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This paper involves the preparation technologies of cold bonded pellets for direct reduction using an organic binder-Funa. Investigation shows that the binder possesses excellent adhesive abilities to iron ore concentrates and is the key to the preparation of cold bonded pellets. Pretreatment on the binder-bearing iron concentrates prior to balling operation is essential to the maximization of adhesion of the binder to ore particles. Roll drum milling was found to be an effective method for the purpose. Investigation also shows that iron ore concentrate containing the organic binder has a lower balling kinetics than bentonite concentrate due to the increased viscosity by the binder. A balling time of 20 min is needed to ensure the pellet strength. It is found that the appropriate drying and hardening conditions for wet balls are 200-250°C of temperature and 0.8-1.0 m/s of airflow rate. TGA and DTA detection shows that the organic binder is thermally stable below 250°C in either neutral or oxidative atmosphere. Under above conditions, cold bonded pellets with a compressive strength of 250-300 N/Pellet, a drop strength of 7-10 times/1.0 m and a resistance to abrasion over 98 % (ϩ3 mm) have been attained from magnetite concentrates by using 1.5 % of the organic binder. Tests show that the cold bonded pellets present a greater reduction rate and a higher iron grade of products than fired pellets made with bentonite as binder.KEY WORDS: iron ore; pelletization; binder; cold bonded pellet; direct reduction.tions and properties of wet and dry pellets.(1) Viscosity A Stormer viscometer was used to measure the viscosity of binder solutions. It consists of two concentric cylinders, the inner of which rotates while the outer is held stationary. Viscosity is determined by measuring the rate of rotation of the inner cylinder under the application of a known torque. The solution was prepared by fully dissolving binders in water followed by centrifugal separation of impurities.(2) Compression StrengthsTo measure the compression strength of a ball, it is subjected to uniform loading between two parallel plates until the ball is ruptured. A total of 20 balls with the average diameter of 12 mm for wet balls and 11 mm for dry balls are measured. The average of compressions at which the balls break down is measured in N as the compression strength. (3) Drop StrengthsThe drop strength is measured by means of letting a ball hit a steel plate repeatedly from a height of 0.5 m for wet ball and 1.0 m for dry ball. The numbers of drops the ball is able to withstand without damage is measured as the drop strength of the ball. A total of 20 balls with the average diameter of 12 mm for wet balls and 11 mm for dry balls are tested. The average value of the drop number is used as the drop strength. (4) Resistance to Heat ShockThe resistance to heat shock is expressed as a temperature at which 90 % of the balls remains undamaged. The test is made on 20 green balls, which are placed in a preheated furnace. The residence time in the furnace is 1...