This research aims to develop the concrete blocks mixed with cassava pit waste. There are 6 mixing ratios among Portland cement type1: rice hush ash: quarry dust: cassava pit waste: water reducer type A: tap water that include 0.7: 0.3: 10: 0: 0.02: 0.6 0.7: 0.3: 9.9: 0.1: 0.02: 0.6 0.7: 0.3: 9.7: 0.3: 0.02: 0.6 0.7: 0.3: 9.4: 0.6: 0.02: 0.6 0.7: 0.3: 9.1: 0.9: 0.02: 0.6 and 0.7: 0.3: 8.8: 1.2: 0.02: 0.6 by weight. The concrete block samples were casted same as the ordinary concrete blocks and test were conducted according to TIS.57-1990 standard. From the results the best proportion of concrete block mixed with coconut shell ash is 0.7: 0.3: 9.7: 0.3: 0.02: 0.6. The proper ratios of cassava pit waste can decrease the density or weight and increase the thermal insulation of concrete blocks. However the over amounts of cassava pit waste that effected to increase the water absorption and decrease the compressive strength properties of concrete blocks.

The objective of study was to design and development of spray drying technology for production of salt powder. The process design and build spray dryer that consisted of three parts: an atomizer a drying column and a dry powder collecting unit. The operation of a spray dryer was co-current flow. A drying column had diameter 0.5 m high 1.5 m and heater 15 kW with automatic temperature control PID 220 V AC power. The test used a saline solution. The inlet air temperature had 5 levels: 130 140 150 160 and 170 ?C. The inlet air velocity had 5 levels: 8 8.5 9 9.5 and 10 m/s. The results were a spray dryer be able to saline solution became salt powder with moisture content between 1.0 - 2.5 % (wet basis) which was in the standard of pure consumable salt (TIS 2086-2544) and can be classified at first class that moisture content had no more than 3 %