Performance Affecting Parameters of a Waste Composting Machine


Waste management has become a serious environmental issue all over the world in the past few years. Most of the urban areas are facing this and biogas. Adequate temperature and humidity may increase the conversion efficiency of a waste composting problem. It is observed that people residing in these areas are highly suffering from respiratory diseases in comparison to other areas. Proper management of waste material is the only solution to the problem. The method used for managing waste is called composting. It is the process in which waste material on heating produces biological products like fertilizers machine. This paper includes a study of various parameters affecting the performance of composting machines. The purpose is to make an eco-friendly atmosphere with minimum hazardous wastes.


The world is suffering from many environmental issues in the era of the 21st century. Most of the civilized countries are suffering from the adverse effects of the environment. One of the serious issues in this regard is the increasing amount of waste material and its decomposition. About 10 million ton of waste material is generated only in the metropolitan cities of India. Per person produces about 300-400gm solid waste in India. India is the third highest waste generator in the world. The seriousness of the problem lies where out of total garbage collected by municipal corporations only 5% is composted. Recycling and reuse is the only option to minimize waste material. Most of the organic wastes contain 80% of water which needs to be converted into steam for its proper utilization. The most efficient waste composting plant is one which extracts maximum possible benefits from the byproducts of garbage material and thus generating minimum waste.

Waste Composition of India, in Million Metric Tonnes per annum. Source: PIB 2016
Fig.1 Waste Composition of India, in Million Metric Tonnes per annum. Source: PIB 2016

Figure-1 shows the report of PIB in the year 2016 which indicates the waste composition in India in Million Metric Tonnes per annum.

Components of the waste composting machine

A waste composting machine is composed of the following parts:

  1. A Drum- Drum of galvanized steel is generally used for incorporating all the waste material.
  2. A D.C. motor which provides power to run the machine. The motor is designed to run at a low speed generally from 3-6 RPM.
  3. Shredder- For the pulverization of available input waste. Here the waste material is mashed for further processing.
  4. Mixing Blade- For the proper mixing of waste material blades are used which converts the input into fine particles.
  5. Exhaust Vent- For the easy escape of gases vent is provided which helps in maintaining the exhaust of produced gases.
  6. Air heater- Air heater is provided for maintaining the proper temperature and humidity in the drum. It reduces the composting time.

Parameters affecting the composting efficiency

Various parameters affecting the performance of a waste composting machine are temperature, PH value, humidity, C/N ratio and aeration rate.

  1.  Temperature-Temperature is the most important factor in achieving higher efficiency of a waste composting machine. Adequate temperature provides proper metabolism and converts the waste material into various useful biological products.
  2. PH Value- PH value of the material being compost is one of the deciding factors for a composting machine. PH from 4.5 to 6 is best suited for composting materials since it ensures the best utilization of waste material.
  3. Humidity- Humidity present in the atmosphere of a composting machine is also an important factor in achieving higher efficiency of composting machine. Dissolved gases and nutrients are transferred to the cell membrane of microorganisms at the proper humidity.
  4. C/N Ratio- The ratio of carbon and nitrogen gases available in the composting material is one of the important factors for better utilization of waste material. Since nitrogen provides proper nutrients to the biological products, it must be in a sufficient amount.
  5. Rate of aeration- Proper aeration rate is important for high efficiency of composting machine. Air provides oxygen for the decomposition of bio-products. It is also useful for maintaining proper humidity in the composting machine. Air takes away the exhaust gases and heat produced during the process. Hence proper aeration rate is important.


Review article provides the scope of research for scholars to work on the various parameters affecting the efficiency of a composting machine and prepare such a model which best suits for achieving the highest composting efficiency. The major factors which play important role in the best design of a composting machine are temperature, humidity, C/N ratio, aeration rate and PH value of the composting waste. Sufficient temperature provides better conditions for the decomposition of waste material into useful biological products. PH value of compost material utilizes the waste material properly. Adequate aeration rate is important to take away the heat and gases produced up to the exhaust. Nitrogen produced in the air and exhaust gases provides the best conditions for growing biological plants.