SHANGHAI Petrochemical Co has registered a 168 per cent rise in profit to 573.89 million yuan (about HK$769.01 million at the official rate) for the six months ended June 30. The strong growth was attributed to improved production efficiency and higher sales. Turnover jumped 90.8 per cent to 4.65 billion yuan. Earnings per share were 14.3 fen, up from 5.3 fen. The half-year earnings represent about 67.7 per cent of the forecast profit of 848.3 million yuan for the full year ending December 31 as set out in the prospectus for the H-share issue in July. As stated in the prospectus, the directors will pay a special interim dividend of five fen per share, absorbing a total of 200 million yuan, to China Petrochemical Corp, the sole shareholder before the company went public. ''Following an encouraging first half of the year, the board of directors is determined to continue its efforts to expand the company's operations,'' said Wang Jiming, president of Shanghai Petrochemical. ''The supply of crude oil is expected to remain stable in the coming six months and major maintenance programmes, launched in August and October, will assist the company to achieve high utilisation rates in all of its production units for the remainder of this year and into 1994,'' he said. Mr Wang said demand would continue to be strong and prices firm. Barring unforeseen circumstances and subject to the assumptions made in the prospectus, the group expected to achieve its forecast profit for the full year, he said. The volume of processed crude oil grew by 35.81 per cent to 2.46 million tons, which led to a strong performance in the output of related petroleum products. Driven by China's economic expansion, the company said demand for its products continued to exceed levels of supply. Sales as a percentage of total production for the six months averaged 99.85 per cent, and peaked at 100.88 per cent and 105.71 per cent in May and June, respectively. ''Demand for petrochemical products from other industrial sectors has grown faster than the economy as a whole, and should continue to do so in the foreseeable future,'' the company said.