Ekonomska primerjava različnih tehnologij sušenja lesnih sekancev

diplomsko delo univerzitetnega študijskega programa

Špela Hajduk (Author), Darko Goričanec (Mentor), Danijela Doberšek (Co-mentor)

Abstract

Lesni sekanci so kosi sesekanega lesa, običajno merijo do 10 cm v dolžino, in se uporabljajo za ogrevanje. Vendar, kljub njihovi ugodni ceni in vse nižjim cenam kurilnih naprav z visokim izkoristkom ter avtomatskim delovanjem, v Sloveniji še zmeraj ne prevladujejo kot najbolj pogosto uporabljena biomasa za namene ogrevanja. Sveži lesni sekanci vsebujejo okrog 50 % vlage. Prednost kurilnih naprav za lesne sekance je, da se lahko prilagajajo njihovi kakovosti. Sekanci z vsebnostjo vlage od 20 do 35 % so primerni za večino kotlov, ki obratujejo na lesne sekance, vendar imajo le-ti pri bolj suhem materialu večji izkoristek. Sekanci se lahko posušijo na naravni način, da se skladiščijo in hranijo na suhem ter zračnem prostoru. Drugi način je tehnično sušenje, s katerim se lahko posušijo do zahtevane vlažnosti. Ta način je učinkovitejši, vendar dražji. Sekanci so lahko iz več vrst lesa, od tega je odvisna tudi njihova kurilna vrednost oziroma kakovost. Izdelujejo se s sekanjem okroglega lesa, ali pa se zeleni sekanci sušijo tehnično do zahtevane vlažnosti. Namen diplomskega dela je primerjava različnih tehnologij prisilnega sušenja lesnih sekancev s poudarkom na srednjetemperaturnem sušenju, to je sušenje pri približno 80 °C. Izmed velikega števila ponudnikov sušilnikov na tržišču sta se pri zahtevanih pogojih sušenja za najbolj optimalna izkazala bobenski in tračni sušilnik. Masni pretok lesnih sekancev je bil v obeh primerih enak, prav tako moči sušilnikov. Karakteristični obratovalni in konstrukcijski podatki, na podlagi katerih so se izvedli izračuni porabe energije za sušenje in ekonomska primerjava, so bili pridobljeni od proizvajalcev obeh tipov sušilnikov.

Keywords

OVE;biomasa;lesni sekanci;sušenje;sušilniki;ekonomika;

Data

Language:	Slovenian
Year of publishing:	2014
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[Š. Hajduk]
UDC:	674.815(043.2)
COBISS:	17849878
Views:	2762
Downloads:	358
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	ǂThe ǂeconomical comparison of various technologies for drying wood chips
Secondary abstract:	Wood chips are blocks of chopped wood, usually about 10 cm long and used for heating. Despite their favorable price, increasingly lower prices of combustion plants with high efficiency, and automatic operations, they still do not prevail as the most used biomass for heating in Slovenia. Fresh wood chips contain about 50 % moisture. The advantage of combustion plants for wood chips is that they can adapt to the quality of wood chips. Wood chips that contain 20–35 % of moisture are appropriate for the majority of boilers, but are more efficient with dryer material. Chips can be dried in two different ways. The first is naturally, by storing them in a dry and airy storage room. The second way is technical drying, which can dry wood chips to the required moisture. The technical way of drying wood chips is more efficient, but also more expensive. The wood chips can be made out of several different types of wood and the type of wood has also an effect on their caloric value and quality. They are made by chopping the round wood, or technically drying green wood chops to the necessary moisture. The intention of my bachelor’s thesis is to compare different technologies of coercive drying of wood chips with emphasis on middle-temperature drying (drying at approximately 80 °C). Out of a bigger number of bidders of dryers on the market, we found out, that under the necessary conditions for drying, the drum and belt dryers were the most optimal. The mass flow and the power of dryers were the same in both cases. Characteristic operating and design data, on which the calculations of energy consumption and economic comparison were made, were gained from the producers of both types of dryers.
Secondary keywords:	renewable energy sources;biomass;wood chips;drying;dryers;economics;
URN:	URN:SI:UM:
Type (COBISS):	Undergraduate thesis
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	XX, 146 str.
ID:	8728753