Hi & Welcome to Linux Questions.
What distribution you are running?
Is this your Lenovo?
I am not the expert with the ACPI stuff but I've dealt with some of the acpi stuff in the past.
***It might be possible to disable the sleep or hibernate in the BIOS but I suggest you wait for a experienced member for that.***
Looking at the XFCE Power Manager on my system I see that the line for suspend and hibernation say's:
"When hibernate button is pressed
a drop down menu opens and there are 4 options.
nothing, suspend, hibernate or ask
Try setting it to nothing.
The same options are available for the sleep button:-
Advanced Configuration and Power Interface provides a standard for device configuration and power management.
Like the fan on your motherboard for example at start up is part of the ACPI stuff.
XFCE Power Management manages the power sources on the pc and the devices that can be controlled to reduce
power consumption ie
LCD brightness level, monitor, sleep and CPU frequency scaling.
It provides the interface which allows applications to prevent automatic sleep actions via the Power Manager.
Hope that helps.