Underline the correct item. 1) is ruth yours / your sister? 2) tina and susan are my / mine friends.

To understand how paper is made, you must first determine its type, because the composition of the raw materials can be different. The main material in the paper industry is wood. Whole shafts are delivered to the mills. There they remove the bark, cut it. Then the raw materials are ground into flour - to fibril fibers. The technology consists of the following stages:

mass treatment - grinding, dyeing, mixing plant and chemical components;

dilution of the mass with water, purification, pressing and drying;

calendaring;

cutting, sorting and packaging. The paper manufacturing process begins with the grinding of raw materials in continuously operating machines. The factories use rolls, conical and disk type mills, refiners. The paper manufacturing process begins with the grinding of raw materials in continuously operating machines