In low permeability reservoirs, hydraulic fracturing treatments are usually utilized to evaluate reserve quality in exploration wells or make producing wells economically. As we all know that the formation damage during a hydraulic fracturing job may reduce a well's production rate in a large degree, so, a new comprehensive hydraulic fracturing technology aiming to minimize formation damage is put forward in the paper. Compared with the past common hydraulic fracturing technology, it mainly contains 7 sections:1)the optimization of PAD volume;2)the optimization of polymer concentration used in fracturing fluid;3)the technology of high sand concentration and the optimized proppant pumping schedule(more than 10 stages) correspondingly;4)the optimization of pumping rate and increasing pumping rate step by step during last stages of proppant pumping;5)fracturing fluid additives selection and the optimization of breaker schedule;6)forced closure technique is performed at the moment of shut-in;7)the control of bottomhole flowing pressure during flow back of fracturing fluid and production stage in the case of stress sensitivity which is usually a main characteristic of low permeability reservoirs. After the study, four exploration wells belonged to a certain oil field of petrochina are hydraulically fractured using above technology system. The well A1 and A2 get an idea post-fracturing rate of 9.12m3/d and 11.44m3/d respectively, compared with 1.94 m3/d of their adjacent well A7. what's more, a new geology reserve has been determined up to 5,000,000 tons as a result of above 2 successfully fracturing treatment wells. Similarly, the well A5 get a rate of 16.82 m3/d compared with 0.78 m3/d of its adjacent well A6, and the well A3 get 30.57 m3/d compared with 25.7 m3/d of its adjacent well A4. Overall, the comprehensive hydraulic fracturing technology put forward in the paper has a great significance in evaluating reserve quality, sometimes it may even be used to find an undiscovered reserve. On the other hand, it may also increase economic benefit of a producing well in low permeability reservoirs.

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