Subject: HPT (Hygienic Paper Toilet): A new dry toilet conceptfeaturing a biodegradable paper-insert and air-pressure transport mechanismDear Forum Members,I would like to share the theoretical and practicalfoundations of a new dry toilet concept with the international community, which
I have developed under the name HPT (Hygienic Paper Toilet). This innovation
combines the high comfort level of conventional flush toilets with the
ecological advantages of compost toilets, without their known disadvantages,
utilizing an entirely new mechanism.I. What is the fundamental principle of HPT?Feces and urine are temporarily deposited onto aspecial, wet-strength, and urine-resistant thin paper insert. This paper insert
completely lines the toilet bowl and covers the seating surface as well.The paper insert serves a triple function:1.    High hygiene and comfort: The user is guaranteed a cleanseating surface and bowl every single time. This completely eliminates the need
for conventional, chemical-based cleaning of the bowl.2.    Odor and insect barrier: The insert acts as a physicalbarrier, sealing the air space of the restroom from the collection tank, thus
preventing odors and insects from entering.3.    Gravitational material transportwith air-pressure assistance: The paper insert transports the human excreta (feces,urine), used toilet paper, and anal cleansing water (in case of bidet
functionality) through a closed pipeline into the collection tank. In the case
of a vertical and short pipeline, the transport operates purely via gravity.
For inclined or longer pipelines, an air-pressure differential maintained by a
fan between the collection tank and the restroom actively assists the
continuous and secure movement of the used paper insert. This combined
mechanism ensures that the collection tank can be located outside the building,
or that multiple toilet seats can connect to a single central tank.System Optimization: For residential/family use, it is highly recommendedto install a separate, standalone urine-WC dedicated solely to urination
alongside the main HPT unit. Since this separate unit is used exclusively for
urinating, its implementation reduces the specific paper consumption of the
primary HPT unit by approximately 70%.II. How does it fit into current public sanitationsystems?In urban and developed infrastructures worldwide,water-flush systems dominate (representing a share of approx. 98%) because they
provide the highest level of convenience. However, they are extremely
water-wasteful, generate large amounts of blackwater, and the valuable plant
nutrients (N, P, K) contained within are largely destroyed or end up polluting
the environment.Among sustainable alternatives, composting toiletshave the lowest ecological footprint and operating costs (no water demand,
recoverable nutrients). Despite this, their adoption rate in developed regions
(e.g., the EU) is less than 2%. This is primarily due to two factors: lower
user comfort and limited physical/architectural application areas (excluding
multi-family apartment buildings and public spaces).The HPT concept theoretically bridges the gap betweenthese two worlds, resolving these core issues:·        Theguaranteed sterile seating surface provides higher comfort than a conventional
flush toilet.·        Thanks tothe inclined pipeline and air-pressure assistance, it can be installed in
almost any architectural environment where flush toilets currently operate.·        Itsecological footprint and operating costs are even lower than those of current
composting toilet variants. It demonstrates better efficiency even compared to
the simplest and cheapest dry-litter toilets (bucket toilets), when considering
the human labor time and maintenance required for the latter. Furthermore, its
ecological footprint is significantly superior to traditional pit latrines.The Closed Ecological Chain: By connecting the use of HPT, therecovery of nutrients from human excreta, timber production (e.g.,
short-rotation energy plantations), and paper manufacturing, a carbon-negative,
closed-loop circular process can be established that sequesters more CO₂ than itemits. The system generates more energy and biomass than it consumes during
operation.It is crucial to emphasize that only a minorfraction—approximately 5%—of the resulting compost/human manure is required to
sustainably regenerate the timber used for the specific paper insert. The
remaining majority, roughly 95%, is freely available to be utilized for
cultivating other agricultural crops and plants. Additionally, the amount of
water required to manufacture the specific paper insert is a mere fraction of
the greywater generated and recovered during the overall process.

III. Technical FeasibilityThere are no technological barriers to the theoreticalfeasibility of the system; the components can be integrated from already
existing industrial solutions:1.    Collection and Treatment: Modern composting tanks alreadyexist that can process urine and cleansing water alongside feces without
requiring continuous manual addition of bulking agents. The centralized
composting of fecal matter and its agricultural/forestry utilization is a
validated technology today.2.    Pipeline Transport: The gravitational transport ofdiscrete, wrapped units within a closed pipe system, supported by air-pressure
differential, is a well-established practice in packaging and warehouse
logistics.3.    Raw Material (The Paper Insert): Although a paper insertspecifically designed for collecting human excreta is not currently on the
market, the manufacturing of papers with varying degrees of water and urine
resistance is commonplace in the paper industry. Based on my own testing,
certain 30 g/m² eco-friendly, wet-strength papers (such as certain floral
wrapping papers and specialized packaging papers) can retain water for 30 minutes
and urine for hours without losing their tensile strength. The estimated retail
material cost of such a paper insert is only about 18 HUF (~0.05 USD) per
piece. When introduced to nature or compost, these papers decompose 100% within
a few weeks, completely free of microplastics.As a retired forestry engineer, I have developed thetheoretical and circular model of this toilet system. I am not in a position to
undertake practical implementation, prototype manufacturing, or
commercialization. Therefore, I am looking for an industrial partner,
development company, or investor to adopt the theoretical concept and undertake
its full practical realization.IV. Questions for the SuSanA Community:1.    Does the community see potential inthis concept, and do you consider it professionally well-founded and viable? I
would be delighted to answer any questions and discuss further technical
details.2.    Through what channels, platforms, orspecific companies could one reach well-capitalized manufacturers who are open
to fully embracing this new dry-toilet concept, engaging in a know-how
transfer/technology partnership, and driving its industrial realization?Sincerely,Péter Schnörch
Retired Forestry Engineer
Hungary