A non-sintered high-strength lightweight aggregate one-shot prepared from sulfur-based and alkaline-based solid wastes by stirring, granulation, and foaming, and a preparation method therefor and use thereof. The non-sintered high-strength lightweight aggregate is prepared from a sulfur-based solid waste, an alkaline-based solid waste, an auxiliary cementing material, a ferro-aluminum-sulfur cementing material, water, and a foaming agent as raw materials. Based on the mass of the total solid, the total content of the sulfur-based solid waste, the alkaline-based solid waste, and the auxiliary cementing material is 80-90 wt %, and the content of the ferro-aluminum-sulfur cementing material is 10-20 wt %. The mass ratio of the water to the total solid is (15-20):(80-85). The foaming agent accounts for 0.3-0.7% of the mass of the total solid. The mass ratio between the sulfur-based solid waste, the alkaline-based solid waste, and the auxiliary cementing material is (27-33):(27-33):(18-25).

The invention provides a method for producing lightweight concrete mixtures using lightweight aggregates, comprising an at least two-stage mixing process, where first a suspension mixture comprising the binder composition is prepared by high-speed stirring with a cement or a geopolymer and water and then the suspension mixture is mixed by low-speed stirring with constituents including the lightweight aggregates. The invention also embraces lightweight concretes and lightweight concrete mixtures produced accordingly. Binder composition candidates include, for example: 60-80 wt % finely ground slag sand cement, 10-60 wt % fly ash2-25 wt % alkali metal hydroxides/alkali metal silicates, 75-98 wt % finely ground slag sand2-20 wt % alkali metal hydroxides/alkali metal silicates, 60-78 wt % finely ground slag sand20-38 wt % fly ash cement, 30-50 kg/m (in the lightweight concrete mixture) microsilica cement, 10-60 wt % rice husk fly ash cement, 1-5 wt % caustic calcined CaO/MgO

The present invention relates to a process for producing calcium silicate hydrate under hydrothermal conditions, wherein an organic compound is added in at least one of the process steps and wherein the organic compound has a molecular weight of 100 to 600 g/mol and from 0.02 to 0.035 functional groups per gram of the organic compound, wherein the functional groups being selected from OH, COOH, COOM.sub.a, SO.sub.3H or SO.sub.3M.sub.a, or C(O)H, wherein M is hydrogen, a mono-, di- or trivalent metal cation, ammonium ion or an organic amine radical and a is , or 1. Further the invention is directed to the calcium silicate hydrate produceable according to the process of the present invention and its use as curing accelerator for hydraulic binders.