Using municipal solid waste incinerator fly ashes in the production of calcium silicate hydrate materials and the examination of chloride stabilization

Abstract

The fly ash produced by the municipal solid waste incinerator (MSWI) contains a large amount of common cement elements such as calcium and silicone so it can be used to produce hydrated calcium silicate materials replacing calcium and silicon sources in the production process However due to the large amount of chlorides and sulfates it may cause corrosion and durability problems to cement products and as a result the recycling route is limited In order to reduce the problem stabilizing chloride and sulfate is essential Studies have shown that Friedel's salt is one of the few stable chlorinated minerals in nature (Forano 2004) and the production of Friedel's slats by modified fly ash can reduce corrosion problems If the interaction mechanism between Friedel salt in the calcium silicate hydrated material and chloride and sulfate can be clarified it can promote the application of the technology of using incinerator fly ash to produce calcium silicate hydrate materials and further relieve the urge of graduate saturating landfills nowadays This research has three objectives: (1) Find out the appropriate ratio of SiO2 Ca(OH)2 and cement to produce hydrated calcium silicate material; (2) Use municipal waste incineration fly ash to produce hydrated calcium silicate material and explore the potential of MSWI fly ash as a hydrated calcium silicate material; (3) Find out the stability of heavy metals chlorides and sulfates in the calcium silicate hydrate material produced by MSWI fly ash and add sodium chlorate to form Friedel's salt and explore its stabilizing effect on chloride salts

Date of Award	2020
Original language	English
Supervisor	Juu-En Chang (Supervisor)