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The object of this study was the degradation of polycaprolactone films in a living composting environment with plant treatment active sludge. The incubation of polymer samples took place in the compost for a period up to 3 months. There are presented the characteristic parameters of plant treatment active sludge: temperature, pH, dry mass and activity of dehydrogenesis and their influence on degradation of polycaprolactone is discussed. The changes of weight, tensile strength, microhardness and morphology during experiment were tested. Enzymatic activity is resulted in surface erosion. Microscopical observations show deterioration of polycaprolactone surface. Hydrolysis (“bulk process”) is also contributed (onset of weight loss). The decreasing of weight and mechanical properties are observed after each period of incubation. The increase in the microhardness during first period of biodegradation can be directly proportional to the increase in crystallinity, because amorphous regions are degraded first what is confirmed by microscopical observation. The complete degradation of polycaprolactone in compost with plant treatment active sludge in living environment takes place after short period of time (3 month).

Abstract. The Wastewater Treatment Plant (WWTP) 'Swarzewo' plays a special role in the protection of coastal waters of the Baltic Sea area and the management of solid wastes in the region. This paper discusses several options implemented in the WWTP area in order to achieve sustainability. The first one was the inclusion of WWTP into municipal waste management plan to increase the biogas production and to reduce volume of organic waste in the region. Nowadays, daily production of about 2000 m 3 of biogas is gained. The energy balance shows a considerable benefit from the co-fermentation of sludge with municipal organic wastes. The next goal was to obtain a favorable economical balance of energy and high level of pollution reduction. The last one was the involvement of local communities in a conscious segregation of waste 'at source'. For the purpose of this paper bio-energy production, nutrient elimination, composting, and research, have been selected as indicators of sustainable development. Furthermore, in this study the methods of nutrient recovery from wastewater were explored. Struvite precipitation and compost production were presented as an example of nutrient elimination with 'end of waste' production. Depending on the struvite precipitation conditions, recovery of 4 Mg of phosphorous and 1,8 Mg of nitrogen is possible to obtain annually.

An important source of microplastics (MPs) in the Baltic Sea waters is plastic waste, which is fragmented in the natural environment. The pilot research on the identification of microplastics in the surface waters of the Port of Gdynia is presented. In this paper, microplastics of particle sizes 0.3–5 mm in harbour seawaters were investigated. Microplastics were collected from five harbour basins using an unmanned mobile research unit, HydroDron-1. Sampling of microplastics on the surface port water was conducted over four seasons. The collected plastic particles were separated by chemical oxidation and flotation in the NaCl solution (density 1.2 g/cm3). Polymer identification was carried out by visual and microscopic observations, as well as using the Total Reflection Fourier Transform Infrared spectroscopy. Based on tows conducted in five basins of the Port of Gdynia, in total, the concentration of microplastics identified ranged from 0.082 mg/m3 to 0.524 mg/m3, depending on the investigated basin. Four groups of microplastic shapes (fragments, films, fibres and spheres) were detected in all the investigated harbour basins. Fragments and fibres were prevalent when categorised by particle shape, whereas when categorised by colour, transparent, white and black particles were dominant. The predominant type of the identified polymers was polyolefins (PE, PP, PS) and their derivatives.

Poly(n-butylisocyanates) were synthesized by anionic homopolymerization with the addition of sulfonate groups in the termination stage. Two types of functional polymers were obtained from different quantities of added 1,3-propanesultone (PrS). When a stoichiometric proportion of sultone is added, the reaction with poly(n-butylisocyanate) renders a mix of a nonfunctionalized (PBIC) and a telechelic polymer (PBICT). In the presence of an excess of PrS, the proportion of end-functionalized chains was higher, and a significant change in their thermal properties was observed. Polymers were characterized by FTIR and NMR, and measurements of intrinsic viscosity were made. Thermal degradation of the polymers was studied under nitrogen atmosphere for various heating rates. The kinetic parameters such as the activation energy and the reaction order were determined by using Ozawa's method. Thermal degradation analyses showed that the degradation processes depend strongly on the concentration of functional groups.