MCD to determine calorific value of waste collected

New Delhi: Municipal Corporation of Delhi (MCD) has prepared a draft plan for the characterisation of waste collected from 12 zones and quantifying its calorific value. This will help authorities plan and engage the processing facilities according to the different variety and quantity of material recovered.
Waste characterisation is the process of collecting and analysing information about the quantity and composition of solid waste.This information is gathered by taking samples of waste from different areas, sorting them by material type, and weighing each type.
The last study was done by the erstwhile south corporation in 2017-18 through Shriram Institute of Industrial Research. "Samples were collected from various wards in four zones, including central, south, west and Najafgarh, to ascertain the amount of wet waste, metal, electronic waste, inert, etc., disposed of by residents," said an official.
The report stated that 30% of the total waste constituted green waste, around 16% inert, 15% stone, 12% plastic material, 10% paper and 9% textile. The rest of the material recovered included glass, rubber, wood, coconut and food waste. Based on the samples collected, it was also concluded that the highest calorific value of waste collected was 1,354 and the lower calorific value was 1,264.
"The calorific value usually means the amount of energy which can be generated when the waste is incinerated in a waste-to-energy plant. The fresh study of waste is required to ascertain the current calorific value of waste and design our equipment accordingly," said an official. Further, in the study, the percentage of moisture found in waste collected from households was 46.5%. "This thing also needs to be studied freshly so that we will know in advance how much heating this waste will require to take out all moisture before it is sent to the waste-to-energy plant or used for any other purposes," said the official. Currently, Delhi generates 11,300 MT of waste every day. Despite the Municipal Solid Waste bylaws of 2019 emphasising 100% waste segregation at source, only 353 selected colonies are adhering to the norms, as per a DPCC report issued early this year.
Experts say with the limited number of decentralised centres, fixed compacting stations and material recovery facilities, it is not feasible to segregate and process the entire waste generated.
Consequently, mixed waste amounting to 7,400 MT is sent to four WTE plants, while the remaining unprocessed waste ends up at landfills.