena/attachments/818/ImplementersGuidetoLimeStabilizationforSeptageManagementinthePhilippines.pdf