Can we take benefit Duty Draw back & Depb both

Dear Sir,

Can we take benefit both secheme duty draw back and depb. we have excess credit our excise duty rate 4% and 25% Export , input credit 8%. we claim excise duty under rebate claim of duty. Still we have more credit. if we can take duty draw back then it can be reduce because input rate of duty 8% and 4% additional duty. Please tell me am i right or wrong. Can it is possible or any other alternative. Thanks