Carbide Slag as Raw Material

Carbide slag, also known as calcium carbide residue (CCR), is a by-product of the hydrolysis of calcium carbide. It is commonly generated from the industrial production of ethylene, polyvinyl chloride (PVC) and other products as a solid waste. Currently, it has no value for recovery and is commonly landfilled. At some Chinese plants, this slag is used as an alternative raw material for cement production, making up to 68% of the raw kiln meal by mass. Use of CCR requires its pretreatment by drying and grinding, after which it is mixed with the rest of the raw materials and follows a conventional process flow.

Indian flag In the Indian context, there is a need to establish the availability of this material.  In the country only one plant is reported to be using this alternative material. 

Development Status Products
Commercial
clinker, Cement

Carbide Slag as Raw MaterialCosts & Benefits

Parent Process: Alternative Raw Materials
Energy Savings Potential

Not available

CO2 Emission Reduction Potential

In a Chinese project, 184 thousand tons of CO2 reduction was forseen with the use of 315 thousand t/y of carbide slag and thereby substituting 432 thousand t/y of limestone. 

Costs

Total investments for utilizing 315 thousand t/y carbide slag was approximatly RMB 29.4 million (US $4.3 million [with 1RMB=US $0.146])

Carbide Slag as Raw MaterialSchematic

Carbide Slag as Raw Material Reference Documents

Clean Development Mechanism - Project Design Document for Nanning Shizuo Non-Carbonated Raw Material for Cement Production Renovation Project

The document provides the details of a project developed under UNFCC's Clean Development Mechanism, that involves the use of Carbide Slag in a cement plant in Naning City Guangxi Zhuangzu Province in China. 

Page Number: 

2, 6, 11