TOCICO

This presentation describes the use of the TOC concept of continuous flow and 6 sigma in improving throughput at the Dead Sea Works, a manufacturer of potash (a chemical to improve yield in all plants) located in Sodom, Israel. The basic flow was from Dead Sea water to evaporating ponds to a raw material plant to processing plants to white, red and granulated potash. The objectives of the project were to significantly and quickly increase the throughput of potash production at the Dead Sea Works. An example of a two station line with dependencies and statistical fluctuations is provided. System output is defined by the slower station. Output of the system is the minimum of the two stations. The two station example is again used with equal capacity but very different variability. The results are even more restrictive: average loss is still about 1/3 of the standard deviation of the large variable; the loss is mainly dependent on the variable, which has the larger standard deviation, and almost not on the small one, till we reach the point where the relative quantitative relations between them is reversing; standard deviation is declining even more; the lost is relative to the fluctuations of the resources; etc. A numerical simulation proved the same basic relationships as the mathematical enumeration. The capacity of the first station was increased and numerical simulation was used to calculate the expected throughput of the system. The incremental investment and profit were computed for expanding station 1. Changes were made to the actual production facilities and the significant throughput increases were realized. The experiments showed that a loss in a bottleneck is proportional to the variability of the stations, especially the large one. That is why decreasing the variations by statistical process control (SPC)—be it lean, kaizen or 6 sigma methods-might bring about additional increases of production.