a delivery system for delivering drilling fluid additives to a drilling fluid . according to one aspect of the invention , the delivery system comprises a softened , dispersible tablet containing drilling fluid additives , such as lost circulation , seepage control materials , and / or other additive materials . the tablet is preferably prepared by adding a softening agent or softening binder to the drilling fluid additive that will allow the tablet to disperse and revert , or break down , to release the drilling fluid additives in their original particle size into drilling fluids . it is also advantageous for the tablets to be dispersed top - side to ensure that the materials do not , for example , clog screens or damage downhole equipment .