Investigation of the use of calcium naphthalene sulfonate as a binder in magnesite spinel brick production and determination of optimum conditions

Refractory materials are indispensable for industries working with high temperatures. Magnesite spinel refractory bricks are used in the cement industry, and calcium lignosulfonate is used as a binder in their production. Due to forest fires and similar reasons in recent years, there is a problem in the supply of calcium lignosulfonate raw materials. In this study, research was conducted on alternative binders to be used in the production of magnesite spinel bricks and the optimum conditions for production with the selected binder were determined. Some of the binders are calcium naphthalene sulfonate, sodium naphthalene sulfonate, magnesium oxide, magnesium sulfate, and molasses. As a result of preliminary tests, it was observed that the most successful results were obtained with calcium naphthalene sulfonate. The optimum conditions for produce of magnesite spinel refractory bricks using calcium naphthalene sulfonate were found by the Taguchi method. As parameters, seawater sintered magnesite in 4 different fractions (A: 3-5 mm, B: 1-3 mm, C: 0-1 mm and D: Powder) and Sinter Spinel in 2 different fractions (E: 3-5 mm and F: 1-3 mm) in total, 6 parameters were selected, and an L16 (44x22) Taguchi orthogonal array design was created for this. Volume weight, water absorption, porosity, and strength tests were performed on the samples obtained. Accordingly, considering the strength values, the optimum conditions were determined as A1, B1, C2, D4, E1 and F2. Under these conditions, the estimated strength value was calculated as 84.24 N/mm2 and the experimental value was 83.85 N/mm2.