Collection Systems for Use in Offset Pit Latrines Having Pour Flush Latrine Pans, Collectors, Offset Pit Latrines and Related Methods

Abstract

The invention described herein includes a latrine pan and collector system for use in an offset pit latrine. The system permits use of a latrine pan having a flapper in an offset leach pit context, and eliminated the necessity of large scale installation of a concrete collection box, which can collect unsanitary debris. The system of the invention includes (1) a pour-flush latrine pan and (2) a collector. The collector includes a collector body that engages the latrine pan, defines a discharge opening, and secures an inclined surface sloping downwardly between an impact zone positioned beneath the outlet of the latrine pan and the discharge opening, the collector body securing the inclined surface at a position sufficiently distant from the underside of the latrine pan so that the inclined surface does not impede pivoting of the flapper, whereby material discharged from the outlet of the latrine pan contacts the inclined surface at the impact zone and slides downwardly from the impact zone to the discharge opening. Also included is the collector described above, related latrine structures and methods.

1 . A collection system for use in an offset pit latrine comprising:
 (a) a pour-flush latrine pan mountable at a surface comprising a collection basin and a flapper, the collection basin having an upper bowl portion tapering to an outlet extending through a wall of the collection basin at a lower end of the collection basin, the flapper comprising a counterbalance device and a coverplate disposed on opposite sides of a pivot,   
       the coverplate having a shape adapted to cover the outlet of the collection basin when the coverplate is engaged against the lower end of the collection basin, the flapper being pivotally mounted against the collection basin such that the coverplate engages against the lower end of the collection basin when a pivotal force attributable to the counterbalance device is greater than a pivotal force applied to the coverplate that engages the lower end of the collection basin; and
 (b) a collector for directing towards an offset leach pit a material discharged from a latrine pan having a flapper comprising a counterbalance device and a coverplate pivotally mounted against the latrine pan, the collector comprising a collector body that engages the latrine pan, defines a discharge opening, and secures an inclined surface sloping downwardly between an impact zone positioned beneath the outlet of the latrine pan and the discharge opening, the collector body securing the inclined surface at a position sufficiently distant from the underside of the latrine pan so that the inclined surface does not impede pivoting of the flapper, 
 whereby material discharged from the outlet of the latrine pan contacts the inclined surface at the impact zone and slides downwardly from the impact zone to the discharge opening. 
 
     
     
         2 . The system of  claim 1 , wherein the collector body engages the latrine pan about the entire periphery of an upper end of the latrine pan. 
     
     
         3 . The system of  claim 1 , wherein the collector body has a flange disposed about the periphery of its upper end for engaging a conforming portion of the latrine pan. 
     
     
         4 . The system of  claim 3 , wherein the collector body and the latrine pan define a collection cavity when the collector body and the latrine pan are engaged and the interior of the collection cavity communicating with the outside of the cavity substantially only by way of the discharge opening of the collector and the outlet of the latrine pan. 
     
     
         5 . The system of  claim 1 , wherein the discharge opening is circular. 
     
     
         6 . The system of  claim 1 , wherein the collector body comprises an adapter portion disposed about the discharge opening for engaging a pipe with the body in a conformation whereby the interior of the pipe fluidly communicates with the discharge opening. 
     
     
         7 . The system of  claim 1 , wherein the collection body and the inclined surface are unitary. 
     
     
         8 . The system of  claim 1 , wherein the inclined surface is substantially planar. 
     
     
         9 . The system of  claim 1 , wherein the inclined surface is rounded. 
     
     
         10 . The system of  claim 1 , wherein the shape of the coverplate of the flapper defines a channel that engages the lower end of the collection basin about at least a portion of its perimeter when the coverplate is engaged against the lower end of the collection basin. 
     
     
         11 . The system of  claim 10 , wherein the shape of the coverplate includes a convex portion that extends within the outlet of the collection basin when the coverplate is engaged against the lower end of the collection basin. 
     
     
         12 . The system of  claim 10 , wherein the channel contains a liquid that forms a liquid seal between a first surface of the cover plate and the lower end of the collection basin that prevents or reduces a flow of a sewage gas from a second side of the coverplate to the first side of the coverplate. 
     
     
         13 . The system of  claim 1 , wherein the flapper is pivotally mounted to the exterior of the collection basin of the latrine pan. 
     
     
         14 . The system of  claim 1 , wherein the collector pan is adapted to be self-stacking. 
     
