When hydrocarbons are produced from a reservoir, solid particles sometimes follow the reservoir fluid into the well. This unintended byproduct of the hydrocarbon production is called solids production.

The amount of solids produced can vary from a few grams per cubic metre of reservoir fluid, which usually represents a minor problem, to catastrophic amounts possibly leading to complete filling of the borehole. It is estimated that seventy percent of the world s hydrocarbon reserves are contained in reservoirs where solids production is likely to become a problem at some point in time. The problem is most pronounced in sand reservoirs, hence sand production has attracted most attention. However, it may also be a problem in chalk and coal reservoirs.

There is a large variation in the way solids production has been handled from not considering it as a problem at all, to not accepting anything but insignificant amounts of solids. The latter attitude has been spurred by the observation that sand production may result in serious accidents. However, methods to control solids production involves additional costs and usually results in reduced production, so that in later years a more relaxed tolerance for solids production is sometimes considered. When dealing with heavy oil, solids production is even deliberately provoked in some cases.

We shall here first take a look at some operational aspects related to solids production. Mechanisms that may cause sand production are then described, followed by discussions on how to predict sand production. Chalk production is discussed more briefly which reflects...