UPSC Prelims 2015·GS1·science-and-technology·science and technology

With reference to bio-toilets used by the Indian Railways, consider the following statements: 1. The decomposition of human waste in the bio-toilets is initiated by a fungal inoculum. 2. Ammonia and water vapour are the only end products in this decomposition which are released into the atmosphere. Which of the statements given above is/are correct?

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  1. A1 only
  2. B2 only
  3. CBoth 1 and 2
  4. DNeither 1 nor 2Correct

Explanation

Let's analyze the statements regarding bio-toilets used by Indian Railways: 1. The decomposition of human waste in the bio-toilets is initiated by a fungal inoculum: This statement is incorrect. The decomposition in the bio-digester tanks of Indian Railways' bio-toilets is primarily carried out by a consortium of anaerobic bacteria, not fungi. These bacteria convert human waste into biogas and treated water. 2. Ammonia and water vapour are the only end products in this decomposition which are released into the atmosphere: This statement is incorrect. The primary gaseous end product of the anaerobic digestion process is biogas, which mainly consists of methane (CH4) and carbon dioxide (CO2). Treated water is also produced, which is discharged. While some amount of ammonia might be present, it's not the primary gaseous product, nor are ammonia and water vapor the *only* end products released. The main goal is to prevent raw human waste from being discharged onto the tracks and convert it into less harmful byproducts. Since both statements are incorrect, the answer is neither 1 nor 2.
science-and-technology: With reference to bio-toilets used by the Indian Railways, consider the following statements: 1. The decomposition of hu

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