Leachability of Immobilize Hydrocarbon Waste in Zeolite Cement

Currently, over 80% of hazardous wastes are from industrial processes and that includes hydrocarbon waste. Hydrocarbon (HC) wastes are complex substances consisting of free oil, oily sludge, solvents, emulsified oil, solids, and water that can either originate from crude oil stock or processed streams. Hydrocarbon waste is highly volatile and is dangerous to the environment. Therefor the solidification/stabilization (S/S) technology is applied in the treating of hydrocarbon waste to observe its capability in treating hydrocarbon waste. The scope of the research covers waste which consists a high amount of hydrocarbon residue from the petroleum refinery in Kerteh, Terenggannu. The case study of this project is to obtain the best mixture ratio of cement to water (C/W) ratio, cement to sludge (C/S) ratio and cement to zeolite binder (C/B) ratio by testing its compressive strength and also study the effects of zeolite on the porosity, permeability, leachability and total oil and grease content of the immobilized hydrocarbon, (HC) waste in the cement. The technology of solidification and stabilization must prevent uncontrolled releasing of bounded harmful components in immobilize hydrocarbon waste into the environment even under conditions of long exposure to the action of possible agents such as atmospheric conditions and other aqueous electrolytes. The quantities of harmful components released into the environment through the rinsing processes must not exceed the quantities allowed by standards and rules on taking care of harmful wastes is discussed in this report. The main results obtain were the compressive strength test of the cement which met USEPA standards for construction purposes. The highest compressive strength with admixture zeolite is 31 MPa with 10% zeolite composition and 40% sludge content in mixture. In addition the metal content and total oil and grease content of the cement mixture after leaching is well below the allowable standard which is the target. For TOG the reduction of concentration is from 36 ppm to 3 ppm, which is an approximate of 90% reduction of TOG content in the leachate compared to raw sludge. Furthermore the metal content in the leachate obtained are all under 1ppm. Zeolite is a natural occurring element and not harmful to the environment, therefor using it in the case study is well in line with the universities target to create a greener alternative in its inventions.