The use of heavy oil with much sulphur for burnning portland cement clinker is less expensive. SO₂ and SO₃ in the exaust gas is afraid to bring about the air pollution, however, these compounds will completely be caught by raw material of portland cement in suspension preheater which has recently been developed. Portland cement with much sulphur is interested in the character as expansive material.
In present paper, the authors prepared portland cement clinker fit for the two advantageous attempts and studied the properties. Initially, various amounts of gypsum, such as 2, 5, 10, 20, and 30%, are added to powdered commercial portland cement clinker as base material. The pelletized mixtures are burned at 1450°C, for 30 minutes in electric resistance furnace. Since a part of SO₃ leaves the clinker during the burnning, the SO₃ content in burned clinker is usually less than that given before the burnning. The fusion temperature of clinker go down with increasing the content of SO₃.
The polished section of over-burned clinker with much sulphur shows the formation of large-grown crystal of alite. The bending and compressive strength of mortar made from these powdered clinkers shows maximum values in the range of 3% to 6% of the content of SO₃. The values are larger than that of a commercial portland cement used for comparing with the present clinkers with SO₃. Only the clinkers with SO₃ content over 6% have expansive effect in the length change in water and in air with R. H. 53%.
Of clinkers made by burnning without fusion, the bending and compressive strength of clinkers with SO₃ content in the range of 3% to 6% is similar to that of clinkers burned at 1450°C. But, the clinkers with the SO₃ content over 6% burned under 1300°C, which have ill-grown alite crystal on account of incomplete burnning, are lacking in the development of strength.

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A method to utilize the soluble MgO in the calcined serpentine as magnesium ammonium phosphate fertilizers was studied.
Serpentine of table I which were taken at Yoshikawa in Aichi prefecture was calcined at 710°C, 2 hrs.
These calcined serpentine were treated with 5% solutions of (NH₄) ₂HPO₄ and NH₄H₂PO₄ at their boiling point, and the fertilizer were separated according to the scheme of Fig. 6.
The citric acid and water soluble MgO, P₂O₅ and N of the fertilizers was analysed by usual methods. And we obtained following results as shown in Table II and III.
By treatment with (NH₄) ₂HPO₄ solution “extracted ppt” of 40-20% and “extracted residue” of 150 - 107%, containing total fertilization of 42-79% and 23-15% respectively were yielded.
By treatment with NH₄ H₂PO₄ solution “ppt” of 53% and “residue” of 86%, each containing 57% and 14% fertilization were yielded.
If these ppt and residue were filtered at same time, the manufacturing process become easy. And the former treatment yield fertilzer of 127% and the later 138%, each fertilizer contains 27% and 26% fertilizer effect respectively.

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