1. Introduction:

This report explains the organic waste management practices along with current statistics of waste generation in Lahore. Lahore is the capital of province Punjab and second largest city of Pakistan. Report primarily focuses on the organic waste management in the city. Composting and generation of Biogas are the major practices, which are being followed worldwide to manage organic waste. Efforts are also being made in the city Lahore by private, public and public-private partnership to manage organic waste of the city.

2. Background and Justification:

There are various factors that determines the solid waste generation of the area like, population, major activities/practices of the peoples, atmospheric and weather and living style of population. But most contributing factor is the population of the area. Estimated current population of Lahore is about 10million and current solid waste generation rate is 0.65Kg/person/day. With reference to the total population and solid waste generation rate, total amount waste being generated on daily basis can be calculated as:

Solid Waste Generation per day =
                        = Solid Waste Generation Rate * Total Population
= 0.65Kg/person/day * 10000000person
= 6500000 Kg/day
= 6500 Tonnes/day   

According to ISTAC, Waste Characterization Report 2011, 72.76% of waste which being generated in Lahore is organic waste.

Approximately 4729.4 tonnes of organic waste is being generated in the city. So it is highly important to set composting and biogas facilities in the city to manage the organic waste effectively.

3. Organic Waste Management Lahore:

In 2008 an effort had been made by Saif Goup of Companies in partnership with local government and a composting facility was settled in the city with name of Lahore Compost. Initially facility was operated on trial basis where 300 tonnes of waste were started processing on daily basis after successful operation of trail period an agreement had been made with the local government for 25 years and now the facility is being operating, at the rate of 1000tonnes of waste per day.

4. Organic Waste Processing at Composting Plant:

Composting process which is being adopted at Lahore Compost is Windrow Composting. Working of plant has been divided into various steps that start from the arrival of waste and ends at the packing of end product. These steps are described below.

4.1 Waste Arrival

Lahore Compost Ltd (LCL) receives waste materials of neighboring settlements namely Data Town, Gullberg, Aziz Bahatti Town, Ravi and Wagha towns Waste from the these part of the Lahore unloaded here by the trucks of City Dist. Govt. Lahore and Lahore Waste Management Company. Daily unloading of waste is ranging from 1000 tons to 1200 tons. Major component of waste reached at the site is Organic matter specially the waste arising from the vegetable markets and from the field crops. Waste of animal manure and the waste from vegetable markets are directly placed into the compost piles for the composting. The trucks which are suspected to contain the waste material that has organic matter less than 40 percent are discarded and directly move to the Mahmood Booti dumping area.

Monitoring of waste received by LCL is to be carried out in order to find out the composition of waste received. This monitoring helps to find out the quantity of the end product and also helps to find out the efficiency of the composting activities. Monitoring of the waste is carried out at monthly basis, in the monitoring process 200 trucks are selected and from each truck 10kg waste is taken by composite sampling. Sorting of this sample waste is carried out in order to find the percentage composition of each component of waste. 

4.2 Weighing Station

Weighing is an obvious and necessary step for composting because the efficiency of the process can be evaluated according to the waste received. For the weighing purpose every truck has been assigned a truck code for example LBC 5442 and weight of truck arriving at the site being saved in the software against this code. A worker sitting in the weighing room just note the weight of loaded truck and put it into the software formula it automatically calculate the weight of Waste loaded into the truck. (by subtracting the weight of empty truck from the weight of loaded truck)

4.3 Sorting

Separation of inorganic and non-biodegradable material from the waste is necessary before the start of composting. In this regards stones, metals, glass, rags and plastic must be separated before the composting. Segregation waste is being done by two ways:

4.3 (a) Manual Sorting

The most common and simple method for the separation of material from MSW is hand-sorting. Company workers are assigned a duty of separation of stones, glass, and plastic from the waste that is moving on the sort line. They take position along a conveyor belt, either on one or both sides. They are provided with the gloves and face mask. Workers collect the in-organic waste moving in the conveyors. The conveyor, a system to transfer wastes from one location to another (commonly used for manual and mechanical removal of individual components from the waste stream), is the most common unit.

4.3 (b) Magnetic Separation:

Separation of metal from the organic waste is necessary before the waste being ready for the composting. Separation of metals at the Lahore compost is done by magnetic separator. Magnetic separation is a relatively simple unit process designed to recovery of magnetic material, primarily ferrous metals, from mixed Municipal Solid waste (MSW).

Although the magnetic separators have been used for numerous industrial application, their use with MSW present some problems. There is tendency for non-magnetic material such as plastic and paper to entrap with the ferrous metal thereby reducing the purity of the recovered metal product. Furthermore, sharp edges of metal shorten the life of rubber belts. Although the resale value of scrap is low.

4.4 Size Reduction:

Size reduction of the solid waste which is being prepared for the composting is an essential step for composting. Small size of the waste material provides more space to microbes to attack also easily to be in handling and packaging. Reduction of the size of waste is also important because it provides more oxygen to the each component of the waste and reduced the time of composting. After the successfully separation of inorganic material from the waste bulk, the waste is then move in conveyor toward the size reduction chamber. The size reduction chamber consists of a huge Screening Drum (screening drum MTR 1850 ) which rotates and reduces the size of waste up to several mili-meter according to the sieve size. The reduction chamber also separates the shopping bags and other plastic bags from the waste moving on the conveyors belts.

From, one end the waste is entering to the chamber and the other end it throws out the plastic bags present in the waste. While the waste, which size is being reduced come out from the bottom of the drum.

4.5   Windrow Formation

Windrow means a long heap of regular shape and cross section. Windrows of rectangular shapes formed and waste is being left to process. Moisture, PH and aeration kept control and maintained to accelerate the composting process. Aeration is done mechanically by using mechanical turner. Once the organic waste fully degraded into compost its color turns to brown to dark brown. Prepared compost removed from the poles or windrows and again subjected into the screening unit for final size reduction and for the separation of inert as well.

4.5   Packing  

Finally prepared compost packed into the bags and sent market for sale. Major amount of compost, are being used by Parks and Horticulture Authority Lahore to build publics parks and public sites.

Although the efforts made to manage organic waste of the city is appreciable but still around 3500 tons of organic waste is still being dumped at dump site. So more efforts are need to made to manage organic waste and also to reduce load on landfill/dump site.

Farhan Ahmad
TUNZA Eco generation Ambassador to Pakistan