Plastic is one of the most universal materials used today. With a good future view, with new implementations and applications, it makes a lot of time to look at the production and management of the plastic materials. Plastic materials that have been used in our daily lives cause serious environmental problems. Millions of tons of these non-degradable plastics accumulate in the environment every year. The basic problem is that plastic is not naturally occurring in nature since containers are usually made of polyethylene terephthalate. This means that microorganisms do not have the ability to break it down to the current cycle. It takes hundreds of years for plastic containers to break down, not biologically but only degenerate into smaller and smaller pieces. Plastic breaks down into smaller pieces that become smaller and smaller until we cannot see them with the naked eye, mainly through heat and UV light. Although we cannot see them, they are still present and become part of our nature forever. Bioplastics is the plastic industry's tool to try to reduce these little pieces of our nature that will remain forever so that they do not grow more. With today's plastic packaging, which is said to be bioplastic, additives of, for example, cobalt and nickel, which are said to make it easier for the polymers to break down over time, have proven to be not as effective as they thought.
Polyhydroxyalkanoates (PHA) are polymers which are biodegradable as based on their composition have different physical properties. PHA is a family of natural polyesters synthesized from various microorganisms discovered in 1926. Once discovered, interest has been high due to their biodegradability and its production from renewable resources. The polymers can be described generally as production from microorganisms under controlled conditions, where they occur naturally in organisms that classify them as biopolymers. Some of these polymers are already industrially produced on a large scale today. However, many still apply to several new areas but must be optimized for commercial production.
Biopolymers can be classified into four groups. Amino-acid-based polysaccharides from bacteria, polyphenol-based and polyesters that this study is looking at. Depending on what the microorganisms possess for character traits and what they give to the substrate to break down, it gives polyesters with different physical properties. This case is a short-chain polyester to be formed, more specifically P3HB which is a three-carbon PHB polyester in its polymer which can be up to 5-7 units long.
To avoid ongoing problems, a solution is needed. A solution that has received much attention to reduce plastic residues in nature is the use of biodegradable plastics and among them polyhydroxyalkanoates. Polyhydroxyalkanoates (PHAs) are common intracellular compounds found in bacteria, archaea and in few eukaryotes such as yeast and fungi. PHA acts as an energy storage polymer that is produced in some microorganisms when the carbon source is abundant and other nutrients such as nitrogen, phosphorus, oxygen or sulfur are limited. These polymers accumulate intracellularly up to 90% of the dry weight of the cell under nutritional conditions and act as energy saving materials. It has resembled mechanical properties like the traditional oil-based plastic such as polypropylene or polyethylene that can be formed with other synthetic polymers. PHA plastics possess many more applications, in agriculture, packaging and in the medical industry. It is biodegradable and also immunologically compatible. What the PHAs plaster can cause is an ultimate decomposition from a non-fossil source, which is exactly why it is very attractive.
The purpose of this study was that from a hypothesis see within a limited time frame of ten hours of bio sludge from Gruvön, Skoghall and Bäckhammar's use could accumulate PHA with the aid of added readily degradable substrate. The process of the study will be a small part of a current research project together with Paper Province, Promiko, Pöyry and RISE. The aim of their study is to use residues from the forest industry to make hydrogen as well as bioplastics. This study will help to look at a subprocess of their cascading process.
The aim of the study is to be able to measure the amount of PHA that could accumulate and rank the potential of the different uses. Using chemical analysis methods and extractions, it will provide opportunities to measure the accumulation of PHA in the various bacterial cultures of biomass from the use. The methods involve soxhlet extraction to successfully extract PHA from the bacteria. Dosage of substrate is sodium acetate piped from egg-diluted solution at 600 mg per dosage. In order for the dosage to be added at the right time, DO and the pH of the reactors were measured and logged throughout the course. FT-IR is used to view the course of events during the experimental period, linked to known features that may indicate that PHA is present in the bio sludge. Nutrients like phosphorus and nitrogen are measured, along with SÄ, SS, TOC, several before and after the experiment to compile discussion of the results.
The conclusion was based on the analysis methods that the bio sludge that yielded the best yield was from Gruvöns use. This also relates best to the hypothesis of celebration and starvation, the relationship to which the bio sludge is exposed. The mine has a slurry in its five-step process which causes the bio sludge to return from step five where there is a shortage of food for bacteria to step three where there is a lot of food to consume. The rankings of the different uses relate to the hypothesis that the use of mining was best and the worst was the use of Bäckhammar. Based on the analysis methods included in the study, it can be concluded that the bio sludge that yielded the best yield was Gruvöns use with 13.6% of PHA / VS from the soxhlet extraction, the practice was best matched to the hypothesis. The ranking of the different bio sludge of the use is based on the hypothesis that Skoghall's use was second best followed by Bäckhammar's use which was the worst in accumulating PHA in the bacterial culture.