     
         15 . A method of preventing or reducing a flow of a sewage gas and/or flying insect transit from an offset leach pit comprising installing in a slab the system of  claim 1 . 
     
     
         16 . The method of  claim 15 , wherein the flow of the sewage gas is reduced by at least 50% as compared to a conventional open offset leach pit. 
     
     
         17 . The method of  claim 15 , wherein the sewage gas is hydrogen sulfide or ammonia. 
     
     
         18 . A method of reducing the incidence of adverse health effects caused by sewage gas exposure and/or insect transmission in a latrine-using individual comprising installing over an offset leach pit the system of  claim 1 . 
     
     
         19 . The method of  claim 18 , wherein the adverse health effect is chosen from mucus membrane irritation, sore throat, cough, shortness of breath, respiratory ailments, fluid accumulation in the lungs, fatigue, pneumonia, loss of appetite, headaches, irritability, poor memory, dizziness, loss of consciousness and death. 
     
     
         20 . A method of installing an offset pour-flush latrine comprising fitting the system  claim 1  in fluid communication with an offset leach pit. 
     
     
         21 . The method of  claim 20 , wherein the discharge opening of the collector and the leach pit are separated by at least one meter. 
     
     
         22 . The method of  claim 20 , wherein the system is fitted into a cement slab. 
     
     
         23 . The method of  claim 20 , wherein the cement slab contains a footbed on either side of the collection basin to facilitate delivery of a bowel movement as near as possible to the outlet of the basin. 
     
     
         24 . A pour-flush offset pit latrine comprising an offset leach pit in fluid communication with the collection cavity of the system of  claim 1 . 
     
     
         25 . The latrine of  claim 24 , sited in a public sanitation facility. 
     
     
         26 . The latrine of  claim 24 , sited in a family residence. 
     
     
         27 . A method of sustainably and hygienically removing human excreta from human contact comprising
 providing a latrine of  claim 24 ;   delivering to the coverplate of the latrine pan a bowel movement of a user, wherein the bowel movement rest upon a first surface of the coverplate;   applying to the bowel movement-bearing coverplate a water stream such that the pivotal force exerted on the coverplate exceeds the pivotal force exerted on the counterbalance device causing the coverplate to become disengaged from the lower end of the basin such that the coverplate and the lower end are spaced apart sufficiently and the bowel movement is released from the surface of the cover plate, descending downwardly towards and contacting the inclined surface of the collector, and sliding downwardly to egress through the discharge opening;   
       wherein upon release of the bowel movement, the coverplate re-engages against the lower end of the collection basin and a liquid seal is formed between the first surface of the coverplate and the lower end of the collection basin. 
     
     
         28 . The method of  claim 27 , wherein the water stream is applied by manually pouring water into the collection basin using a water dispensing vessel. 
     
     
         29 . A collector for directing toward an offset leach pit material discharged from a latrine pan having a flapper pivotally mounted against the latrine pan, the collector comprising a collector body that engages the latrine pan, defines a discharge opening, and secures an inclined surface sloping downwardly between an impact zone positioned beneath the outlet of the latrine pan and the discharge opening, the collector body securing the inclined surface at a position sufficiently distant from the underside of the latrine pan that the inclined surface does not impede pivoting of the flapper, whereby material discharged from the outlet of the latrine pan contacts the inclined surface at the impact zone and is able to slide downwardly from the impact zone to the discharge opening. 
     
     
         30 . The collector of  claim 29 , wherein the collector body engages the latrine pan about the entire periphery of an upper end of the collector body. 
     
     
         31 . The collector of  claim 29 , wherein the body has a flange disposed about the periphery of its upper end for engaging a conforming portion of the latrine pan. 
     
     
         32 . The collector of  claim 29 , wherein the body and the latrine pan define a cavity when the body and the latrine pan are engaged, the interior of the cavity communicating with the outside of the cavity substantially only by way of the discharge opening and the outlet of the latrine pan. 
     
     
         33 . The collector of  claim 29 , wherein the discharge opening is circular. 
     
     
         34 . The collector of  claim 29 , wherein the collector body comprises an adapter portion disposed about the discharge opening for engaging a pipe with the collector body in a conformation whereby the interior of the pipe fluidly communicates with the discharge opening. 
     
     
         35 . The collector of  claim 29 , wherein the body and the inclined surface are unitary. 
     
     
         36 . The collector of  claim 29 , wherein the inclined surface is substantially planar. 
     
     
         37 . The collector of  claim 29 , wherein the inclined surface is rounded.