BASIN PEAT SORBTION CAPACITY IMPROVEMENT FOR OIL SPILL RESPONSE

BASIN PEAT SORBTION CAPACITY IMPROVEMENT FOR OIL SPILL RESPONSE

Research article

Chukhareva N. V.¹, Blokhina O.L.²

₁Associate professor, candidate of chemical science, National Research Tomsk Polytechnic University, Natural Resources Institute, Oil and gas transport Department

₂Undergraduate student,  National Research Tomsk Polytechnic University, Natural Resources Institute, Oil and gas transport Department

Abstract

This article is concerned with the investigation of basin peat sorption capacity in Tomsk field. Experimental results showed the thermal treatment efficiency of sorbent production for oil spill response.

Key words: natural sorbent, oil capacity, basin peat, oil spill response, thermal treatment.

According to the Federal Subsoil Resources Management Agency [1], the growth of the energy consumption and industrial production as a whole has lead to the inevitably increase in different accidents, oil spills, which in its turn, furthers environmental pollution. Official data indicates the fact that the annual oil loss involves 5 million tons\year [2].

Mechanical and sorption methods are used for spill disposal activities. In case of significant oil spills different mechanical skimmers are applied such as threshold oil-spill boats, centrifugal, auger-type and adhesion skimmers. However, these methods are non-effective if the oil spill film thickness on waters is approximately 1…2 mm. In this case, different sorption materials are used. Nowadays, a number of researchers [3…5] are developing new effective sorbents for oil spill response, involving the following requirements: oil capacity (efficiency), cost, availability, raw material life specification, transportation costs, utilization, environmental safety, etc [6]. Thus, the urgent problem today is to develop and produce cheap, effective and efficient sorbents, based on peat.

Many researchers [7] recommend using poorly decomposed bog peat as raw material, due to its high porosity and extent surface area. However, this restricts the development of a resource base for further production.

The objective of the following research is to investigate the sorbent properties of basin peat in Tomsk region and its further thermal treatment as a significant oil capacity factor.

The gravimetric method (according to requirements: ТU 214-10942238-03-95) was applied in determining the oil capacity G_N (gr. /1 gr. of peat) [6]. For experiments sorbed oil was stock tank oil from ATU of “Centrsibneftprovod” Ltd. (the selected oil mixture is according to Tomsk oil field quality characteristics of GOST 51858-2002). The characteristics of investigated samples are depicted in Table 1.

Peat was preliminary dried into air-dried samples and sieve-grinded to 4mm. The oil capacity of these dried samples G_N^d , which are 2.93 ±2.5 gr.\ 1gr of peat (at  Р = 0,95, number of experiments n ≥ 5)were studied.

 Table 1. Sample characteristics

The investigation [7] showed that the hydrophilic property of peat is connected with its sorbent properties in association to oil or oil products (the lower the index, the higher the peat sorption capacity). Thermal treatment is one of the most effective methods to decrease peat hydrophilic properties and increase its hydrophobic properties. In this research peat thermal treatment is conducted in accordance to the method described in [9], i.e. temperature range up to100 ^oС, 150 ^oС, 200 ^oС, 250 ^oС, within waste gas content media at heating velocity of  5…7 ^o С/min.

The research results of oil capacity G_N of thermal-treated peat can be seen in Table 2. Thermal-treated peat at the temperature range from 100 ^oС to 200 ^oС leads to the increase of oil capacity G_Nfrom 2.98± 2.5% to 3.07 ± 2.5% gr. /1gr. of peat. Further temperature increase results in the reduction of peat sorbent capacity up to 2. 97 gr. / gr. (Tab.2).

Table 2. Thermal treatment temperature impact of  basin (moor) peat on its oil capacity

Peat	Oil code number  ( kg./m3, at 20 ºС)	Temperature, oС	Oil capacity GN, gr. /1gr. of peat
Basin (moor)	А (846)	-	2.93 ± 2.5%
		100	2.98 ± 2.5%
		150	3.01 ± 2.5%
		200	3.07 ± 2.5%
		250	2.97 ± 2.5%

Obtained results [8, 9] can explain the fact that under conditions of high temperatures moisture and resins precipitate   from the peat, changing its porosity. At the same the absence of oxygen (waste gas content media) excludes oxidation of the peat surface, which in its turn, after the removal of those functional compound elements providing hydrophilic properties attains hydrophobic properties. Thermal treatment temperature increase in investigated basin peat   samples results in significant peat chemical structure changes, i.e. peat compaction which decreases its sorbent capacity in relation to stock tank oil.

Conclusion:

1. Oil capacity of basin peat with average decomposition degree (35%) is within the range of 2.93 ±2.5 % gr. /1gr. of peat.
2. Thermal treatment of basin peat of up to 200 ^oС increases the oil capacity from 3.07 ± 2.5% gr. /1gr. of peat.
3. Further temperature increases of basin peat results in the decrease of its sorbent capacity in relation to investigated stock tank oil.

References

1. Federal Subsoil Resources Management Agency / Access mode: http://neoos.ru/pdf/21022012/brushlinskii.pdf.
2. A.N. Nabatkin, V.N. Khlebnikov. Use sorbent materials in oil spill response. 2000. №11.61 pp. (rus)
3. Gridin O., Gridin S., Muratov V., Muratov E., 2003 Method for producing a hydrophobic sorbent. Russian Federation Patent 2214859.
4. Burmistrova T., et al. 2009. Peat properties investigation for environmental solutions. Chemistry of Plant Origin Materials 3, pp. 157-160 (rus)
5. Knatko V., Knatko M., 2003 Sorbent for purification of polluted enviroments. Russian Federation Patent 2209113.
6. Discharges Over a Surface of Liquid Hydrocarbons. Kamenshikov S., Bogomolni E.  2006. Regular and Chaotic Dynamics. 528 pp.
7.  Novoselova L., Sirotkina E. Peat-based sorbents for the purification of contaminated environments. Solid Fuel Chemistry . 2008. №4. 251-256 pp.
8. N. Chukhareva, Maslov S., Dolgikh S. Influence of environment and thermal modification method on element composition and properties of low-moor peat. Chemistry of plant raw material. 2004. №2.  61 –66 pp. (rus)
9. M. Klavins, D. Porshnov. Approaches for peat modification to improve oil sorption capacity / Access mode: http://www.wseas.us/e-library/conferences/2011/Corfu/GEMESED/GEMESED-05.pdf