This paper concerns the process of production and properties of pellets based on biomass wastes. Co-pelletization was performed for sewage sludge from municipal wastewater treatment plant and other biomass material such as animal and olive wastes.

The aim of the present study was to identify the key factors affecting on the sewage sludge and agricultural residues co-pelletization processes conditions. The impact of raw material type, pellet length, moisture content and particle size on the physical properties was investigated. The technic and technological aspects of co-pelletization were discussed in detail.

The physical parameters of pellets, i.e.: drop strength, absorbability and water resistance were determined. Among others, also energy parameters: low and high heat value, content of ash and volatiles were presented.

Results showed the range of raw materials moisture, which is necessary to obtain good quality biofuels and also ratio of sewage sludge in pelletizing materials.

The analysis of the energetic properties has indicated that the pellet generated on the basis of the sewage sludge and another biomass materials can be applied in the processes of co-combustion with coal. Those biofuels are characterised with properties making them suitable for use in thermal processes and enabling their transport and storage.

本文涉及基于生物质废物的颗粒的生产过程和性质。对市政污水处理厂的污水污泥和其他生物质材料（如动物和橄榄废料）进行了共粒化。

本研究的目的是确定影响污水污泥和农业残渣共制粒工艺条件的关键因素。研究了原料类型，颗粒长度，水分含量和粒径对物理性能的影响。共同制粒的技术和工艺方面进行了详细讨论。

测定粒料的物理参数，即：下落强度，吸收性和耐水性。除其他外，还提出了能源参数：低和高热值，灰分和挥发物含量。

结果显示了原料水分的范围，这是获得优质生物燃料所必需的，还包括制粒材料中污水污泥的比例。

对能量性质的分析表明，在污水污泥和另一种生物质材料的基础上产生的颗粒可用于与煤共燃烧的过程。这些生物燃料的特点是使其适合用于热过程，并使其能够运输和存储。