Skip to main content
SpringerLink
Log in

Sewerage force adjustment technology for energy conservation in vacuum sanitation systems

  • Published:
Chinese Journal of Mechanical Engineering Submit manuscript

Abstract

The vacuum sanitation is the safe and sound disposal approach of human excreta under the specific environments like flights, high speed trains and submarines. However, the propulsive force of current systems is not adjustable and the energy consumption does not adapt to the real time sewerage requirement. Therefore, it is important to study the sewerage force adjustment to improve the energy efficiency. This paper proposes an energy conservation design in vacuum sanitation systems with pneumatic ejector circuits. The sewerage force is controlled by changing the systematic vacuum degree according to the amount of the excreta. In particular, the amount of the excreta is tested by liquid level sensor and mass sensor. According to the amount of the excreta, the relationship between the excreta amount and the sewerage force is studied to provide proper propulsive force. In the other aspect, to provide variable vacuum degrees for different sanitation requirements, the suction and discharge system is designed with pneumatic vacuum ejector. On the basis of the static flow-rate characteristics and the vacuum generation model, the pressure response in the ejector circuit is studied by using the static flow rate characteristics of the ejector and air status equation. The relationship is obtained between supplied compressed air and systematic vacuum degree. When the compressed air is supplied to the ejector continuously, the systematic vacuum degree increases until the vacuum degree reaches the extreme value. Therefore, the variable systematic vacuum degree is obtained by controlling the compressed air supply of the ejector. To verify the effect of energy conservation, experiments are carried out in the artificial excreta collection, and the variable vacuum-degree design saves more than 30% of the energy supply. The energy conservation is realized effectively in the new vacuum sanitation systems with good application prospect. The proposed technology provides technological support for the energy conservation of vacuum sanitation systems.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. KELEMAN M. Economics of wastewater treatment codigestion [C]//Proceedings of the 4th International Conference on Energy Sustainability, ES, Phoenix, Arizona, USA, May 17–22, 2010: 595–608.

  2. JENSSEN P, HEYERDAHL P, WARMER W, et al. Local recycling of wastewater and wet organic waste, a step towards the zero emission community[C]//Proceedings of 8th International Conference on Environmental Science and Technology, Lemnos, Greece, Sep. 8–10, 2003: 357–364.

  3. TENG Honghua. Pneumatic system design of vacuum water-saving toilet in the train[J]. Chinese Hydraulics & Pneumatics, 2006(3): 55–57.

    Google Scholar 

  4. FLERI E, GALLIANO P, HARRISON M. Proposal for a zero-gravity toilet facility for the space station[R]. National Aeronautics and Space Administration, U.S.: NASA-CR-183151.

  5. CAI Maolin, KAWASHIMA K, KAGAWA T. Power assessment of flowing compressed air[J]. ASME Journal of Fluids Engineering, 2006, 128(3): 402–405.

    Article  Google Scholar 

  6. FUJINO K, TANIGUCHI K, YAMAMOTO N. Study on pneumatic supply system in Shinkansen railway vehicle[J]. Journal of the Japan Fluid Power System Society, 2010, 41(5): 92–97.

    Google Scholar 

  7. DUAN Jinming, ZHOU Jingxuan. Studies on frictional pressure drop of gas-non-Newtonian fluid two-phase flow in vacuum sewers[J]. Civil Engineering and Environmental Systems, 2006, 23(1): 1–10.

    Article  MathSciNet  Google Scholar 

  8. GUO Zhonghua, LI Xin, LI Xiaoning, et al. Study on pressure response of ejector vacuum circuit[J]. International Journal of Fluid Power, 2011, 12(1): 51–58.

    Google Scholar 

  9. CHHABRA R, RICHARDSON J. Non-newtonian flow in the process industries[M]. Oxford, UK: Butterworth-Heinemann, 1999.

    Google Scholar 

  10. CAI Maolin, KAGAWA T. Energy consumption assessment and energy loss analysis in pneumatic system[J]. Chinese Journal of Mechanical Engineering, 2007, 43(9): 69–74. (in Chinese)

    Article  Google Scholar 

  11. ONEYAMA N, FAN Wei, ZHANG Hongli, et al. Flow rate characteristics measurement of regulators based on the pressure response in an isothermal tank[J]. Chinese Journal of Mechanical Engineering, 2009, 22(5): 633–638.

    Article  Google Scholar 

  12. KAWASHIMA K, KAGAWA T. Unsteady flow generator for gases using isothermal chamber[J]. Measurement, 2003, 33(4): 333–340.

    Article  Google Scholar 

  13. KAWASHIMA K, ISHII Y, FUNAKI T, et al. Determination of flow rate characteristics of pneumatic solenoid valves using an isothermal chamber[J]. ASME Journal of Fluid Engineering, 2004, 126(3): 273–279.

    Article  Google Scholar 

  14. GB/T18092-2000, Water-free sanitary toilet[S]. National Standards of the People’s Republic of China, 2000: 11–12.

    Google Scholar 

  15. LI Min, ZHOU Jingxuan, WEN Xingsuo. Gas-liquid ratio and its relationship with energy consumption in vacuum sewerage system[J]. Water and Wastewater Engineering, 2010, 36(12): 69–72.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China

    Zhonghua Guo & Xiaoning Li

  2. Precision and Intelligence Laboratory, Tokyo Institute of Technology, Yokohama, 226-8503, Japan

    Toshiharu Kagawa

Authors
  1. Zhonghua Guo
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Xiaoning Li
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Toshiharu Kagawa
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Zhonghua Guo.

Additional information

This project is supported by Doctor Innovation Fund of Nanjing University of Science and Technology of China(Grant No. 20080407), and Joint-PhD Program of China Scholarship Council(Grant No. 2008104777)

GUO Zhonghua, born in 1983, is currently a lecturer at School of Mechanical Engineering, Nanjing University of Science and Technology, China. She received her PhD degree from Nanjing University of Science and Technology, China, in 2012. Her research interests include pneumatic components, pneumatic transmission and control, etc.

LI Xiaoning, born in 1957, is currently a professor and a PhD candidate supervisor at School of Mechanical Engineering, Nanjing University of Science and Technology, China. He received his PhD degree from Harbin Institute of Technology, China, in 1989. His research interests include pneumatic components, pneumatic transmission and control, etc.

KAGAWA Toshiharu, born in 1950, is currently a professor and a PhD candidate supervisor at Tokyo Institute of Technology, Japan. He received his PhD degree from Tokyo Institute of Technology, Japan. His research interests include fluid dynamics, fluid measurement and control, etc.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Guo, Z., Li, X. & Kagawa, T. Sewerage force adjustment technology for energy conservation in vacuum sanitation systems. Chin. J. Mech. Eng. 26, 334–340 (2013). https://doi.org/10.3901/CJME.2013.02.334

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.3901/CJME.2013.02.334

Key words

Search

Navigation