123 resultados para green processes
Resumo:
Ilmastonmuutos, ympäristön saastuminen sekä luonnonvarojen ehtyminen lukeutuvat voimakkaimpiin taustalla vaikuttaviin tekijöihin, joiden vuoksi ympäristönäkökohdat ovat nousseet yhä voimakkaammin esille julkisissa hankinnoissa. Julkisten hankintojen tekijät ovat velvoitettuja huomioimaan talouden ohella myös ympäristönäkökohdat. Suuren ostovolyyminsa vuoksi julkinen sektori voi toimia suunnannäyttäjänä ympäristöä säästävien hankintojen toteuttajana. Tämä Pro gradu –tutkielma kartoittaa ekologisten hankintojen merkitystä suomalaisissa kunnissa vuonna 2016. Tavoitteena on selvittää mitä julkisten hankintojen ekologisuus kunnille merkitsee, miten ekologisuus näkyy hankintaprosessissa sekä mitkä tekijät ovat ekologisten hankintojen esteenä ja mitkä tekijät puolestaan kannustavat kuntia tekemään ekologisia hankintoja. Tutkimuksen tuloksena selvisi, että kunnat suhtautuvat ekologisuuteen hankinnoissa varsin positiivisesti ja ennen kaikkea ympäristönäkökohdat koetaan tärkeänä osana hankintoja. Ympäristönäkökohtien huomioiminen hankintaprosessissa koetaan kuitenkin melko vaikeaksi. Erityisesti tiedon puute, hinta ja taloudelliset resurssit vaikeuttavat ekologisten hankintojen toteutusta. Positiivisesti ympäristönäkökohtien huomioimiseen hankinnoissa puolestaan vaikuttavat henkilöstön osaaminen, taloudellisuus ja lainsäädäntö.
Resumo:
Lipids were extracted from Chlorella algae with supercritical hexane. The high lipids yield of approximately 10% was obtained at optimum conditions of 300 rpm stirring speed and 2 h duration compared to the total contents of lipids being 12%. Furthermore, an easiness of hexane recovery may be considered as economically and ecologically attractive. For the first time, in the current work catalytic hydrodeoxygenation (HDO) of Chlorella algal lipids was studied over 5 wt% Ni/H-Y-80 and 5 wt% Ni/SiO2 at 300 C and under 30 bar total pressure in H2. A comparative HDO of stearic acid was carried out under similar conditions. The conversion of lipids was about 35% over 5 wt% Ni/H-Y-80 after 6h, whereas, 5 wt% Ni/SiO2 was totally deactivated after 60 min. The selectivity to hydrocarbons (C15-C18) is 6%. As a comparison, complete conversion of stearic acid over 5 wt% Ni/H-Y-80 was achieved in 6 h. The transformation of lipids proceeded mostly via hydrogenation and hydrolysis with formation of free fatty acid (FFA). The lower activity might be attributed to deactivation of catalysts caused by chlorophylls and carotenoids. Even though the conversion is low, future studies in HDO of lipids extracted from other algae species having higher lipid content could be proposed. Coke resistant catalyst might be considered to improve catalytic activity.
Resumo:
Today, companies need to mind the environment in all their actions. Policies, regulations and growing pressure from environmentally conscious public are driving corporations to invest increasingly in their green images. Communication plays a key role in forming and maintaining that image. This thesis explores how six selected companies communicate about their environmental efforts and activities, and its linkage to their green images, in annual and sustainability reports and in Facebook. The companies come from the U.S. and Europe and operate in three different industries: ICT, oil and gas, and aerospace & defense. Qualitative and quantitative content analyses are conducted to examine 36 reports and 121 Facebook messages, collected from the period of 2010-2014, and from 2005 for comparison. The results show that although the quality and quantity of environmental disclosure is increasing, there is still room for improvement. Overall, disclosure in the ICT sector is on the highest level. The European companies disclose more and on average have stronger green images than the American ones. Emissions and ways to reduce them is by far the most covered topic in both continents and in all three industry sectors. The messages in Facebook are closer to advertising, and overall the platform is utilized surprisingly little.