Ethanol is used in millions of mowers every year...
alcohol is used to raise the octane, if it evaporates or you remove it, you are left with poor fuel. Alcohol will blend with water, gasoline will not, if you remove the alcohol or if it evaporates out, you will have the water left... in the poor fuel... If you take the poor, low octane fuel of the top of the water mixture on the bottom ... you are not going to have good fuel...
Get fresh ethanol gasoline and use it as you need it... try to not have old fuel and you should have minimal fuel problems...