Application Number: 201911040875

Filing Date: 9 October 2019

Inventors: Dr. Biswajit Ruj Dr. Swarup Ranjan Debbarma

Other Inventors: Sankha Charabortty, Pretam Kumar Mondal

Abstract:

Managing of arsenic and iron-rich sludge generated from different arsenic-iron water treatment plants is a main issue of great concern in several developing countries. Due to limited options for disposal of highly concentrated arsenic rejects, many arsenic removal plants generally dump the rejects into the environment which leaves potential risk of recontamination of underground aquifers or surface water through natural percolation process. Moreover, generation of high volume iron-rich sludge increases sharply inviting further problems in transportation and make crises of fresh land in the environment. A possible solution to this disposal problem may be traced in stabilization of arsenic in some solid matrix, such as concrete in which natural fine aggregates (river-sand) have been replaced by arsenic and iron contaminated sludge mixed sand. To make three different grade (M15, M20 and M25) of concrete blocks, arsenic and iron sludge have been taken with a density of 425 to 535 kg/m3 with a mixing ratio of 1: 10 (arsenic: iron) followed by mixing of designed quantity cement, coarse aggregates, water and additives. Successful TCLP and test for compressive strength of the sludge-fixed concrete cubes classified it as a non-hazardous value added materials. This process involve stabilization of arsenic-rich sludge generated from water treatment plants with the successfully replacement of fine aggregates in concrete mix with some other waste materials like iron sludge mixed sand renders itself a sustainable novel non-chemical route of stabilization towards reutilization.

Patent Type: Filed

Place of Patent: India